Indian Summer’s Eve
Last night was a night for star gazing. So I took out the family’s trusty 80mm apo (that’s Apo-Chromatic refractor, for those new to astronomy) and enjoyed an evening that started at 5:00 pm (thank you, EST!) at about 70 degrees F. There were some cirrostratus clouds, but they dissipated as if on command as I was assembling the telescope mount. The moon was just under 4 days old, already low in the west, with Venus barely 5 or 6 degrees to its north. Very pretty.
I watched the moon for about 30 minutes, noting dots of mountain tops where the crescent became needle thin, until I could see features on the ‘dark side’, showing faintly under the earth-shine. I was a little surprised that I could see these features even under high power (125x in my ‘scope).
The sky was a little rough – boiling – early on. But rather suddenly it calmed in the west, giving good views. Venus is featureless, but showed as a nice half-circle, about 12 or 15 arc-seconds in size. It’s going to get a lot larger in the coming months.
The highlight of the night was Mars. By that time about half a dozen from our local Astronomy Club had joined us, but I was the first to notice Mars low in the eastern sky (hey! It’s bright enough we all thought it was a plane at first!). Mars is only 5 or 6 days past its closest approach (to us) for the year (well, for the next eighteen months or so, actually), and it’s nearly as close as the historic pass of 2003, which was the closest approach of Mars in nearly 60000 years. I missed that one. Hum! I’m used to seeing Mars as a small, nearly featureless dot in my ‘scopes. But not last night. Mars is usually disappointing to amateurs, especially the first time they see it. That’s because Mars isn’t really that big a planet (not compared to Jupiter, Saturn or even Uranus, which are much farther away), and Mars usually is not so close. Its orbit carries it up to five times farther away from the Earth than it is now, so usually Mars is so tiny that it’s very hard to see features on its surface. Last night it was about 20 seconds of arc in diameter, and I easily spotted a significant dark patch that sat north to south about half a hemisphere in length, and maybe a tenth in width. Very cool. I strained to make out anything resembling polar ice caps, and I may have spotted one (but it was probably wishful thinking).
Anyway, the 2x barlow lens and the filters that Tom let me borrow really helped bring out the dark patch (especially the #25 wratten (red) filter). Mars wasn’t even 30 degrees above the horizon (so I was looking through a lot of air), but the view was nice and steady.
Lastly, I took a look at the Pleides, the famous, bright open cluster of stars often mistaken for a small cloud on winters’ nights. Sparkled like jewels! The eastern sky was just steady (um, a lesson I’ve learned over the years is that the most transparent skies are often not the best, because the air just isn’t still. Slightly opaque skies, like last night, can be much steadier, and that counts for alot). I need to check my best chart, but I was seeing down to about 9th magnitude under low power. Not too bad in an area where the “Great DC Nebula” wants to dominate the entire southern sky.
By 8:00, the temperature had dropped to about 60 degrees, and the dew fell out of the sky. That’s a wrap. What I didn’t even try to find (though I wanted to) was Uranus. I couldn’t make out Aquarius to give me a guide to it (too much light-gunk to the south), so I’ll have to try again next time.