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Can you tell the Physical Properties of a Messier Object?

  1. Jan 18, 2016 #1
    Can you tell any physical properties of a Messier object by its name, such as M1 or M42? I know this may sound like a silly question, but I am doing an Astronomy GCSE and I thought that maybe there was a better way of just looking it up online and remembering it.
  2. jcsd
  3. Jan 18, 2016 #2


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    No, you can't. The list was compiled at a time when nobody even had an idea what a galaxy is, so all those objects were just 'nebulae' (or, as Messier would probably explain to you: 'not comets'). If you look at the list of Messier objects, there's just no order to it: type, place in the sky, brightness, distance - all jump around pretty much randomly.

    I hope they're not expecting you to memorize all of them?
  4. Jan 19, 2016 #3
    Thanks. I was just wondering if there was an easier way.

    Ha! I sure hope not!
  5. Jan 19, 2016 #4
    One simple rule of thumb, though: the first 45 M objects are generally brighter than the rest.
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