Step outside this evening and look up high in the southeastern sky for a bright yellow star. That's Saturn. Just to the right and above it, you'll see a small, fuzzy patch of green. That's Comet Lulin (C/2007 N3). It is now at its closest approach to Earth, speeding by on its way out of the Solar System. Although it's at its peak brightness and appears closest to Saturn tonight, it will still be visible for a while so if you miss the show tonight so you still have time to catch it.
If you live in an urban area, you might have a tough time spotting Lulin. To get a really good view of it, especially under light polluted skies, you need binoculars or a telescope. If you don't have a that kind of equipment or it's cloudy where you live you can still see live images over the web.
To start with, check out the Comet Lulin webcast at the Coca-Cola Space Science Center at Columbus State University. They have live webcam images that updated every 15 seconds throughout tonight.
If you want to see Lulin (whether tonight or in the coming weeks) and you think you might enjoy remote access to professional telescopes at an affordable price, go check out Slooh. They have a site in the Canary Islands, one in Chile and another one under construction in Australia. You can purchase 100 minutes of viewing for $14.95 or just check things out (including the ability to control the telescopes) with their 7 day free trial. And tonight they are highlighting Comet Lulin; see the mission schedule here.
Since we've got poor seeing tonight, my plans to get out with my camera and telescope fell through so I've spent the evening following the comet at Slooh. Here's a shot I saved a while ago.
Hopefully, we'll have clear skies in the next couple of days so I can get some shots with my own equipment but, in the mean time, it's great to have access to someone else's gear.
For more information on Comet Lulin, check out these sites: