An Amateur's List Comparable to the Original By John A. Barra
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Most historians agree that Charles Messier discovered or confirmed only 100 objects. Others added to that list to make 110. Therefore, I tried to find 100 to match his 100. Where there was a dispute as to whether a certain object was actually a Messier object, I chose to resolve the disagreement in favor of inclusion. I want to make it clear that I am not attempting to create any official list. Rather, I am merely having fun to use my amateur skills to test my theory. PARAMETERS FOR SEARCH To test my theory as accurately as possible, I used the characteristics of the original 100 as parameters for my search. I included the same number of each type of object. I also made sure that all the objects in each category were as bright as the dimmest object Messier included for that type (see Table 1). The only exceptions were where there was only one object per category: supernova remnant, double star, asterism and star cloud. I did not search for any object lower in the sky than M7 (-34 39) in Scorpius, the Messier object with the lowest declination. For this reason, the list that I compiled differs from some of the more modern lists such as the Caldwell Catalogue. That list includes bright objects in the far southern hemisphere. Messier could not have seen those objects at his viewing latitude. Finally, all the objects I searched for had to be observable in my eight-inch Coulter Odyssey. I was able to view all of the original 100 with that scope at the Peoria Astronomical Society's dark-sky site 12 miles west of Peoria, Illinois. MY LIST OF THE SECOND 100 My theory proved to be correct. I was able to find another 100 objects as bright and remarkable as Messier's 100 using the same parameters. My list is shown in Table 2. Wherever possible I used The Deep Sky Field Guide to Uranometria 2000.0 by Cragin, Lucyk and Rappaport for statistical information. Magnitudes vary greatly from source to source. Therefore I used visual magnitudes rounded off to the nearest one-half. The first 10 objects I chose were the M101 to M110 included in most Messier lists. These objects were not discovered nor probably confirmed by Messier. However, they are remarkable enough to be included in anybody's list. The remainder, M111 to M200, are listed in order of right ascension. OPEN CLUSTERS My list contains 26 open clusters brighter than M26 in Scutum, the dimmest Messier with a magnitude of 8. Many were as spectacular as those in the original list. I must admit that it was difficult to narrow the list. Some people may disagree with my choices on open clusters. There are many others that fit within these parameters. The Double Cluster (M118, NGC869; M119, NGC884) in Perseus is the clear highlight of the open clusters. M46 and M47 in Puppis are almost as close together but not as impressive. I find that the trio of M36, M37 and M38 in Auriga, though further apart, is the most comparable group to the Double Cluster from the original 100. IC4665 (M163) in Ophiucus reminds of M39 in Cygnus in that both are bright and large, but sparse. On the other end of the spectrum, NGC1502 (M122) in Camelopardalis is a very compact cluster, similar to M29 in Cygnus. Each cannot be resolved with binoculars. However, you can follow a three degree chain of stars from NGC1502 with either your telescope or binoculars. This chain of stars is called Kemple's Cascade. GLOBULAR CLUSTERS AND GALAXIES Messier did account for most of the bright globular clusters. All 28 on my list are brighter than M72 in Aquarius, the dimmest of the Messier globulars. However, 22 on the original list were brighter than my brightest of such clusters at magnitude 8. None compared to M13, the Hercules Cluster or any of the other bright Messier globular clusters. In both lists globular clusters were predominate in the Ophiucus-Sagittarius region. There are 12 of these clusters from the original list in these two constellations, while 20 from my list can be found there. In fact, this region could be considered the Realm of Globular Clusters, similar to the Realm of Galaxies in Virgo in the Messier 100. Of the 32 galaxies that I found with a magnitude of 10 or lower, most compare well with the original list. None, however, were comparable to M31, the Great Andromeda Galaxy. But NGC 253 (M114) in Sculptor does stand out even though it is so low in our sky. This spiral is regarded as a beautiful object from places with a lower latitude. M104, the Sombrero Galaxy in Virgo, and NGC4565 (M145), the Needle Galaxy in Coma Berenices, are two outstanding edge-on galaxies. There are none comparable to them in the original 100. NEBULAE When I picked 10 nebulae, I was forced to put both planetary and bright nebulae in the same category. It seems that Messier choose almost all of the bright nebulae observable in amateur telescopes. Six of his ten nebulae are bright nebulae. I found only one such nebula bright enough to see with my telescope. It is NGC2261 (M128), Hubble's Variable Nebula in Monoceros. This nebula changes size and brightness over time. However, Messier did leave out most of the great planetaries, choosing only four. I added nine, eight which have common names and are regarded as classic deep-sky objects. Included among them are NGC2392 (M132), the Eskimo Nebula in Gemini, NGC6543 (M165) the Cat's Eye Negula in Draco, and NGC7662 (M199), the Blue Snowball Nebula in Andromeda. I also included my favorite, NGC6826 (M184), the Blinking Planetary in Cygnus. Your eyesight is fooled causing you to alternatingly see the nebula and its central star. THE OTHER OBJECTS The rest of each list consists of single objects in four different categories. I matched supernova remnant M1, the Crab Nebula in Taurus, with M192 (NGC6960, 74, 79, 92, and 95), the Veil Nebula in Cygnus-- the only other such object visible in my telescope. I did have to borrow my friend's nebula filter to see it in its real beauty. Since Messier had a star cloud in his list, M24 known as the Sagittarius Star Cloud, I had to choose one for my list. The Scutum Star Cloud seemed like a natural choice. It is given the number M177 and has no other numbered designation. I literally had thousands of double stars to choose from to correspond with Messier's M40. I picked another virtually unknown F. G. W. Struve 1315 (M134). Both pairs are in Ursa Major, are rather dim, and are easily split. Each star in the two has nearly the same brightness as its companion star. I also had many asterisms to choose from to match M73, the nondescript, four-star asterism in Aquarius. I finally choose CRR399 (M182), Brocchi's Cluster in Vulpecula, better known as the Coathanger. I say finally not because the Coathanger was a hard choice for the next 100. It is one of the most spectacular objects on my list. However, since most books on the subject called it an open cluster, I originally did so too and chose another asterism. The Hipparcos satellite made the decision easy when it recently determined that the Coathanger was indeed an asterism afterall. OTHER COMPARISONS There are many other comparisons on the two lists, both in terms of names and appearances. For example, Messier had M57, the Ring Nebula in Lyra, while my list includes the similar, but much larger M197 (NGC7293), the Helix Nebula in Aquarius. The original list has the M97, the Owl Nebula in Ursa Major, while I included M116 (NGC457), the Owl Cluster in Cassiopeia. The Wild Duck Cluster (M11) in Scutum is similar in name with M130 (NGC2301) the Great Bird of the Galaxy in Monoceros. This cluster, which has also been described as an airplane, does not look anything like the fan-shaped M11. On the other hand, the open cluster M200 (NGC7789) in Cassiopeia is a very faint version of the Beehive Cluster (M44) in Cancer. As you continue to stare at M200 in binoculars, you can see many stars appear as a swarm. The Coathanger (M182) resembles the Pleiades (M45) in Taurus in that they both can be seen with the naked eye, although their magnitude difference is apparent. Each list includes an open cluster that has a more famous bright nebula associated with it. M16 is an open cluster in Scutum more known for the Eagle Nebula (IC4703) included within it. M127 (NGC2244) is an open cluster in Monoceros more famous by the Rosette Nebula (NGC2237-9,46) that surrounds it. Both open clusters are easy to see. The nebulae are great photographic objects; however, they are difficult to see with amateur telescopes. Messier's list includes two planetaries named after dumbbells, the Dumbbell (M27) in Vulpecula and the Little Dumbbell (M76) in Perseus, while mine has two planetaries named after planets, the Saturn Nebula in Aquarius (M193, NGC7009) and the Ghost of Jupiter in Hydra (M138, NGC 3242). Messier's star cloud M24 has a faint open cluster imbedded within it (NGC6603), while my Scutum Star Cloud M177 also has a faint open cluster within it (NGC6608). Even their NGC numbers are nearly the same. Finally, I should note that two galaxies in my list team up with two pairs of galaxies from the original 100 to form galactic triangles. M65 and M66 in Leo are joined by M141 (NGC3628). M110, never documented by Messier, of course, teams up with M31 and M32 in Andromeda. Additionally, M105 is joined on my list with nearby M139 (NGC3384) to form the point of another triangle in Leo with M95 and M96. ANOTHER MARATHON? The list which I have compiled has proven my theory to be correct, at least to my satisfaction. Meanwhile, it provided a great deal of fun it viewing all these objects--which was probably the real goal of this task. As I mentioned earlier, I do not attempt to make this list into any official list. But I certainly do not object if anyone wants to use it for his pure, viewing pleasure. If anyone might think about trying to make a marathon out of this list of the second 100, the best time would be in mid-March, the normal Messier marathon time. However, I feel compelled to add one last comparison. You will not be able to complete this list in one night either. From latitude forty degrees north, only 96 of the 100 will be viewable in one night. M113 in Cetus, M114 and M115 in Sculptor, and M197 in Aquarius will blocked out by the Sun. |
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