Astronomy

Okay, temptation overtook me again . I pulled out the IR blocking filter and took an hour's worth of images, plus enough calibration frames that I should have been able to eliminate the flaws in the previous images. The results, below, are better, but there are a few nagging issues.

The weather was just too clear last night to avoid the temptation, so I dragged out my equipment and started taking pictures. Admittedly, almost anything done from here in Brooklyn, "pretty-picture" wise, has to be considered practice since it rarely works out unless its the moon or planets. But I thought I would try either the Veil Nebula or something in Cygnus with a deep red filter, which blocks most of the city lights, and use it as a black-and-white image.

I just saw this one in the March issue of Science and Children, and it's something I definitely have to incorporate into the moon phase activities I do with the kids. The original comes from the Top Science web site, and while I've enjoyed their short ads in the magazine, I never looked at their web site. Definitely a good resource. (I'm resisting the urge to whip out the credit card and buy a bunch of stuff...for now anyway).

I've had several people ask me whether I went out to look at the full moon on March 19. Uhm, no, I didn't. Why not? After all, it made the local (radio) news as "supermoon" since it was going to be closest it has been in nearly 20 years.

It's been a while since we had an astronomy club at PS102, but we're back! Most of the sessions are repeats but since the original class that took them is now in 7th grade, that shouldn't bother you. In fact, you're getting a better deal since it means the activities are tried, improved, and in some cases, corrected. Ahem, the original activity for constructing a 3-D model of the Big Dipper had the stars labeled in the wrong order: how embarassing!

Today is the day when Earth makes its closest approach to the Sun, around 2pm EST (New York time). If you live in the northern hemisphere, you might find it surprising that the Earth is closer to the Sun during winter than during summer, but it is. The difference in distance is "small," astronomically speaking, a bit under 5 million kilometers. Our most distant point from the Sun will happen on July 4th.

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I originally built these models a couple of years ago, but didn't realize it was something "novel" until I got some comments at this past year's NEAF where I had brought them for the children's section. Quite frankly, I think it works well with adults, too, as I've heard some well-educated adults propagating common misconceptions about what causes the phases of the moon. The idea is simple enough. One side of the moon is illuminated by the Sun, the other is not.

It's been a busy year. I bought this at NEAF back in April and have only just now been able to get out and give it a spin. The new feature, of course, is the autoguiding. With the original TT320, the specifications state a periodic error limit of 5 arcseconds per 5 minutes. As it works out, when using my Borg 45ED lens, the pixels in my Canon 350D are about 5 arcseconds wide. What I've seen is that I can, with great care, get exposures up to 4 minutes long, but some of them invariably show trailing and have to be thrown out.