31 The Andro- meda Galaxy spiral galaxy (type Sb) M31 is the famous Andromeda galaxy, our nearest large neighbor galaxy, forming the Local Group of galaxies together with its companions (including M32 and M110, two bright dwarf elliptical galaxies), our Milky Way and its companions, M33, and others. Visible to the naked eye even under moderate conditions, this object was known as the “little cloud” to the Persian astronomer Abd-al-Rahman Al-Sufi, who described and depicted it in 964 AD in his Book of Fixed Stars: It must have been observed by and commonly known to Persian astronomers at Isfahan as early as 905 AD, or earlier. R.H. Allen (1899/1963) reports that it was also appeared on a Dutch starmap of 1500. Charles Messier, who cataloged it on August 3, 1764, was obviously unaware of this early reports, and ascribed its discovery to Simon Marius, who was the first to give a telescopic description in 1612, but (according to R.H. Allen) didn’t claim its discovery. Unaware of both Al Sufi’s and Marius’ discovery, Giovanni Batista Hodierna independently rediscovered this object before 1654. Edmond Halley, however, in his 1716 treat of “Nebulae”, accounts the discovery of this “nebula” to the French astronomer Bullialdus (Ismail Bouillaud), who observed it in 1661; but Bullialdus mentions that it had been seen 150 years earlier (in the early 1500s) by some anonymous astronomer (R.H. Allen, 1899/1963). It was longly believed that the “Great Andromeda Nebula” was one of the nearest nebulae. William Herschel believed, wrongly of course, that its distance would “not exceed 2000 times the distance of Sirius” (17,000 light years); nevertheless, he viewed it at the nearest “island universe” like our Milky Way which he assumed to be a disk of 850 times the distance of Sirius in diameter, and of a thickness of 155 times that distance.
32 Satellite galaxy of M31 elliptical galaxy (type E2)Hubble Space Telescope’s exquisite resolution has allowed astronomers to resolve, for the first time, hot blue stars deep inside an elliptical galaxy. The swarm of nearly 8, 000 blue stars resembles a blizzard of snowflakes near the core (lower right) of the neighboring galaxy M 32, located 2.5 million light-years away in the constellation Andromeda. Discovered 1749 by Guillaume Joseph Hyacinthe Jean Baptiste Le Gentil de la Galaziere (Le Gentil). M32 is the small yet bright companion of the Great Andromeda Galaxy, M31, and as such a member of the Local Group of galaxies. It can be easily found when observing the Andromeda Galaxy, as it is situated 22 arc minutes exactly south of M31’s central region, overlaid over the outskirts of the spiral arms. It appears as a remarkably bright round patch, slightly elongated at position angle 150-330 deg, and is easily visible in small telescopes. Its ellipticity is about E2, i.e. the smaller diameter, or axis, or its elliptically shaped image, projected along our line of sight, is about a fraction of 0.2, or 20 percent, shorter than its larger axis. M32 is an elliptical dwarf of only about 3 billion solar masses, and a linear diameter of some 8,000 light years, very small compared to its giant spiral-shaped neighbor. Nevertheless and surprising for such a small galaxy, its nucleus is of comparable properties as that of M31: About 100 million solar masses, 5000 suns per cubic parsecs, are in rapid motion around a central supermassive object. Because of this nucleus, M32 is sometimes classified as cE2 instead of simply E2, e.g. by NED. Near the center of this galaxy, the sky would be dominated by this object, and full with the members of this galaxy, while at the edges, only one hemisphere would be filled with them, the other showing only few outlying stars and the intergalactic space. Toward M31, this galaxy would give a fascinating view in the night sky of a virtual astronomer in the outskirts of M32. M32 appears to us superimposed over the spiral arms of greater M31. Therefore, it is of interest if it lies before or behind the great galaxy’s disk. Spectroscopic investigations have not shown any absorption which would be expected if its light had passed the interstellar matter in M31’s disk, which suggests that M32 is closer to us than that portion of M31. The radial velocity of M32 has been measured at 203 km/s (R. Brent Tully) or 205 +/- 8 km/s (NED) in approach in the heliocentric system, i.e., toward our Solar System; corrected for galactic rotation, M32 is currently about at rest (RV=0) w.r.t. the Milky Way’s Galactic Center. Compared to M31, it is approaching about 100 km/s slower, and considering its closer distance, it is apporaching M31 at this velocity in the radial component. M32 and the other bright companion of M31, M110, are the closest bright elliptical galaxies to us, therefore also the among best investigated. They were both first resolved into stars by Walter Baade in 1944 with the 100-inch Hooker telescope on Mt. Wilson when he also resolved the nucleus of M31 (Baade 1944). Baade recognized that their stars were mostly old population II stars, and about as bright (and thus at roughly the same distance) as M31, thus confirming their proximity to the large spiral galaxy. There are remarkable differences between these dwarf galaxies: While M32 is a typical generic elliptical, compact and of high surface brightness, M110 is much more loose, of lower surface brightness, and exposes peculiar structures; now, M110 is often classified as a dwarf spheroidal galaxy instead of elliptical. Remarkably, M32 has no globular clusters (again, in difference to M110 which has 8 ) .
110 Satellite galaxy of M31 elliptical galaxy (type E6pec), The last object in the Messier catalog is an elliptical galaxy in the constellation of Andromeda. It is the second brighter of the two satellite galaxies of M31, the Andromeda galaxy. All three of these galaxies are members of the local group. M110 was discovered by Messier in 1783 when he discovered M31, but it was not included in his catalog at the time. It is located about 2.9 million light years from Earth. At magnitude 8.5, it can easily be found with binoculars. It is an impressive sight in a 4-inch or larger telescope.
2 is a globular cluster of stars, located in the constellation of Aquarius. This cluster is located about 50,000 light years from Earth. It is believed to be about 175 light years in diameter. M2 is one of the brightest and largest globular clusters in the sky. This cluster’s visual magnitude of 6.5 means it can easily be found with a pair of binoculars. A telescope will be required to resolve the cluster’s individual stars.
72 globular cluster, In the constellation Aquarius lies a globular cluster known as M72. This object is one of the more remote globular clusters in the Messier catalog. It has a diameter of about 90 light years, and is located over 53,000 light years from Earth. Although its apparent magnitude is only 9.3, this cluster’s extreme distance means that it is one of the brightest globulars yet discovered. Visually, it is a somewhat loose cluster. M72 is approaching us at over 250 km/sec. This object may be difficult to locate with binoculars but makes an easy target with a telescope.
73 system or asterism of 4 stars, Another interesting object to be found in Aquarius is M73. This object is unlike most of Messier’s other discoveries. M73 is a small cluster of four stars. It is officially classified as an asterism. An asterism is a star pattern, and is different from a constellation. For example, the big dipper is an asterism within the constellation of Ursa Major. M73 may appear as a nebula at first glance with small instruments. Some astronomers believe this object to be a true star cluster, but there is little evidence at this time to support that claim. M73 is easily visible in binoculars, but it takes a telescope to resolve the individual stars in the formation.
36 open cluster,, Nestled within the constellation Auriga is M36, a galactic cluster of about 60 stars. This cluster is around 4,100 light years from Earth and has a diameter of about 14 light years. At an age of only 25 million years, it is quite young and contains no red giant stars. M36 has a visual magnitude of 6.3 with the individual member stars ranging in magnitude from 9 to 14. This relatively large cluster is easy to spot with binoculars. In telescopes, it is best viewed at low powers.
37 open cluster, M37 is a galactic cluster of about 150 stars located in the constellation Auriga. It has a diameter of about 4,600 light years, making it roughly twice the size as nearby M36. At a distance of around 4,600 light years, it is the richest and brightest of the Auriga clusters. It is also the oldest at about 300 million years. M37 is considered to be one of the finest open clusters in the heavens. It is easily viewed in binoculars and small telescopes.
38 open cluster, M38 is the third of the three Auriga clusters. It is about 4,200 light years away and has a linear diameter of around 21 light years. The cluster has a total visual magnitude of 7.4 and contains more than 100 stars. The brightest stars of the cluster have been said to form a Greek letter Pi, or according to some, an oblique cross. M38 is of intermediate age at about 220 million years. It is a large cluster and is easily viewed with binoculars. In telescopes, it is best viewed at low power.
44 Praesepe, the Beehive Cluster open cluster, Located in the constellation of Cancer is an impressive galactic cluster of stars known as M44. This famous cluster is also known as Praesepe, and more recently, the Beehive Cluster. The Beehive was given this name because to some it resembles a swarm of bees. It is one of the few deep-sky objects visible to the naked eye and has been known since ancient times. M44 consists of about 350 stars, 40 of which are bright enough to be seen in a small telescope. This cluster is about 577 light years from Earth and is believed to be approximately 400 million years old.
67 open cluster, The constellation of Cancer is the site of an open star cluster called M67. It is one of the oldest known open clusters and is believed to be over 3 billion years old. It is also the oldest cluster in the Messier catalog. This cluster is located about 2,700 light years from Earth. It contains around 500 stars, some 200 of which are believed to be white dwarfs. At magnitude 6.1, it is an easy target for the binocular observer. Viewing through a telescope will reveal some of the cluster’s fainter stars.
3 globular cluster, Located in the constellation Canes Venatici, M3 is a tight cluster of almost 500,000 stars. This cluster is located approximately 30,000 light years from Earth. It contains about 170 faint variable stars, which is more than any other globular cluster. A visual magnitude of 6.2 makes this bright cluster an easy target for binoculars and telescopes alike.
51 The Whirlpool Galaxy spiral galaxy. The graceful, winding arms of the majestic spiral galaxy M51 (NGC 5194) appear like a grand spiral staircase sweeping through space. They are actually long lanes of stars and gas laced with dust. This sharpest-ever image, taken in January 2005 with the Advanced Camera for Surveys aboard the NASA/ESA Hubble Space Telescope, illustrates a spiral galaxy’s grand design, from its curving spiral arms, where young stars reside, to its yellowish central core, a home of older stars. The galaxy is nicknamed the Whirlpool because of its swirling structure. The Whirlpool’s most striking feature is its two curving arms, a hallmark of so-called grand-design spiral galaxies. Many spiral galaxies possess numerous, loosely shaped arms that make their spiral structure less pronounced. These arms serve an important purpose in spiral galaxies. They are star-formation factories, compressing hydrogen gas and creating clusters of new stars. In the Whirlpool, the assembly line begins with the dark clouds of gas on the inner edge, then moves to bright pink star-forming regions, and ends with the brilliant blue star clusters along the outer edge. Some astronomers believe that the Whirlpool’s arms are so prominent because of the effects of a close encounter with NGC 5195, the small, yellowish galaxy at the outermost tip of one of the Whirlpool’s arms. At first glance, the compact galaxy appears to be tugging on the arm. Hubble’s clear view, however, shows that NGC 5195 is passing behind the Whirlpool. The small galaxy has been gliding past the Whirlpool for hundreds of millions of years. As NGC 5195 drifts by, its gravitational muscle pumps up waves within the Whirlpool’s pancake-shaped disk. The waves are like ripples in a pond generated when a rock is thrown in the water. When the waves pass through orbiting gas clouds within the disk, they squeeze the gaseous material along each arm’s inner edge. The dark dusty material looks like gathering storm clouds. These dense clouds collapse, creating a wake of star birth, as seen in the bright pink star-forming regions. The largest stars eventually sweep away the dusty cocoons with a torrent of radiation, hurricane-like stellar winds, and shock waves from supernova blasts. Bright blue star clusters emerge from the mayhem, illuminating the Whirlpool’s arms like city streetlights. The Whirlpool is one of astronomy’s galactic darlings. Located 31 million light-years away in the constellation Canes Venatici (the Hunting Dogs), the Whirlpool’s beautiful face-on view and closeness to Earth allow astronomers to study a classic spiral galaxy’s structure and star-forming processes.
63 Sunflower galaxy spiral galaxy, Located within in the constellation of Canes Venaciti is M63, a spiral galaxy also known as the Sunflower Galaxy. It earned this name due to its sunflower-like appearance. It was originally discovered in 1779 by Messier’s friend, Pierre Mechain. This galaxy is located about 37 million light years from Earth, and is part of a group of galaxies that includes M51. A good telescope and optimal sky conditions will reveal the galaxy’s spiral arms as a grainy background that brightens considerably towards its center. Color photos of this galaxy show star-forming regions throughout its spiral arms.
94 spiral galaxy, In the constellation of Leo, the lion, can be found an interesting spiral galaxy known as M94. This galaxy has an extremely bright inner region, surrounded by a ring of active star-forming regions. Color photographs of the galaxy reveals the blue colors of these young stars. Another region of moderate star formation is also visible. The distance of this galaxy is not well known, but best estimates place it at about 15 million light years from us. With a magnitude of 8.2, it can be found with binoculars. Telescopes will reveal much more detail in this galaxy.
106 spiral galaxy, Canes Venatici is the home of spiral galaxy known as M106. It is located about 25 million light years from Earth and is receding from us at the rate of 537 km/sec. This galaxy is rotated to our line of sight, which gives is an elongated appearance. In color photographs, the spiral arms end in bright blue knots. These are believed to be young star clusters composed of giant, hot blue stars. M106 can be spotted in binoculars but requires a small telescope to reveal any details.
41 open cluster Cpricornus, M41 is an open, or galactic, cluster located within the constellation of Canis Major. This cluster is located about 4 degrees South of Sirius, the brightest star in the night sky. M41 contains about 100 stars of varying colors. Several of these stars are red giants, the brightest of which is about 700 times brighter than the Sun. This cluster is about 26 light years across and is situated approximately 2,300 light years from Earth. M41’s age is estimated at about 190 million years. It is easily visible with a pair of binoculars.
30 globular cluster, Located in the constellation Capricornus, M30 is a globular cluster of stars located about 25,000 light years from Earth. This dense cluster is around 75 light years in diameter and contains 12 known variable stars. It is actually approaching us at a speed of 164 kilometers per second. M30’s large size and dense structure make it a remarkable object when viewed through binoculars or small telescopes.
52 open cluster, M52 is an open cluster of stars situated within the constellation of Cassiopeia. It can be seen against the backdrop of a Milky Way field. This object has been described as a “salt and pepper” cluster due to its dense arrangement of about 200 bright stars. M52 is believed to be only 23 million years old. Its distance from Earth is not certain. Estimates range anywhere from 3,000 to 7,000 light years. With a magnitude of 7.3, this cluster is easily visible to an observer with binoculars. A small telescope will reveal the cluster’s fainter stars.
103 open cluster,M 103 is one of the latest additions to the Messier catalog. It was discovered by Pierre Mechain and included in the catalog before Messier had a chance to observe it directly. It was also the last object to be included in the first publication of Messier’s catalog. This is an open cluster of stars situated in the constellation of Cassiopeia. It consists of about 40 stars located some 8,000 light years from Earth. Visually, M103 is said to form an arrowhead shape. This bright cluster is an easy target for a pair of binoculars. A small telescope will be able to resolve the cluster’s fainter stars.
77 spiral galaxy, The constellation Cetus is the location of a beautiful spiral galaxy known as M77. This is one of the largest galaxies in the Messier catalog. The brightest parts of this galaxy measure about 120,000 light years in diameter, but its fainter extensions bring it out to a total of 170,000 light years. This galaxy is believed to be located around 60 million light years from Earth and is receding from us at a whopping 1100 km/sec. Visually, it appears as a large spiral with broad structured arms. At a magnitude of 8.9, it can easily be located with a pair of binoculars on a good night. large telescopes will reveal some of the more intricate details in this galaxy.
53 globular cluster, Discovered 1775 by Johann Elert Bode. Globular star cluster M53 is one of the more outlying globulars, being about 60,000 light years away from the Galactic center, and almost the same distance (about 58,000 light years) from out Solar system. At this distance, its apparent angular diameter of 13′ corresponds to a linear diameter of roughly 220 light years. It is rapidly approaching us at a velocity given by Mallas as 112 km/s, by Harris as 79 km/s. M53 has a bright compact central nucleus of about 2′ in diameter, although its stars are not very concentrated toward the center when compared to other globulars, and a gradually decreasing density profile to the outer edges. Harlow Shapley classified it in density, or concentration class V. While the NGC, following John Herschel, suspected its brightest red giant stars at about 12th magnitude, the Deep Sky Field Guide lists them at 13.8 mag, and the hirizontal branch at about magnitude 16.9. The cluster’s overall spectral type is givan as F6. Its discoverer Johann Elert Bode, who found it on February 3, 1775, described it as a “rather vivid and round” nebula. Charles Messier, who independently rediscovered and cataloged it two years later, on February 26, 1777, found it “round and conspicuous” and that it resembles M79. William Herschel was the first to resolve it into stars, and found it similar to M10. As in all globular clusters, the stars of M53 are apparently “metal-poor”, which means that they contain only little quantities of elements heavier than helium (actually mainly elements like carbon and oxygene); those of M53 are even below the average globular cluster members in “metallicity”. It contains the considerably respectable number of 47 known RR Lyrae variables, some of them were reported to have changed their periods irreversibly with time (Kenneth Glyn-Jones). In small amateur telescopes, M53 appears as a slightly oval nebulous object with a large, bright center, of rather even surface brightness and evenly fading out to the edges. Mallas reports that he saw many stars in the 4-inch refractor under excellent viewing conditions, with the central part appearing somewhat grainy. In somewhat larger telescopes, its outer fringes appear resolved into stars, while the central part is still unresolved and grainy, with one star standing out, in telescopes of about 8-inch aperture. Large instruments of about 12-inch up show it well resolved, with a moderately concenterated nucleus and stars spread out to about 12 arc minutes diameter. M53 can be easily found just 1 deg NE of the 4th-mag star, 42 Alpha Comae Berenices, a visual binary star (A: 5.05, B: 5.08, both of spectral type F5V). Alpha Comae itself may be located by either following the line from Arcturus via Eta Bootis by a further 11 deg to the W, or by following the line of Gamma – Delta – Epsilon Virginis by another 7 deg NNE. At only about 1 degree separation to the east, the faint and quite loose globular cluster NGC 5053 comes into the field of view, which is at roughly the same distance as M53 (53,500 light years), indicating that these clusters are also physically rather close together. NGC 5053 contains significantly less stars than M53, in particular doesn’t have such a densely populated, compact bright center, so that its classification as globular was doubted in the past (now it was confirmed by spectroscopy).
64 Blackeye galaxy spiral galaxy A collision of two galaxies has left a merged star system with an unusual appearance as well as bizarre internal motions. Messier 64 (M64) has a spectacular dark band of absorbing dust in front of the galaxy’s bright nucleus, giving rise to its nicknames of the “Black Eye” or “Evil Eye” galaxy. Fine details of the dark band are revealed in this image of the central portion of M64 obtained with the Hubble Space Telescope. M64 is well known among amateur astronomers because of its appearance in small telescopes. It was first cataloged in the 18th century by the French astronomer Messier. Located in the northern constellation Coma Berenices, M64 resides roughly 17 million light-years from Earth. Discovered 1779 by Edward Pigott. M64 is the famous Black Eye galaxy, sometimes also called the “Sleeping Beauty galaxy”. The conspicuous dark structure is a prominent dust feature obscuring the stars behind. This feature also enables one to determine, or at least estimate, which of the galaxy’s sides is nearer and which more remote; in case of M64, it seems that the southern side is nearer to us. J.D. Wray, in his Color Atlas of Galaxies, points out that M64 may be taken as prototype for a class of galaxies called “ESWAG”, for Evolved Second Wave (star forming) Activity Galaxy. As becomes evident in color photos, the main spiral pattern is consisted of an intermediate aged stellar population. Stellar formation has first evolved outside following the density gradient, forming stars as long as there was sufficient interstellar matter available, and then dying out slowly. As the matter was flowing back from the evolved stars, by stellar wind, supernovae, and planetary nebula activity, more and more interstellar matter could accumulate again, so that finally there was enough matter to start the formation of new young stars again. This second wave of star formation has apparently reached now the region where the dark dust lane appears. The dust feature is well visible even in smaller telescopes. M64 was recently shown to have two counterrotating systems of stars and gas in its disk: The inner part of about 3,000 light years radius is rubbing along the inner edge of the outer disk, which rotates opposite and extends up to at least 40,000 light years, at about 300 km/sec. This rubbing process is probably the reason for the observed vigorous star formation process, which is currently under way, and can be observed as the blue knots imbedded in the peculiar dust lane on one side of the nucleus. It is speculated that this peculiar disk and dust lane may be caused by material from a former companion which has been accreted but has yet to settle into the mean orbital plane of the disk.
85 elliptical galaxy, Coma Berenices is the home of M85, a lenticular galaxy that is part of the Virgo cluster of galaxies. It is very similar in appearance and brightness to M84. It was the site of a supernova in 1960 that reached a magnitude of 11.7. This galaxy is located some 60 million light years from Earth and is believed to have a diameter of around 125,000 light years. It appears to be composed almost entirely of old yellow stars and is receding from us at about 700 km/sec. As with M84, this galaxy is a disappointing sight in anything but a large telescope.
88 spiral galaxy, One of the brighter members of the Virgo cluster is the spiral galaxy, M88. Located about 60 million light years from Earth, this galaxy is inclined approximately 30 degrees to our line of sight. This gives it an elongated visual appearance which resembles that of the Andromeda Galaxy, M31. M88 is believed to be nearly 130,000 light years in diameter and is receding away from us at about 2000 km.sec. This is one of the more rewarding galaxies in the Virgo cluster for observers using small instruments. A large telescope will bring out some of the more subtle details.
91 spiral galaxy, Located in the constellation of Coma Berenices is a small, dim galaxy known as M91. Until recently, this galaxy had been missing. Messier’s notes had given the wrong position for this object. An amateur astronomer from Texas finally figured out its true location in 1969. This galaxy is classified as a barred spiral. The center part of the galaxy displays a prominent bar-shape, which can be seen even in small telescopes. M91 is a member of the Virgo cluster of galaxies and it located about 60 million light years from Earth. It is receding from us at a rate of 400 km/sec. With a magnitude of only 10.2 it is best observed with a large telescope.
98 spiral galaxy, M98 is a small, dim galaxy located in the constellation of Coma Berenices. It is a member of the Virgo cluster of galaxies, which contains a total of 16 galaxies from the Messier catalog. It is one of the most difficult galaxies in the cluster to observe. Some astronomers believe that this could actually be a foreground object and not actually a member of the cluster, but there is no compelling evidence to support this claim. It is located about 60 million light years from Earth and is approaching us at a rate of 1200 km/sec. M98 is a spiral galaxy situated nearly edge-on to our line of sight. This gives it an extremely elongated shape. It is best viewed with a large telescope.
99 spiral galaxy, Another Virgo cluster member in Coma Berenices is a spiral galaxy known as M99. It is unusual in appearance in that its shape is very asymmetric. It is believed that this asymmetric shape is the result of a recent encounter of another member of the Virgo cluster. It is located about 60 million light years from Earth and is receding from us at an unusually high rate of 2324 km/sec. Three supernovae have been observed in this galaxy. One was seen in 1967 while two other occurred in 1972 and 1986. With a magnitude of only 9.9, this galaxy may be a difficult find for the binocular observer. Large telescopes will provide the best views.
100 spiral galaxy, M100 is one of the brightest members of the Virgo cluster of galaxies. It is located in the constellation of Coma Berenices and is a beautiful example of a nearly face-on spiral galaxy. Visually, this galaxy has two bright spiral arms and several fainter arms. Color photographs reveal the young blue stars in these spiral arms. The galaxy has a slightly asymmetric shape which may be the result of interaction with neighboring galaxies. M100 can be located with a pair of binoculars, although the best detail can be seen with a large telescope.
29 open cluster, M29 is a small, coarse group of stars in the constellation Cygnus. It is located about 7,000 light years from Earth. The cluster contains only six stars with a magnitude brighter than 9.5 which form a small, stubby dipper in the center. This is not a very impressive object when viewed in binoculars or small telescopes. Larger instruments will be needed to resolve the fainter stars in the cluster.
39 open cluster, Located in the constellation Cygnus, M39 is a very loose cluster of about 30 stars. It lies only 800 light years from Earth, which makes it one of the closest open clusters in the sky. The cluster has a diameter of about 7 light years, and is believed to be over 250 million years old. With a visual magnitude of 5.2, it is a bright cluster although very loosely populated. This cluster is an easy target for binoculars and is best observed in telescopes at low power.
102 is the last of the “missing” Messier objects. There is some uncertainty as to whether the galaxy pictured here is M102. Due to an 18th century error, M101 may have been misclassified as M102. It is widely believed that M102 may be a lenticular galaxy located in the constellation Draco. It is a is a dim object with a visual magnitude of only 9.9 and can be hard to find without dark skies and ideal observing conditions.
35 open cluster, Located in the constellation Gemini, M35 is a galactic cluster of around 200 stars. This cluster is 2,800 light years from us and has a diameter of about 24 light years. It is believed to be around 110 million years old, which makes it an intermediate-aged cluster. With an apparent diameter about the same as the full moon, M35 can easily be seen with the naked eye near the 3 “foot stars” of the constellation Gemini. It is best viewed with low-powered optical instruments.
13 Great Hercules Globular Cluster globular cluster, Also known as the Hercules cluster, M13 is perhaps the finest and most well-known globular cluster in the Northern hemisphere. It originally was discovered by Edmond Halley in 1714. Halley noted that the cluster could easily be seen with the naked eye on dark, moonless nights. As its common name would imply, M13 lies in the constellation Hercules. It is about 25,000 light years from us, and has an impressive diameter of about 150 light years.
92 globular cluster, The constellation of Hercules is the site of a globular cluster known as M92. This cluster is located about 26,000 light years from Earth and has a diameter of around 85 light years. It is believed to be around 16 billion years old and is approaching us at a rate of 112 km/sec. This is an outstanding object, and with a magnitude of 6.4, it can actually be seen with the naked eye on a dark night. It is a prime candidate for observing with binoculars. A telescope will be able to resolve the individual stars in the cluster.
48 open cluster, Located in the constellation of Hydra, M48 is an open cluster of about 80 stars. 50 of these are brighter than magnitude 13 and are easily visible in binoculars and small telescopes. The cluster is easily visible to the naked eye under ideal observing conditions. M48 is about 23 light years in diameter and is located some 1,500 light years from Earth. Its age is estimated at about 300 million years.
68 globular cluster, The constellation Hydra contains a globular cluster of stars known as M68. This cluster is around 140 light years in diameter and is located about 40,000 light years from Earth. This is a relatively small cluster that may be difficult to locate with binoculars. It is an easy target for any telescope 4-inches or larger.
83 spiral galaxy, In the constellation Hydra can be found a spectacular face-on spiral galaxy. This is M83, the Southern Pinwheel Galaxy. It earned its name from the distinct pinwheel shape of its long spiral arms. Color photographs of this galaxy reveal a wide range of colors from the yellow central core of old stars to the blue spiral arms of young stars. Several red knots can also be seen These are gaseous nebulae where active star formation is taking place. Dark lanes of dust are also visible throughout the galaxy’s disk. M83 is situated about 15 million light years from Earth. It is receding from us at around 337 km/sec. This galaxy has been the site of six supernovae, which is more than any other Messier galaxy. It was also the first galaxy to be discovered beyond the local group.
65 spiral galaxy, Located in the constellation of Leo is a small triplet of galaxies. One of its members is M65. This is a spiral galaxy located about 35 million light years from us. It has an obvious elliptical shape, due to the fact that we are viewing it from an angle. The galaxy’s magnitude of 9.3 may make it a bit challenging to find with binoculars, but it is an easy target for the telescope. As is the rule with most galaxies, bigger is definitely better. The light gathering power of a large telescope will reveal much more detail in the galaxy’s disk.
66 spiral galaxy, Another member of this triplet of galaxies in Leo is a spiral galaxy known as M66. This galaxy is much larger than its close neighbor, M65. Its visual appearance is a bit unusual in that its spiral is irregular in shape. The galaxy’s spirals are believed to have been deformed by close encounters with its neighbors. M66 islocated about 35 million light years from Earth. Its magnitude of 8.9 makes it a little easier to observe with binoculars. A good telescope and dark skies will reveal some of the detail in this glaxy.
95 spiral galaxy, Leo is also the constellation in which the spiral galaxy, M95, can be found. It is a member of a small group of galaxies known as the M96 group. This is a barred spiral galaxy with a visual magnitude of 9.7. It is located about 38 million light years from Earth. Visually, it shows a definite bar-shaped center with nearly circular spiral arms. Because of this, it has also been referred to as a ringed galaxy. This is not a very bright object, and may be a difficult target for binoculars. Telescopes will provide the best viewing.
96 spiral galaxy, Yet another galaxy to be seen in the constellation of Leo is M96. It is the brightest member of the M96 group of galaxies, with a visual magnitude of 9.2. This object is located about 38 million light years from Earth and has a diameter of around 100,000 light years. Visually it has a bright inner disk composed of old yellow stars surrounded by blue knots of young stars. It is inclined about 35 degrees to our line of sight, which gives it a slightly elongated appearance. Although it can be spotted with binoculars on a good night, a telescope is required to see any real detail in this galaxy.
105 elliptical galaxy, M105 is the brightest member of a group of galaxies in the constellation of Leo known as the M96 group. It is an elliptical galaxy located about 38 million light years from Earth. This object was discovered by Pierre Mechain in 1781. It was found 3 days earlier than M101 but was not included in the original publication of Messier’s catalog. With a visual magnitude of only 9.3, this galaxy is best observed in a 4-inch or larger telescope.
79 globular cluster, The constellation Lepus is the site of a beautiful globular cluster known as M79. This cluster is unusual because of its location in the sky. Most globular clusters are grouped near the center of our galaxy. This one is much closer to us. It is only only 40,000 light years from Earth but 60,000 light years from the galactic center. It is believed to have a diameter of around 100 light years. It has a slightly elliptical shape and is receding from us at about 200km/sec. At magnitude 7.7, it is a bright object and should be relatively easy to spot in binoculars. A telescope is required to resolve the individual stars in the cluster.
56 globular cluster, In the constellation Lyra can be found a small, dim globular cluster known as M56. This cluster lacks the bright core that is visible in many other globulars. It is believed to have a diameter of only 60 light years, and is located about 45,000 light years from Earth. It is actually approaching us at a speed of about 145 km/sec. Due to its small size and magnitude of only 8.3, M56 is not a great object for the binocular astronomer. Telescopes larger than 10 inches can resolve the cluster quite nicely.
57 The Ring Nebula planetary nebula, The NASA/ESA Hubble Space Telescope has captured the sharpest view yet of the most famous of all planetary nebulae: the Ring Nebula (M57). In this October 1998 image, the telescope has looked down a barrel of gas cast off by a dying star thousands of years ago. This photo reveals elongated dark clumps of material embedded in the gas at the edge of the nebula; the dying central star floating in a blue haze of hot gas. The nebula is about a light-year in diameter and is located some 2, 000 light-years from Earth in the direction of the constellation Lyra. Discovered by Antoine Darquier de Pellepoix in 1779. The famous ring nebula M57 is often regarded as the prototype of a planetary nebula, and a showpiece in the northern hemisphere summer sky. Recent research has confirmed that it is, most probably, actually a ring (torus) of bright light-emitting material surrounding its central star, and not a spherical (or ellipsoidal) shell, thus coinciding with an early assumption by John Herschel. Viewed from this equatorial plane, it would thus more resemble the Dumbbell Nebula M27 or the Little Dumbbell Nebula M76 than its appearance we know from here: We happen to view it from near one pole. This is contrary to the belief expressed e.g. in Kenneth Glyn Jones’ book. There are even indications from investigations of deep observations such as George Jacoby’s deep photos obtained at Kitt Peak National Observatory that the overall shape might be more that of a cylinder viewed along the direction of the axis than that of a ring, i.e., we are looking down a tunnel of gas ejected by a star at the end of its nuclear-burning life. Eventually, these observations have given evidence that the equatorial ring or cylinder has lobe-shaped extensions in polar directions, similar to those found in deep images of M76, but even more resembling other planetaries like NGC 6302, see e.g. the review by Sun Kwok (2000). The deep observations also show an extended halo of material extending off to over 3.5 arc minutes (Hynes gives 216 arc seconds, quoting Moreno & Lopez, 1987), remainders of the star’s earlier stellar winds. The halo was discovered in 1935 by J.C. Duncan (Duncan, 1935).
50 open cluster, Located in the constellation of Monoceros is an open cluster of stars known as M50. This cluster is estimated to contain about 200 stars. It is about 10 light years in diameter and is believed to be located around 3,000 light years from Earth. The appearance of this cluster has been described as a heart-shape. With a magnitude of 6.3, M50 is easily visible with a pair of binoculars. Telescopes will reveal more of the fainter members of the group.
9 is a globular cluster of stars, located within the constellation of Ophiuchus. It is located at the edge of a dark patch of dark nebulosity. This cluster is about 26,000 light years from us and has a diameter of about 70 light years. The central region of the cluster has a distinct oval shape. M9’s visual magnitude of 7.7 make it a bit more challenging to find than some of the other globular clusters. It can be found with binoculars, and can be quite impressive in a 4-inch telescope.
10 globular cluster, Globular cluster M10 lies in the constellation of Ophiuchus. This is a very bright cluster with a central region that appears slightly pear-shaped. It is about 70 light years in diameter and lies about 16,000 light years from Earth. With a visual magnitude of 6.6 and an apparent diameter of 15 arc minutes, this is one of the best clusters to be viewed with both binoculars and small telescopes.
M12 globular cluster, Globular cluster M12, in the constellation Ophiuchus, is nearly a twin of M10. It is just a bit fainter and only slightly larger. Like its twin, it does not contain a lot of variable stars. M12 lies at a distance of 18,000 light years from Earth and has a diameter of about 75 light years. Visually it is a fairly remarkable sight. Its visual magnitude of 6.7 makes it an easy target to find with binoculars, and a telescope will bring out its slightly irregular shape.
14 globular cluster, Located in the constellation Ophiuchus, globular cluster M14 has a slightly elliptical shape to it. This cluster is noticeably smaller than M10 and M12, but it contains a large number of variable stars, over 70 in all. This cluster has a diameter of about 55 light years and lies about 23,000 light years from Earth. It was the sight of a nova in 1938. With a magnitude of 7.6, it be located with binoculars, although a telescope is required to show any detail in the cluster.
19 globular cluster, Globular cluster M19 can be found in the constellation Ophiuchus. It is situated about 20,000 light years from Earth and has a diameter of about 30 light years. M19 lies very close to the galactic center, only 4,600 light years from it in fact. This is a relatively bright globular cluster, and is easily identifiable with binoculars. A telescope will reveal the fact that the cluster has an elliptical shape to it.
62 globular cluster,The constellation Opheiuchus is home to an unusual globular cluster known as M62. This cluster is known for its highly irregular shape. This deformation is believed to be caused by gravitational tidal forces acting on the cluster due to its close proximity to the galactic center. It is only 6,100 light years from the center of our galaxy. The cluster is located about 21,000 light years from Earth. At magnitude 6.5, this is a bright object that can easily be found with a par of binoculars. As with most globular clusters, a small telescope will bring out its glittery details.
107 globular cluster, In the constellation Ophiuchus lies a globular cluster of stars known as M107. It was discovered by Messier’s colleague, Pierre Mechain, in 1782 and was not included in the original publication of the catalog. It is located about 20,000 light years from Earth and is believed to have a diameter of around 60 light years. This cluster is approaching us at a rate of about 147 km/sec. It can be easily found with binoculars and is an impressive sight in a 4-inch telescope at medium magnification.
42 in the Center of the Orion Nebula (the Great Orion Nebula diffuse nebula). This spectacular color panorama of the center the Orion nebula is one of the largest pictures ever assembled from individual images taken with the Hubble Space Telescope. The picture, seamlessly composited from a mosaic of 15 separate fields, covers an area of sky about five percent the area covered by the full Moon. Discovered 1610 by Nicholas-Claude Fabri de Peiresc. Located at a distance of about 1,600 (or perhaps 1,500) light years, the Orion Nebula is the brightest diffuse nebula in the sky, visible to the naked eye, and rewarding in telescopes of every size, from the smallest glasses to the greatest Earth-bound observatories and the Hubble Space Telescope. It is the main part of a much larger cloud of gas and dust which extends over 10 degrees well over half the constellation Orion. The linear extend of this giant cloud is well several hundreds of light years. It can be visualized by long exposure photos (see e.g. Burnham) and contains, besides the Orion nebula near its center, the following objects, often famous on their own: Barnard’s Loop, the Horsehead Nebula region (also containing NGC 2024 = Orion B), and the reflection nebulae around M78. Already impressive in deep visible light photographs, the Orion Cloud is particularly gorgeous in the infrared light. The Orion Nebula itself is still a big object in the sky, extending some 66×60 arc minutes, thus covering four times the area of the full Moon. This corresponds to a linear diameter of about 30 light years. It is also one of the brightest Deep Sky objects, well visible to the naked eye, so that the present author is wondering that its nebulous nature was apparently not documented before 1610, when Nicholas-Claude Fabri de Peiresc (1580-1637), a French lawyer, turned his telescope to this region of the sky (although Ptolemy, as well as later Tycho Brahe and Johann Bayer had cataloged the brightest stars within it as one bright star – the latter cataloging it as Theta Orionis, and Galileo had detected a number of faint stars when first looking at this region with his telescope earlier in 1610). It was independently rediscovered in 1611 by the Jesuit astronomer Johann Baptist Cysatus (1588-1657) of Lucerne who compared it with a comet he had observed in the same year. The first known drawing of the Orion nebula was created by Giovanni Batista Hodierna. All these discoveries apparently got lost for some time, so that eventually Christian Huygens was longly credited for his independent rediscovery in 1656, e.g. by Charles Messier when he added it to his catalog on March 4, 1769.
43 part of the Orion Nebula (de Mairan’s Nebula) diffuse nebula, This is one of the nearest regions of very recent star formation (300, 000 years ago). The nebula is a giant gas cloud illuminated by the brightest of the young hot stars at the top of the picture. Many of the fainter young stars are surrounded by disks of dust and gas that are slightly more than twice the diameter of the Solar System. Discovered before 1731 by Jean-Jacques Dortous de Mairan. M43 is actually a part of the Great Orion Nebula, M42, which is separated from the main nebula by an impressive, turbulent dark lane. It was first reported by de Mairan in 1731 as a “brilliance surrounding a star” which he thought was “very similar to the atmosphere of our Sun, if it were dense enough and extensive enough to be visible in telescopes at a similar distance.” Charles Messier included in his fine drawing of the Orion Nebula, and assigned it an extra catalog number, M43, on March 4, 1769. Moreover, William Herschel took it into his list with the number H III.1, although normally he careful avoided to assign his numbers to Messier objects. In his 1811 paper, Herschel states to have observed it as early as March 4, 1774, and cataloged it
on November 3, 1783. The diffuse nebula M43 surrounds the irregular young “nebula variable” NU Orionis (HD 37061, attn: “N” “U” Orionis, not “Nu Orionis”, i.e. the variable star 2-letter designation, not the Greek letter) of magnitude 6.5-7.6 and spectral type B IV. It seems that M43 is excited to shine by this star, and contains its own, separate small cluster of stars which have formed in this part of the Orion nebula. The dark features along its eastern border are well visible in telescopes starting at about 8 inch. The nebula itself is a fine view even in a 4-inch. Alister Ling in his recent review of observing the Orion nebula with filters (Astronomy, December 1995 issue), mentions the Comma shape of this nebula.
78 diffuse nebula, In the constellation of Orion can be found the brightest diffuse reflection nebula in the sky. This is M78. It is a member of the Orion complex which is a large cloud of dust ad gas near the Orion Nebula, M42. It is the brightest part of a large dust cloud which includes several other small nebulae. This bright nebula is about 1,600 light years from Earth and measures nearly 4 light years in diameter. It shines with the reflected light of several bright blue stars. Visually, this nebula resembles a faint comet. It can easily be seen with just about any size telescope.
15, A Dying Star in Globular Cluster M15 The globular cluster M15 is shown in this color image obtained with the Hubble telescope. Lying some 40, 000 light-years from Earth in the constellation Pegasus, M15 is one of nearly 150 known globular clusters that form a vast halo surrounding our Milky Way galaxy. Each of these spherically shaped clusters contains hundreds of thousands of ancient stars. The stars in M15 and other globular clusters are estimated to be about 12 billion years old. They were among the first generations of stars to form in the Milky Way. This mosaic of the globular cluster M15 (fifteenth object in the Messier catalog of star clusters and nebulae) contains over 30, 000 stars. The Hubble Space Telescope probed the core of M15, the most tightly packed cluster of stars in our galaxy, to look for evidence of either a massive black hole or another remarkable phenomenon: a ‘core collapse’ driven by the intense gravitational pull of so many stars in such a small volume of space. Discovered by Jean-Dominique Maraldi in 1746. Globular cluster M15 is among the more conspicuous of these great stellar swarms. At a distance of about 33,600 light years, its diameter of 18.0 arc min corresponds to a linear extension of about 175 light years, and its total visual brightness of 6.2 magnitudes corresponds to an absolute magnitude of -9.17, or roughly 360,000 times that of our sun. Its brightest stars are about of apparent magnitude 12.6 or absolute magnitude -2.8 or a luminosity of 1,000 times that of our Sun, and its horizontal branch giants are about of magnitude 15.6. Its overall spectral type has been determined as F3 or F4. The globular cluster is approaching us at 107 km/sec. In amateur instruments, M15 appears somewhat smaller, perhaps about 7 arc minutes visually and 12.3 arc minutes photographically. On the other hand, the tidal radius of this globular cluster, beyond which member stars would escape because of the Milky Way galaxy’s tidal forces is a bit larger: 21.5 arc minutes, corresponding to a distance of 210 light years from the cluster’s center. This globular cluster has the third rank in known variable star population, after M3 and Omega Centauri; a total of 112 variables have been identified. One of them is apparently a Cepheid of Type II (a W Virginis star). M15 is perhaps the densest of all (globular) star clusters in our Milky Way galaxy. The Hubble Space Telescope has photographically resolved its superdense core, as shown in this HST image. M15’s core has undergone a process of contraction called “core collapse”, which is common in the dynamical evolution of globulars; of the 150 known globular cluster within our Milky Way Galaxy according to W.E. Harris’ database, 21 have been found to contain a collapsed core (among them, besides M15, the Messier globulars M30 and M70), and there are 8 more candidates, among them M62. This central core is extremely small compared to the cluster, only about 0.14 arc minutes (8,4 arc seconds) in angular diameter, corresponding to a linear extent of roughly 1.4 light years. The half-mass radius is 1.06 arc min, or linearly about 10 light years – half the mass of this cluster is concentrated in the innermost sphere of that radius. It is still unclear if the central core of M15 is packed so dense simply because of the mutual gravitational interaction of the stars it is made of, or if it houses a dense, supermassive object, which would be resembling the supermassive objects in galactic nuclei. The one in M15 would among the nearest and better observable to us, being only little more remote than the Galactic Center and much less obscured by interstellar matter. Although the true nature of these objects remains obscure for the moment, many scientists believe they are strong candidates for “Black Holes”.
34 open cluster, M34 is an open cluster of about 100 stars located in the constellation Perseus. The cluster lies about 1,400 light years from Earth and is believed to be about 190 million years old. The brightest star in the group has a visual magnitude of 7.9, which makes it a bright and easy target for viewing. M34 is visible to the naked eye, and its apparent diameter is nearly that of the full moon. Binoculars and small telescopes with a wide field of view are recommended for this object.
76 The Little Dumbell, Cork, or Butterfly planetary nebula, Located in the constellation of Perseus is a faint planetary nebula known as M76. This nebula is also known as the Little Dumbbell Nebula. Other names that have been given to this object include Cork Nebula, Butterfly Nebula, and Barbell Nebula. At magnitude 10.1 it is one of the fainter of the Messier objects. The appearance of this nebula is very similar to that of M27, the Dumbbell Nebula. As with most planetary nebulae, its distance it not very well known. Best estimates put it at between 1,700 and 15,000 light years from Earth. It takes a good telescope to be able to see any amount of detail on this object.
74 spiral galaxy, In the constellation of Pisces can be found a fine example of a face-on spiral galaxy. This is M74. It is a beautiful spiral around 95,000 light years in diameter. It is located about 35 million light years from Earth. It is moving away from us at nearly 800 km/sec. Color photographs of this galaxy reveal that its spiral arms are littered with clusters of young, blue stars. It is believed to be very similar in size and shape to our own Milky Way galaxy. With a magnitude of 9.4 is may be a challenging object to locate in binoculars. Larger telescopes will reveal the best amount of detail.
46 open cluster, Located in the constellation Puppis, M46 is an open cluster of about 500 stars. About 150 of these have a magnitude of between 10 and 13. This cluster is believed to be around 300 million years old. It is 30 light years across and is located approximately 5,400 light years from the Earth. A large telescope will reveal a small planetary nebula within the cluster. This nebula is not a member of M46 but is actually located between us and the cluster. This object is easily visible in a pair of binoculars with good observing conditions.
93 open ncluster, M93 is an open cluster of stars located within the Puppis constellation. This is a small but bright cluster with a visual magnitude of 6. Its visual appearance has been said to resemble that of a butterfly. Some have even identified it with a starfish. The cluster contains about 80 stars scattered over a distance of around 25 light years. The brightest of these stars are blue giants. M93 is believed to be located some 3,600 light years from Earth. Its can easily be seen with a pair of binoculars. A small telescope will reveal more of the clusters fainter stars.
71 globular cluster, Located in the constellation of Sagitta is a globular cluster known as M71. This is an extremely loose cluster, and for some time there was doubt as to whether this was a globular cluster at all. Some astronomers believed it to be a condensed open cluster. This globular is located about 11,700 light years from Earth and has a diameter of only 25 light years. This makes it one of the smallest known globular clusters. Recent findings suggest that the size may actually be 90 light years, but it is uncertain at this point how many of the surrounding stars are actually part of the cluster. At magnitude 8.2 it can be seen through binoculars on a good night.
8 The Lagoon Nebula diffuse nebula, Known more commonly as the Lagoon nebula, M8 is a beautiful cloud of gas illuminated by a 5.9 magnitude star inside. The nebula is about 150 light years in diameter and lies about 5,200 light years from Earth. M8 is a stellar nursery where many new stars are being formed from the great clouds of gas. With a visual magnitude of 6, this nebula can be easily seen in the constellation of Sagittarius with the naked eye on a dark, clear night. A telescope will reveal some of the more complex patterns of bright and dark areas within the nebula.
17 The Omega or Swan or Horseshoe Nebula diffuse nebula. A watercolour fantasyland? No. It’s actually a photograph of the centre of the Swan Nebula, or M17, a hotbed of newly born stars wrapped in colourful blankets of glowing gas and cradled in an enormous cold, dark hydrogen cloud. This stunning picture was taken by the newly installed Advanced Camera for Surveys (ACS) aboard the NASA/ESA Hubble Space Telescope. The region of the nebula shown in this picture is about 3500 times wider than our Solar System. The area also represents about 60 percent of the total view captured by ACS. The nebula resides 5500 light-years away in the constellation Sagittarius. Like its famous cousin in Orion, the Swan Nebula is illuminated by ultraviolet radiation from young, massive stars – each about six times hotter and 30 times more massive than the Sun – located just beyond the upper right corner of the image. The powerful radiation from these stars evaporates and erodes the dense cloud of cold gas within which the stars formed. The blistered walls of the hollow cloud shine primarily in the blue, green, and red light emitted by excited atoms of hydrogen, nitrogen, oxygen, and sulphur. Particularly striking is the rose-like feature, seen to the right of centre, which glows in the red light emitted by hydrogen and sulphur. As the infant stars evaporate the surrounding cloud, they expose dense pockets of gas that may contain developing stars. Because these dense pockets are more resistant to the withering radiation than the surrounding cloud, they appear as sculptures in the walls of the cloud or as isolated islands in a sea of glowing gas. One isolated pocket is seen at the centre of the brightest region of the nebula and is about 10 times larger than our Solar System. Other dense pockets of gas have formed the remarkable feature jutting inward from the left edge of the image, which resembles the famous Horsehead Nebula in Orion. The ACS made this observation on 1 and 2 April 2002. The colour image is constructed from four separate images taken in these filters: blue, near infrared, hydrogen alpha, and doubly ionised oxygen.
18 open cluster, M18 is a small open cluster of about 20 stars located in the constellation Sagittarius. It lies about 5,000 light years away with a diameter of about 17 light years. The cluster contains only 12 fairly bright stars, and the cluster is rather loose in appearance. It is not one of the best examples of a galactic cluster, but it is a pretty sight in a small telescope. This a fairly young cluster, containing bright blue as well as yellow and orange stars.
20 The Trifid Nebula diffuse nebula, This NASA/ESA Hubble Space Telescope image of the Trifid Nebula reveals a stellar nursery being torn apart by radiation from a nearby, massive star. The picture also provides a peek at embryonic stars forming within an ill-fated cloud of dust and gas, which is destined to be eaten away by the glare from the massive neighbor. This stellar activity is a beautiful example of how the life cycles of stars like our Sun is intimately connected with their more powerful siblings. Discovered by Charles Messier in 1764. Charles Messier discovered this object on June 5, 1764, and described it as a cluster of stars of 8th to 9th magnitude, enveloped in nebulosity. The Trifid Nebula M20 is famous for its three-lobed appearance. This may have caused William Herschel, who normally carefully avoided to number Messier’s objects in his catalog, to assign four different numbers to parts of this nebula: H IV.41 (cataloged May 26, 1786) and H V.10, H V.11, H V.12 (dated July 12, 1784). That he numbered this object at all may have its reason in the fact that Messier merely described it as `Cluster of Stars’. The name `Trifid’ was first used by John Herschel to describe this nebula. The dark nebula which is the reason for the Trifid’s appearance was cataloged by Barnard as Barnard 85 (B 85). The red emission nebula with its young star cluster near its center is surrounded by a blue reflection nebula which is particularly conspicuous to the northern end. The nebula’s distance is rather uncertain, with values between 2,200 light years (Mallas/Kreimer; Glyn Jones has 2,300) and about 7,600 light years (C.R. O’Dell 1963). The Sky Catalog 2000 gives 5,200 light years, the WEBDA database has 3140, the Hubble Press Release of Jeff Hester (STScI-PRC99-42) gives “about 9000” light years. As often for nebulae, magnitude estimates spread widely: Kenneth Glyn Jones gives 9.0, while Machholz has estimated 6.8 mag. This may partly come from the fact that the exciting star, ADS 10991, is a triple system of 7th integrated magnitude (with components A: 7.6, B: 10.7, C: 8.7 mag). All are extremely hot; component A is of spectral type O5 or O6. The presence of this considerably bright triplet makes brightness estimates for the nebula difficult. In the sky, the Trifid nebula M20 is situated roughly 2 degrees northwest of the larger Lagoon Nebula M8, so that both nebulae form a nice target for wide field photographs, as these images of the M8 and M20 region, or the big DSSM image of this region. It is even closer to the open cluster M21 and shows up in the upper left edge of the M21 image.
21 open cluster, Located in the constellation Sagittarius, M21 is an open cluster of about 40 stars varying in magnitude from 9 to 12. The cluster is located about 3,000 light years from Earth and has a diameter of about 10 light years. M21 has a total visual magnitude of about 6.5, which makes it an impressive sight in any small telescope. It can also be easily located with binoculars just a short distance from M20, the Trifid Nebula.
22 globular cluster, Hint of planet-sized drifters bewilders Hubble scientists (WFPC2 view) This image shows the globular cluster M22 as seen with the NASA/ESA Hubble Space Telescopes workhorse instrument, the Wide Field and Planetary Camera 2. A team of American and European astronomers has studied the cluster in search for traces of short-lived brightening, due to an effect called microlensing, of faint stars in the background (too faint to be seen in this representation). Seven microlensing events were seen one normal event where a dwarf star in M22 passed in front of a background star, and six short events strongly suggesting the existence of free-floating planet-sized objects in M22. If confirmed these planets would be the smallest detected which are not orbiting any star. M22, also known as NGC 6656, is the brightest globular cluster visible from the Northern hemisphere and it is an easy naked eye object. The 12 to 14 billion year old cluster is about 8, 500 light years distant and about 65 light years across. Its angular diameter is 24 arc minutes or almost the size of the full Moon. This Hubble view measures about 3 light years across.
23 open cluster, M23 is a loose galactic cluster of stars found in the constellation Sagittarius. This cluster lies about 2,150 light years from Earth and contains about 150 stars of magnitude 10 and fainter. It stretches over a distance of about 20 light years in diameter and has a total visual magnitude of 6.9. M23 can easily be resolved with binoculars and its large size makes it a prime candidate for small, wide-field telescopes.
24 Milky Way Patch star cloud with open cluster (NGC 6603), Located in Sagittarius, M24 is not really a true deep sky object. It is actually a cloudy patch of stars in the Milky Way. The area is framed by dark patches of dust, which gives it the impression of being a separate object. M24 has a total visual magnitude of 4.6, which makes it easily visible to the unaided eye. A good telescope will reveal a small galactic cluster known as NGC 6603 hiding in the center of M24.
25 open cluster, M25 is a relatively compressed galactic cluster found in the constellation Sagittarius. It contains about 86 stars, one of which is a known cepheid variable. This cluster is located about 2,000 light years from Earth and has a diameter of around 23 light years. The 6.5 visual magnitude of M25 makes it easy to find with binoculars, but a small telescope will be able to reveal the many colors of its member stars.
M28 globular cluster, Located in the constellation Sagittarius, M28 is a tight globular cluster of several thousand stars. It lies about 19,000 light years from Earth and has a diameter of around 75 light years. This cluster’s visual magnitude of 6.8 makes it a fine site in any optical instrument. A small telescope will reveal the cluster’s slight oval shape. Some have even said it somewhat resembles a cucumber.
54 globular cluster, Located in the constellation of Sagittarius is a globular cluster known as M54. It is one of the brighter globular clusters in the sky. This object’s close proximity to Zeta Sagittarii, the southernmost star in the constellation, makes it very easy to find. Although this cluster is bright, it is small. It could be mistaken for a star in binoculars. A telescope is really the best way to view this fine object. M54 is estimated to be about 60,000 light years from Earth. Some controversy has recently surfaced about this cluster. Some astronomers believe that it may not be a part of our galaxy at all, but of a newly discovered dwarf galaxy. If this turns out to be true, its distance from Earth could be as much as 80,000 light years. It would also be the first extragalactic globular cluster to ever be discovered.
55 globular cluster, Another fine globular cluster to be found in Sagittarius if M55. This is a large cluster with a somewhat loose arrangement of stars. Its apparent size is about 2/3 that of the full moon. It has a diameter of about 110 light years, and is believed to be located only 20,000 light years from Earth. This would make it among the closest of the globular clusters. M55 has been described as very grainy in appearance, due to its loose structure. Its size and brightness make it easy to identify in binoculars. Through a small telescope, its grainy structure will be more apparent.
69 globular cluster, Sagittarius is a constellation that literally swarms with interesting deep-sky objects. One of these is a globular cluster known as M69. It is one of the smaller and fainter globular clusters in the Messier catalog. In fact, Messier originally missed this object when he looked for it in 1764 but later found it with a better telescope in 1780. This cluster is believed to be about 55 light years in diameter and is located some 27,000 light years from Earth. It can just barely be seen on a dark night with a pair of 7×50 or 10×50 binoculars as long the observer is not too far north.
70 globular cluster, A close neighbor to M69 in Sagittarius is the globular cluster M70. This cluster is nearly identical to its neighbor in size and brightness, although it is just a bit larger. It is also somewhat more distant, located about 28,000 light years from Earth. It is believed to be around 65 light years in diameter. Like M69, this cluster is also very low in the southern sky and is difficult to observe from northern locations. It is rapidly receeding from us at a speed of about 200 km/sec. M70 became somewhat famous in 1995 when the comet Hale-Bopp was discovered near it by two astronomers who were observing the cluster. With a magnitude of 7.9, it makes a good candidate for binocular observing.
75 globular cluster, The galactic hunting grounds of Sagittarius is the home of yet another globular cluster known as M75. At a distance of 60,000 light years, it is one of the the most remote globular clusters in the Messier catalog. It is believed to be around 100 light years in diameter. It is a very compact and concentrated cluster. Because of its small size, larger telescopes are required to resolve it into individual stars. A pair of binoculars on a good night should be able to find it as a small, fuzzy blob.
4, globular cluster, that lies in the constellation of Scorpius. It is located about 7,000 light years from the Earth. This makes M4 one of the closest of the globular clusters. It is also one of the most open, or loose globular clusters. M4 is receding from us at a rate of 65 km/sec. With a visual magnitude of 5.6, this cluster can easily be seen with the naked eye on a dark, clear night. With the aid of a small telescope, it displays a central band of bright stars in a linear formation.
6 The Butterfly Cluster open cluster, M6 is a galactic, or open cluster of stars found in the constellation of Scorpius. It has a diameter of about 20 light years and lies about 2,000 light years from Earth. This cluster is composed mainly of blue and white stars with the brightest being a yellow or orange giant. The shape of this cluster somewhat resembles that of a butterfly, giving rise to its more common name, the butterfly cluster. At magnitude 5.3 it is an easy find with binoculars.
7 Ptolemy’s Cluster open cluster, Another galactic cluster to be found in the rich hunting grounds of the constellation of Scorpius is M7, also known as Ptolemy’s cluster. It is a large group of about 80 stars set against the background of fainter and more distant Milky Way stars. M7 is about 18 light years in diameter and lies about 800 light years from us. The brightest star of the cluster is a yellow giant with a magnitude of 5.6. This bright cluster makes a sine target for the binocular observer.
80 globular cluster (NGC 6093) This stellar swarm is M80 (NGC 6093), one of the densest of the 147 known globular star clusters in the Milky Way galaxy. Located about 28, 000 light-years from Earth, M80 contains hundreds of thousands of stars, all held together by their mutual gravitational attraction. Globular clusters are particularly useful for studying stellar evolution, since all of the stars in the cluster have the same age (about 15 billion years), but cover a range of stellar masses. Every star visible in this image is either more highly evolved than, or in a few rare cases more massive than, our own Sun. Especially obvious are the bright red giants, which are stars similar to the Sun in mass that are nearing the ends of their lives. Discovered 1781 by Charles Messier. M80 is a fine 8th mag globular. Its 10′ angular diameter corresponds to roughly 95 light years linear dimension at its distance of 32,600 light years. Its appearance resembles very much that of a faint comet without tail. This dense stellar swarm contains several 100,000s of stars, held together by their mutual gravitational attraction. It is one of the densest globulars in our Milky Way Galaxy. As was found by astronomers from observations with the Hubble Space Telescope in 1999 in the visible and UV part of the electromagnetic spectrum, M80 contains a large number of so-called “Blue Stragglers” in its core, about twice as much as any other globular investigated with the HST. These stars are blue and bright stars which appear near the main-sequence of the Hertzsprung-Russell diagramm, and thus appear more massive and younger than the globular clusters age. The reason is very probably that these stars lost their cooler envelopes in close encounters with other stars. Their large number in M80 indicates an exceptionally high stellar collision rate in the core of this globular cluster. Globular cluster M80 was one of the original discoveries of Charles Messier, who found it on January 4, 1781, and cataloged it as a “Nebula without a star, .. resembling the nucleus of a comet.” William Herschel was the first to resolve it (before 1785), and found it was “one of the richest and most compressed clusters of small stars I remember to have seen.” On May 21, 1860, a nove occurred in M80, completely changing the appearance of this globular cluster for some days. This nova, also designated T Scorpii was discovered by Auwers at Berlin, had mag 7.0 on May 21 and 22, and faded to mag 10.5 on June 16. It was independently seen by Pogson. It was reported that Pogson had seen a rebrightening in early 1864, but this appears improbable, as nobody else could confirm this notion. The maximum brighteness of this nova corresponds to an absolute magnitude of about -8.5, if it was a cluster member. At its maximum, the nova was considerably brighter than the whole cluster !
11 The Wild Duck Cluster open cluster, Located in the constellation Scutum, M11 has been described as one of the richest and most compact open clusters. This cluster lies 6,000 light years from Earth and has a diameter of about 21 light years. It is composed of more than 2,900 stars, 600 of which have a visual magnitude brighter than 15. To some, the shape of the cluster resembles that of a flock of flying ducks. This has helped it to earn the name, Wild Duck Cluster. This is an easy target to locate with a pair of binoculars.
26 open cluster, Located in the constellation Scutum, M26 is a small galactic cluster of about 90 stars. It can be found only 3 1/2 degrees from its cousin, M11, but is not nearly as impressive. This cluster lies about 5,000 light years from us and has a diameter of around 22 light years. Its visual magnitude of 8 makes it less bright than most of the other galactic clusters. This cluster can easily be seen with binoculars, but a 4-inch refractor telescope will only resolve more of its fainter stars.
5 globular cluster, Located in the constellation Serpens, globular cluster M5 is one of the few to show an elliptical shape. It is believed to be one of the oldest of the globular clusters, at an age of about 13 billion years. M5 is located about 23,000 light years from Earth, and has a diameter of about 130 light years. This cluster’s visual magnitude of 5.6 males it easy to spot on a clear night with dark skies with a pair of binoculars. A telescope will resolve the cluster’s individual stars.
16 open cluster associated with the Eagle Nebula (IC 4703) Appearing like a winged fairy-tale creature poised on a pedestal, this object is actually a billowing tower of cold gas and dust rising from a stellar nursery called the Eagle Nebula. The soaring tower is 9.5 light-years or about 90 trillion kilometres high, about twice the distance from our Sun to the next nearest star. Stars in the Eagle Nebula are born in clouds of cold hydrogen gas that reside in chaotic neighbourhoods, where energy from young stars sculpts fantasy-like landscapes in the gas. The tower may be a giant incubator for those newborn stars. A torrent of ultraviolet light from a band of massive, hot, young stars [off the top of the image] is eroding the pillar. The starlight also is responsible for illuminating the tower’s rough surface. Ghostly streamers of gas can be seen boiling off this surface, creating the haze around the structure and highlighting its three-dimensional shape. The column is silhouetted against the background glow of more distant gas. The edge of the dark hydrogen cloud at the top of the tower is resisting erosion, in a manner similar to that of brush among a field of prairie grass that is being swept up by fire. The fire quickly burns the grass but slows down when it encounters the dense brush. In this celestial case, thick clouds of hydrogen gas and dust have survived longer than their surroundings in the face of a blast of ultraviolet light from the hot, young stars. Inside the gaseous tower, stars may be forming. Some of those stars may have been created by dense gas collapsing under gravity. Other stars may be forming due to pressure from gas that has been heated by the neighbouring hot stars. The first wave of stars may have started forming before the massive star cluster began venting its scorching light. The star birth may have begun when denser regions of cold gas within the tower started collapsing under their own weight to make stars. The bumps and fingers of material in the centre of the tower are examples of these stellar birthing areas. These regions may look small but they are roughly the size of our solar system. The fledgling stars continued to grow as they fed off the surrounding gas cloud. They abruptly stopped growing when light from the star cluster uncovered their gaseous cradles, separating them from their gas supply. Ironically, the young cluster’s intense starlight may be inducing star formation in some regions of the tower. Examples can be seen in the large, glowing clumps and finger-shaped protrusions at the top of the structure. The stars may be heating the gas at the top of the tower and creating a shock front, as seen by the bright rim of material tracing the edge of the nebula at top, left. As the heated gas expands, it acts like a battering ram, pushing against the darker cold gas. The intense pressure compresses the gas, making it easier for stars to form. This scenario may continue as the shock front moves slowly down the tower. The dominant colours in the image were produced by gas energized by the star cluster’s powerful ultraviolet light. The blue colour at the top is from glowing oxygen. The red colon in the lower region is from glowing hydrogen. The Eagle Nebula image was taken in November 2004 with the Advanced Camera for Surveys aboard the NASA/ESA Hubble Space Telescope.
1 The Crab Nebula supernova remnant.In the year 1054 A.D., Chinese astronomers were startled by the appearance of a new star, so bright that it was visible in broad daylight for several weeks. Today, the Crab Nebula is visible at the site of that bright star. Discovered 1731 by British amateur astronomer John Bevis. The Crab Nebula is the most famous and conspicuous known supernova remnant, an cloud of gas created in the explosion of a star as supernova. The supernova was noted on July 4, 1054 A.D. by Chinese astronomers, and was about four times brighter than Venus, or about mag -6. According to the records, it was visible in daylight for 23 days, and 653 days to the naked eye in the night sky. It was probably also recorded by Anasazi Indian artists (in present-day Arizona and New Mexico), as findings in Navaho Canyon and White Mesa (both AZ) as well as in the Chaco Canyon National Park (NM) indicate; there’s a review of the research on the Chaco Canyon Anasazi art online. In addition, Ralph R. Robbins of the University of Texas has found Mimbres Indian art from New Mexico, possibly depicting the supernova. The Supernova 1054 was also assigned the variable star designation CM Tauri. It is one of few historically observed supernovae in our Milky Way Galaxy. The nebulous remnant was discovered by John Bevis in 1731, who added it to his sky atlas, Uranographia Britannica. Charles Messier independently found it on August 28, 1758, when he was looking for comet Halley on its first predicted return, and first thought it was a comet. Of course, he soon recognized that it had no apparent proper motion, and cataloged it on September 12, 1758. It was the discovery of this object which caused Charles Messier to begin with the compilation of his catalog. It was also the discovery of this object, which closely resembled a comet (1758 De la Nux, C/1758 K1) in his small refracting telescope, which brought him to the idea to search for comets with telescopes (see his note). Messier acknowledged the prior, original discovery by Bevis when he learned of it in a letter of June 10, 1771. Although Messier’s catalog was primarily compiled for preventing confusion of these objects with comets, M1 was again confused with comet Halley on the occasion of that comet’s second predicted return in 1835. This nebula was christened the “Crab Nebula” on the ground of a drawing made by Lord Rosse about 1844. Of the early observers, Messier, Bode and William Herschel correctly remarked that this nebula is not resolvable into stars, but William Herschel thought that it was a stellar system which should be resolvable by larger telescopes. John Herschel and Lord Rosse, erroneously, thought it is “barely resolvable” into stars. They and others, including Lassell in the 1850s, apparently mistook filamentary structures as indication for resolvability.
45 Subaru, the Pleiades the Seven Sisters open cluster, M45 is an object that has been known since the earliest times. Most commonly known as the Pleiades, it is a galactic cluster of about 500 young stars located within the constellation of Taurus. This cluster has also been named the Seven Sisters, after its seven brightest stars. These stars can easily be seen with the naked eye. The Pleiades are believed to be very young – only 100 million years old. They are located only 380 light years from Earth. Photographs of the cluster reveal traces of the nebula out of which the stars originally formed. Binoculars will show much more than the seven brightest stars, and a large telescope will show reveal some of the nebulous material surrounding the stars.
33 The Triangulum Galaxy (also Pinwheel) spiral galaxy. This is a Hubble Space Telescope image (right) of a vast nebula called NGC 604, which lies in the neighboring spiral galaxy M33, located 2.7 million light-years away in the constellation Triangulum. Probably discovered by Hodierna before 1654. Independently discovered by Charles Messier 1764. The Triangulum galaxy M33 is another prominent member of the Local Group of galaxies. This galaxy is small compared to its big apparent neighbor, the Andromeda galaxy M31, and to our Milky Way galaxy, but by this more of average size for spiral galaxies in the universe. One of the small Local Group member galaxies, LGS 3, is possibly a satellite of M33, which itself may be a remote but gravitationally bound companion of the Andromeda galaxy M31. M33 is approaching us (our Solar System) at 182 km/s according to R. Brent Tully, or at 179 +/-3 km/s according to NED. Corrected for our motion around the Milky Way’s Galactic Center, it is approaching our Galaxy at 24 km/sec. M33 was probably first found by Hodierna before 1654 (perhaps together with open cluster NGC 752). It was independently rediscovered by Charles Messier, and cataloged by him on August 25, 1764. Nevertheless, William Herschel, who otherwise carefully avoided to number Messier’s objects in his survey, assigned it the number H V.17, on the ground of an observation dated September 11, 1784. Also because of the cataloging of Herschel, the brightest and largest HII region (diffuse emission nebula containing ionized hydrogene) has obtained a NGC number of its own: NGC 604 (William Herschel’s H III.150); it is situated in the northeastern part of the galaxy; apparently the bright knot near the top of our image. This is one of the largest H II regions known at all: it has a diameter of nearly 1500 light-years, and a spectrum similar to the Orion nebula M42. Hui Yang (University of Illinois) and Jeff J. Hester (Arizona State University) have taken a photograph of NGC 604 with the Hubble Space Tepescope, resolving over 200 young hot massive stars (of 15 to 60 solar masses) which have recently formed here. M33 was among the first “spiral Nebulae” identified as such by William Parsons, the Third Earl of Rosse; see his drawing. It was also among the first “nebulae” identified as galaxies, in which Cepheid variable stars were found; Edwin Hubble published a fundamental study in 1926 (Hubble 1926).
40 Double Star Winecke 4 (WNC 4), M40 was discovered by Charles Messier in 1764 while searching for a nebula that had been previously reported by Hevelius in the 17th century. The nebula was never found, so this double star system was catalogued instead. M40 is actually a binary (double) star system. The two stars have a visual magnitude of 9.0 and 9.3. The two stars can easily be resolved (split) by a 100mm (4inch) refractor telescope, which to the naked eye, appear as one.
81 Bode’s Galaxy (nebula) spiral galaxy (type Sb), The constellation of Ursa Major is the site of a beautiful spiral galaxy known as M81. This is one of the easiest and most rewarding galaxies for the amateur astronomer. It is a bright object, at magnitude 6.8, and can be easily located with any optical instrument. Some say it can be spotted with the naked eye under dark skies and ideal observing conditions. M81 is the brightest member of a group of galaxies called the M81 group. This galaxy is believed to have interacted with its close neighbor, M82, at some point in the past. It was also the site of a supernova explosion in 1993. M81 is located approximately 12 million light years from Earth.
82 The Cigar Galaxy irregular galaxy, M82 is another member of the M81 group of galaxies found in the region of Ursa Major. This object is officially classified as an irregular galaxy. Its shape contains no discernable structure. It is believed that this galaxy’s core has suffered from a close encounter with its neighbor, M81. The elongated shape of this galaxy has earned it the name Cigar Galaxy. M82 is a strong source of infrared radiation. In fact, it is the brightest galaxy in the sky in infrared light. This galaxy is located about 12 million light years from Earth. Its close proximity to M81 makes it easy to find, although it is a somewhat disappointing sight in anything but the largest telescopes.
97 The Owl Nebula planetary nebula, The constellation of Ursa Major is the location of the famous Owl Nebula, M97. This planetary nebula got its name from the two round dark regions which resemble the eyes of an owl. It is one of the fainter objects in the Messier catalog with a magnitude of only 9.9. The structure of M97 is unusually complex for a planetary nebula. It is illuminated by a 16th magnitude star at its center. As with most planetary nebulae, its distance is not certain. Best guesses place it at about 2,600 light years from Earth. This dim object requires a large telescope for any serious viewing.
101 The Pinwheel Galaxy spiral galaxy (type Sc), The constellation of Ursa Major if the site of a spiral galaxy known as M101. This a nearly face-on spiral with a bright center and symmetric shape. It is located about 27 million light years from Earth. With an estimated linear diameter of over 170,000 light years, this is one of the largest disk galaxies known. M101 is a bright object with a magnitude of 7.9. It is easily visible in binoculars and small telescopes, but an instrument larger than 4-inches is required to see any evidence of the galaxy’s faint spiral arms.
102 may be a Duplication of M101 M102 is the last of the “missing” Messier objects. There is some uncertainty as to whether the galaxy pictured here is M102. Due to an 18th century error, M101 may have been misclassified as M102. It is widely believed that M102 may be a lenticular galaxy located in the constellation Draco. It is a is a dim object with a visual magnitude of only 9.9 and can be hard to find without dark skies and ideal observing conditions.
108 spiral galaxy(type Sc(s)III) M108 is a spiral galaxy located in the constellation of Ursa Major. It is oriented nearly edge-on to our line of sight, which gives it an elongated visual appearance. This galaxy is unusual in that is has no pronounced central core and the disk is mottled with dark dust lanes. Its distance from Earth is believed to be about 45 million light years. In spite of this galaxy’s visual magnitude of only 10, it is considered an easy target for amateur astronomers. Its details can be seen even in small instruments.
109 spiral galaxy (type SBb(rs)I), The constellation Ursa Major is the site of a spiral galaxy called M109. It is classified as a barred spiral. The elongated shape of its central core can be seen even in small instruments. This galaxy is located about 55 million light years from Earth and is believed to be receding from us at a whopping 1142 km/sec. It was the site of a supernova in 1956 that reached a magnitude of 12.8. M109 is easily visible in small instruments where its bright central region appears pear-shaped. Larger instruments will reveal more detail. Discovered by Pierre Méchain in 1781. M109 is one of the “Theta”-like barred spirals, which appears as a “hazy spot” situated just 40′ SE of the mag 2.44 star Gamma Ursae Majoris (Phad, or Phecda). This object was observed by Pierre Méchain on March 12, 1781, and by Charles Messier on March 24, 1781, together with M108 when he measured M97. Messier listed the object now called “M109” under number “99” in a preliminary manuscript version of his catalog without a position, and Méchain mentioned it in his letter to Bernoulli of May 6, 1783. But together with M108, it was not added to the “official” Messier catalog until 1953, by Owen Gingerich. William Herschel has found this galaxy independently on April 12, 1789, and cataloged it as H IV.61 (incorrectly misclassifying it as a planetary nebula). Kenneth Glyn Jones has erroneously misclassified M109 in his General Description chapter 1 as type Sb, while in the galaxy description, he correctly gives its class (Hubble type) as SBc. M109 is about 7-by-4 arc minutes in angular extent, and of apparent visual magnitude 9.5 or 9.6. Visually, only its bright central region together with the bar can be seen, and appear pear-shaped in smaller telescopes, “with a strong suspicion of a granular texture” (Mallas). According to Brent Tully’s Nearby Galaxies Catalog, M109 is about 55 million light years distant, as it is receding at 1142 km/sec, and a member of the Ursa Major Cloud, a giant but loose agglomeration of galaxies. Tully took individual distances from the redshift in a model taking the Virgo-centric flow into account. The distance of this galaxy, however, may be a bit smaller, as the average recession in this cloud is lower, and some part of the surplus may be peculiar velocity.
49 elliptical galaxy (type E1 or S0_1(1)), M49 is a small elliptical galaxy located in the constellation Virgo. It was the first member of the Virgo cluster of galaxies discovered by Messier in 1771. At a magnitude of 8.4, it is also the brightest of these galaxies. M49 is believed to be about 160,000 light years in diameter, and is located approximately 60 million light years from us. It will be visible as a faint point of light with binoculars. Large telescopes will reveal the fuzzy, nebulous nature of this object, as well as its bright center.
58 spiral galaxy (type Sab(s)II), The Virgo constellation is home to a small galaxy known as M58. This galaxy is classified as a barred spiral due to its elongated shape. It is one of four such objects in the Messier catalog. M58 is one of the brightest members of a cluster of galaxies known as the Virgo cluster. Its distance from Earth is around 60 million light years. As with most distant galaxies, it requires a large telescope and excellent observing conditions to show any detail. An 8-inch or larger scope will reveal the galaxy’s barred shape as well as a hint of its spiral arms.
59 elliptical galaxy (type E5), Another member of the Virgo cluster of galaxies is M59. It is an elliptical galaxy about 90,000 light years across and is located some 60 million light years from the Earth. This is one of the larger elliptical galaxies in the Virgo cluster. The shape of this galaxy is quite flattened in appearance. With a magnitude of only 9.6, M59 is not a very suitable target for binoculars. Even in large telescopes it is only visible as an elongated fuzzy blob.
60 elliptical galaxy (type E2 or S0_1(2)), M60 is a large elliptical galaxy that is also located within the Virgo cluster of galaxies. It is the eastern most galaxy in the cluster. This galaxy is believed to be around 120,000 light years in diameter. It is located about 60 million light years from Earth. M60 is one of the brighter members of the Virgo cluster. It can be found with binoculars, but is not a very impressive sight. Telescopes will reveal the galaxies bright central core. As with most ellipticals, it will only be visible as a fuzzy blob.
61 spiral galaxy (type Sc(s)I.2), Located in the constellation of Virgo, amidst the cluster of galaxies know as the Virgo cluster, is a spiral galaxy known as M61. This is one of the larger galaxies in the cluster, measuring in at about 100,000 light years in diameter. It is estimated to be located some 60 million light years from Earth. Messier originally mistook this object for a comet. This galaxy’s low luminosity, about magnitude 10, makes it appear as nothing more than a fuzzy spot in small optic instruments. A large telescope and good sky conditions are neded to see any amount of detail.
84 elliptical or lenticular galaxy (type SB0_2/3(r)(3)), The constellation Virgo is the location of a small and dim galaxy known as M84. It was originally thought to be an elliptical galaxy. But more recent evidence suggests that is it actually a face-on lenticular galaxy. Lenticular galaxies are characterized by a disk shape with no conspicuous structure. M84 is a member of the Virgo cluster of galaxies, which contains a total of 16 galaxies in the Messier catalog. This galaxy was the site of a supernova in 1957 and two others in 1980 and 1991. It is located about 60 million light years from Earth. With a magnitude of only 9.1, it is best suited for viewing with a large telescope.
86 elliptical galaxy (type E3 or S0_1(3)), Yet another lenticular galaxy to be found in the Virgo cluster is M86. This is a large, bright object that some believe may actually be an elliptical galaxy. It is surrounded by an extremely faint system of globular clusters. M86 is located at the heart of the Virgo cluster and lies about 60 million light years from Earth. It forms a close group with another large galaxy, M84. Unlike many of the other galaxies in this cluster, M86 is actually approaching us at the blinding speed of 1500 km/sec. It is believed that the high gravitational field of this massive cluster of galaxies is responsible for M86’s unusually high velocity. At magnitude 8.9 this galaxy can be located with binoculars on a good night, but the best observing will be done with a telescope.
87 Virgo A elliptical galaxy (type E0), with Smoking Gun, In the heart of the Virgo cluster of galaxies lies a giant- and in its heart lies a monster. This elliptical galaxy is larger than our galaxy as it is 120,000 light years in diameter. However, since it is spherical in volume astronomers estimate that this ball of stars weighs in at over 2 trillion solar masses (sunlike stars!). In this image many small fuzzy balls surround the galaxy. Each of these is a globular cluster which contains hundreds of thousands of stars. And finally the seemingly innocuous spike eminating from the core of the galaxy is a luminous stream of accelerated gas (almost the speed of light) having been driven from a black hole in the heart of M87. There are many companion galaxies that orbit this overbearing galaxy.
89 elliptical galaxy (type E0), M89 is also a member of the incredible Virgo cluster of galaxies. This is an elliptical galaxy and is almost exactly circular in appearance. It is not known if it is actually circular in shape or if it is an elliptical in shape viewed end-on. This galaxy is unusual in that is appears to be surrounded by a type of enveloping structure which extends 150,000 light years from the galaxy. It also features a jet-like structure which extends over 100,000 light years. M89 is located some 60 million light years from Earth. At a magnitude of only 9.8, it is best suited for viewing with a large telescope.
90 spiral galaxy (type Sab(s)I-II), Also to be found in the constellation of Virgo is a spiral galaxy known as M90. This is one of the larger spiral galaxies in the Virgo cluster. It is located about 60 million light years from Earth and is approaching us at a speed of 383 km/sec. Its visual appearance is that of a tightly wound spiral with smooth, bright spiral arms. It is believed that the only active star formation is taking place within the dark dust lanes near the center of the galaxy. M90 has a visual magnitude of only 9.5, making it a tough target for binocular observers. Large telescopes will provide the best viewing.
104 The Sombrero Galaxy spiral galaxy (type Sa+/Sb-) NASA’s Hubble Space Telescope has trained its razor-sharp eye on one of the universe’s most stately and photogenic galaxies, the Sombrero galaxy, Messier 104 (M104). The galaxy’s hallmark is a brilliant white, bulbous core encircled by the thick dust lanes comprising the spiral structure of the galaxy. As seen from Earth, the galaxy is tilted nearly edge-on. We view it from just six degrees north of its equatorial plane. This brilliant galaxy was named the Sombrero because of its resemblance to the broad rim and high-topped Mexican hat. At a relatively bright magnitude of +8, M104 is just beyond the limit of naked-eye visibility and is easily seen through small telescopes. The Sombrero lies at the southern edge of the rich Virgo cluster of galaxies and is one of the most massive objects in that group, equivalent to 800 billion suns. The galaxy is 50,000 light-years across and is located 28 million light-years from Earth. The famous sombrero galaxy is located within the constellation of Virgo. Its designation is M104. This edge-on spiral galaxy got its name from the sombrero hat-like appearance. It is the first object in the catalog that was not included in the original publication. Messier added it by hand to his personal copy in 1781. M104 is characterized by a dark dust lane that spans the length of the galaxy’s disk. It is located about 50 million light years from Earth. This object can be located with binoculars but is best seen in a 4-inch or larger telescope.
27 The Dumbbell Nebula planetary nebula, Commonly known as the dumbbell nebula, M27 was the first planetary nebula to be discovered. It is a shell of gas that was expelled from the nebula’s central star. This object gets the name “dumbbell” from its hourglass, or dumbbell-like shape. Its distance is estimated to be about 1,250 light years from Earth. A 13th magnitude star at the center of the nebula illuminates it from within. M27 is the brightest and most impressive object of its kind, and with a magnitude of 7.4 can be easily seen using any optical instrument.
Last Modification: March 02, 2006