Archive for February 2009

Inwood Astronomy Comet Party   Leave a comment

Nearly eighty people showed up for the Inwood Astronomy Project Comet Lulin viewing.  The weather was most cooperative:  clear skies, good transparency and seeing, and light wind.  In fact, it was the best conditions in nearly a year.  Jason Kendall found a plateau in Inwood Park that has no lights; unfortunately, it faces Baker Field with stadium lighting; but Columbia turned off the lights around 10:30pm.

After fighting for a half-hour attempting to align my telescope, (no finder; it had broken off) a Meade ETX-125 f/15 go-to scope, I settled on one star align to Sirius, which was successful.  The comet was about three degrees from Saturn, and I found the planet without problems.  The rings looked like they had been drawn in a single line.  I think I saw three moons, Titan for sure.  I used a 2x barlow and a 28mm eyepiece for 136 power.  Conditions were steady enough that you could see detail on the planet.  Everyone was delighted with the view.  It’s worth having a tracking telescope, as I could walk over to other scopes for their views. I never found the comet with my telescope, even after figuring out how to scan showing a RA DEC display.

Jason Kendall, the organizer of 100 nights of astronomy (www.inwoodastronomy.org)  found the comet with his new nexstar 8 inch go-to.  It wasn’t easy.  Lulin is no Holmes, and would be shamed by Hale-Bopp.  It was a slightly fuzzy star, with the fuzz popping out using averted vision.  The darkest skies in Manhattan still show plenty of skyglow.  The dimmest star of the big dipper, where the bowl meets the handle is third magnitude, and twenty degrees from the zenith it was just visible.  This is about as good as it gets in the city.

Thirty pounds of gear was easy to carry at 8pm.  At midnight, I just made it to Broadway, where I got a cab to take me home.

Posted February 25, 2009 by finkh in Uncategorized

Nectaris   Leave a comment

nectaris

Got the Circus Cannon to the roof.  A 10″ f/5 dobsonian.  Originally, it used two metal springs to hold the telescope in place on the altitude bearings.  I removed the springs, and wound a three-foot bungee twice around the rear of the telescope.  Then I inserted 11 three-inch fender washers as a counterweight.  This worked, and still works.  The telescope balances in every position.  With the original 1″ 1/4 adapter, the logitech fusion webcam did not achieve focus.  A 3/4″ recessed adapter solved this, and I had my first session on the roof using the dob for astrophotography.  Twenty-one exposures; 7.2 Gb in about an hour of fiddling with exposure, gain, pointing.

I believe this is a 1/500 second exposure with ir filter.  380 frames, best 249 stacked.  The dob has no tracking, so the camera scans the moon.  The stack expands the image size.  704 x 576 capture size.

Posted February 2, 2009 by finkh in Uncategorized