I just about died rolling on the floor laughing over your typo. I consider bright to be anything over 8th magnitude. Sure, you'll be able to see fainter from your back yard, but the real faint stuff you can save for a dark site. Charles Messier saw all of his objects with the equivalent of an 8" scope from Paris. It wasn't as light polluted, but it was very air polluted from heating fires burning coal. You should be able to see 12th mag and fainter from a dark site. It will help if you keep your self dark adapted. Keep one eye (your observing eye) closed unless you are actuallly looking through the eyepiece. You can also put a coat, blanket, or other dark cloth over your head while you observe to keep out stray light. As far as size goes, 11X9 is one third the size of the full moon!. The moon is only 30 minutes of arc. Of course, you won't see the full extent of many galaxies because they are too faint in the extremeties. Also, an 8th magnitude galaxy is fainter than an 8th magnitude star. Extended objects like galaxies and nebulae are characterized by surface brightness. The magnitude rating is taking all of the light from an object and putting it into the size of a star. In other words, there is as much light in an 8th magnitude galaxy, bt it is spread out across the size of the galaxy making the surface brightness fainter. Your mirror is functioning as a 12.4 inch telescope with that chip taken out of it. This assumes that you have only masked the chip out and not the entire ring around the diameter of the mirror. You really should not see a bunch of difference with the chip gone. The descriptions in my books are from J. L. E. Dreyer's reference "New General Catalog" and the "Index Catalog" by the same author. They are not mine, unless they are in the text after the "description". The initials of those works should look familiar - NGC and IC. M62 would not have migrated into a new constellation due to precession. The constellation (constipation :>)boundaries also precess, so once the line is drawn, it moves with the stars. I am not sure of the reason why Burnham placed it in Scorpius. He may have had erroneous coordinates or ????? Your analogy of states is one I have used for years. The constellations are the states, and the stars are the cities within the states. If you want to go somewhere, you always check the map. The same is true of the stars. Keep looking up. Brent --- Jim Gibson <xajax99@yahoo.com> wrote:

Brent I like your 2 books, Finder Charts of The Messier Objects, with the Telrad positions. I have some questions about the descriptions though. First, a little explanation of where I am coming from. Using your charts I was able to locate M51. Needless to say it was considerably less thrilling a view than the cover picture on Burnahm's Celestial Handbook Vol. I. Although, to view it with a 11.3 inch mirror ( I figure that's what I have left after taking a big chip out of a 12.5 inch mirror) was still satisfying. The picture for me was not well resolved. The day had been windy and there was allot of dust in the air and the skys over Pleasant Grove are getting more light polluted by the day. I saw two fuzzys more separated than I expected after seeing the picture. Under the conditions described I was not able to see the spiral arms causing the appearance of widely separated fuzzys. In my mind I can still see two fuzzys (not well resolved), not really bright, but more than faint. I would call M65 - 66 faint from what I have seen. OK. now that you might better understand where my question is coming form, in your book I on page 50 under the heading M51 there is this word "Bright" describing an object of Mag 8.1 and of size 11' X 8'. Then in book II on page 37 under the heading M94 (which is just down the street from M51) there are the words "Very bright" describing an object of Mag 8.1 size of 11' X 9'. The question is, what constitutes bright? Is that “bright” if you are on top of Mauna Kea or do you need a full 12.5 inches in Pleasant Grove to see bright? Are all objects with the same magnitued rating just as easy/hard to see; say a galaxy vs. an open cluster vs. a star? Oh, and nebula too? I have only seen M65 - M66 from SPOC. So I am guessing that any object with a Mag of 9.0 or higher I may not be able to see from my backyard; heaven forbid I should use a filter. By the way, for some reason I was checking the number of Messier Objects in Scorpius in Burnhams and in your books. I noticed that there is a discrepancy of one. On page 1652 of Burnham’s handbook he lists M62 in Scorpius. You, on the other hand, have M62 in Ophiuchus. I figured since I was kind of teasing you above I had better end with due respect. You are right. According to Wil Tirion's SkyAtlas 2000.0 M62 is in Ophiuchus. Or was it in Scorpius when Burnham wrote the book (1979) and because of precession M62 is now in Ophichus? What is interesting though is in the SkyAtlas chart there is a dotted line that separates the area of the sky by name; kind of like states. The dotted line between Scorpius and Ophichus start about 18080s3001, or something, and as it continues west the line departs from the -30 degree line. I wonder why the cartographers didn't just follow the -30 degree line. Maybe they did originally and because of precession they had to move the dotted line. Anyway I think that's what caused M62 to end up just barely in Ophiuchus. I implied that the dotted lines move, but I don’t know that. Do the dotted lines move (the borders between constipations) because of precession and if not will the constellation Scorpio end up in Ophiuchus someday like the First Point of Aries now being in Pisces? That would be a mess. Jim

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