March 17, 2010: Backyard asteroids

Bill Maney

I was curious how deep I could go from my driveway (in Emerald Hills near 280 and Edgewood Rd.), since I'd like to try to see a quasar from there and the easiest one is Mag 12.8. So I tracked down some asteroids. A few weeks ago I chose Angelina in cancer and Europa (the asteroid, not the moon), which were relatively easy in the 12.5" f/5 dob, "Pachabel".

On Wednesday night I took advantage of the nice weather to find two more. I chose Philomela at magnitude 12.0, and Leda at Magnitude 13.0. Philomela was overhead in Gemini, and Leda was nicely placed in the dark part of my sky (SW toward Edgewood Park, Woodside and the watershed) in Taurus. Finding and seeing Philomela was pretty straightforward. Leda was a different story. For Leda, I could not see it with a 25mm at all, but was finally able to see it with averted vision in a 10mm plossl. I'd read with skepticism about the "sky darkening" effect of higher magnification, but this was my first experience with a clear-cut case.

Last night I was able to track down those two again and verified that they moved. To my surprise, the dimmer one had moved way farther than the brighter one. One is probably much bigger or whiter than the other. Or maybe it's turning a retrograde corner.

The upshot is that I may have a good chance of seeing the quasar. The seeing was poor so I may be able to go a little deeper, but I think Pluto is not looking likely.

I also decided to hunt down Vesta, but when I went to make a finder chart from Sky Tools, it was so bright that I decided to just note the general area. It's in the sickle of Leo. Then I took my star chart and star-hopped around till I found the odd man out. This was kind of fun and made me feel a little more like an explorer and a little less like a tourist.

Bill Maney