Gregoria Luna's Astronomy Blog

There was some pretty good seeing conditions last night, so I took my dob out for a few hours until things started to get uncomfortably dewy.

We've all seen the advertisements for cheap toy telescopes advertising 400x Power! 700x! 10,000x POWER! And if you do a little reading you'll probably have found out these claims are hogwash. Yes, you can technically enlarge an image in a telescope by whatever factor you want if you have barlow lenses and short-focus eyepieces. But a telescope's maximum magnification is related to its aperture, and you can't do much better than 50x per inch or 2x per millimeter of aperture. So a 50mm toy telescope can't really get much better than 100x. Now you and I both know that this is only a rule of thumb. I had to do some digging around to get to the bottom of the problem, of where "2x per mm" etc comes from, why that's the limit, and why some people claim to get 3x per millimeter or better when discussing very fine telescopes.

Get your head out of the gutter. I've seen Uranus on several occasions at the Cline Observatory. I like to show it alongside planetary nebulae when I'm running sessions in the dome, to help explain to the public why they're called that, and because seeing all the planets is pleasant and nice. I've never found Uranus myself, though, and the night before last, while exploring the autumn skies with my 6" f/8 Dobsonian, I decided to give it a go.

Aperture fever rears its ugly head.

I love visual astronomy. It's probably the most fulfilling hobby I've ever had. Finding tough objects, appreciating the greats, and sharing those observations either in person through sidewalk astronomy and observatory viewing sessions or through recording them in my log. But sometimes I do think, "I'm just looking at fuzzy gray blobs and white and brown dots." And it doesn't really phase me. The result may not be the equivalent of an expensive astrophoto or hubble space telescope picture, but I'm using my own eyes, augmented through nothing but mirrors and glass, to view and record actual astronomical objects at great distances. I live to see as much detail and structure in the blobs and dots as I can, but I know the limitations of visual astronomy. But with laypeople on the sidewalk, or beginners with their new telescope, their expectations might not match those limitations, and it ends up with disappointment. However, if you know what to expect to begin...

I believe the Moon/Mars conjunction was October 2nd-3rd. Earlier that night I visited my grandma's house and I showed my cousin and my brother some constellations, as well as peeks at Jupiter, Saturn, and Arcturus using the Galileoscope. When we got home we could see the Moon & Mars peeking through the trees, they were very close.

 I've kind of dropped the ball with my blog this week. Here's a few updates, and some sketches too.