Skywatching
It may be late April, but last night was the first clear, moonless night of the year which didn't require me to be heavily bundled up.
It had been a while, so I first shook off the rust by observing some of backyard astronomy's "greatest hits", which I learned to find last year: The Hercules Cluster, Bode's Galaxy, and the "Cigar Galaxy". Then I went in search of new (for me) objects.
First up, the Pinwheel Galaxy, M101. Trying to observe this is a bit like trying to see M33, which I still haven't conclusively spotted. As deep sky objects go, it's pretty large, and my astronomy software says it's magnitude 8.5--the same as Bode's. But its so-called "surface brightness" is low and it doesn't have a visually dense core. This amateur photo illustrates the problem pretty well. When you're on the edge of a big metro area, like I am, those spiral arms are hopelessly invisible to the naked eye. I would probably see them with a long photographic exposure. You might think I could see the core pretty easily, but even Bode's core, which is pretty bright (another amateur image), appears to me as a faint grey smudge.
After re-checking its position three or four times, I did finally see M101: a hazy patch of sky ever-so-slightly brighter than the sky around it.
The pleasant surprise of the night was M108, which my software says is a magnitude 11.0 object. I've never spotted anything higher than 10.0, so I was expecting to see a whole lot of nothing, but I actually found it on the first try. In my scope, it's an oblong smudge, a bit like the Cigar Galaxy but not quite as bright. Indeed, the SEDS page says, "M108 is quite easy for the amateur, easier than the published values of its brightness."
Tonight is also supposed to be good for observing. I think I'll start by re-sighting M108, then I'll look for its neighbor, The Owl Nebula, which is going to be tough. I'll also take another crack at M33. After that, I'll make it up as I go. :)
It had been a while, so I first shook off the rust by observing some of backyard astronomy's "greatest hits", which I learned to find last year: The Hercules Cluster, Bode's Galaxy, and the "Cigar Galaxy". Then I went in search of new (for me) objects.
First up, the Pinwheel Galaxy, M101. Trying to observe this is a bit like trying to see M33, which I still haven't conclusively spotted. As deep sky objects go, it's pretty large, and my astronomy software says it's magnitude 8.5--the same as Bode's. But its so-called "surface brightness" is low and it doesn't have a visually dense core. This amateur photo illustrates the problem pretty well. When you're on the edge of a big metro area, like I am, those spiral arms are hopelessly invisible to the naked eye. I would probably see them with a long photographic exposure. You might think I could see the core pretty easily, but even Bode's core, which is pretty bright (another amateur image), appears to me as a faint grey smudge.
After re-checking its position three or four times, I did finally see M101: a hazy patch of sky ever-so-slightly brighter than the sky around it.
The pleasant surprise of the night was M108, which my software says is a magnitude 11.0 object. I've never spotted anything higher than 10.0, so I was expecting to see a whole lot of nothing, but I actually found it on the first try. In my scope, it's an oblong smudge, a bit like the Cigar Galaxy but not quite as bright. Indeed, the SEDS page says, "M108 is quite easy for the amateur, easier than the published values of its brightness."
Tonight is also supposed to be good for observing. I think I'll start by re-sighting M108, then I'll look for its neighbor, The Owl Nebula, which is going to be tough. I'll also take another crack at M33. After that, I'll make it up as I go. :)