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M51 brightness question

  • 03-05-2010 1:38pm
    #1
    peterako
    Registered Users, Registered Users 2 Posts: 720 ✭✭✭


    It was beautifully clear last night so I decided to try again to find M51 (The Whirlpool Galaxy).

    I THINK I found it....

    But....

    How bright/clear/definded should it appear in my 130mm reflector?

    It looked like two faint stars close enough together with a grey/white haze around them.

    Highest mag I could get last night was 65x, any higher and the image was too dim.

    Even at 65x I had to 'avert' my eyes to get a decent look.

    I THOUGHT I could just make out a 'swirly' pattern, but that coudl just have been my mind trying to fit in the Stellarium images I had looked at earlier.

    On a brighter note (pun intended).
    I think I saw the ISS for the first time last night at about 11.30pm.
    Wow! It was BRIGHT!
    Looked pretty impressive through my binoculars! Even to the naked eye.

    Peter


Comments

  • #2
    Popoutman
    Registered Users, Registered Users 2 Posts: 1,363 ✭✭✭Popoutman


    peterako wrote: »
    It looked like two faint stars close enough together with a grey/white haze around them.

    That's the one. That's as good a description of what most people see at a first look.
    As you spend more and more time studying whatever you are looking at, different details will become more visible, as you look at and around the object and you end up painting a picture in your head of what the details are. Most people will take upwards of 10-20 minutes of looking at something before they stop seeing more details. It's worth noting that all of the details in something like M51 are extremely subtle in any average sized scope. When I'm looking with my 8" it takes a few minutes to start seeing the spiral arms, and even then they are not the most obvious.
    If you have dark skies you may get to see hints of the spiral structure after 5-10 minutes or looking around and at it in your 130mm.
    peterako wrote: »
    Even at 65x I had to 'avert' my eyes to get a decent look.
    This is one of the most important techniques for seeing detail in dim astronomical items at night. It's worth practising this skill to see detail 'out of the corners of your eye' to see where your eye is most sensitive. For me it's between the centre of vision and the point of my nose, for other people it's between the centre of vision and their temple. This skill will help you with things like driving and also when walking around at night.


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