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Is it clear at HQ?

Posted by HQA on October 1, 2012 - 12:30pm

We are getting serious about installing telescopes at HQ.  As a precursor to actual observing, we’ve installed a Moonglow Technologies all-sky camera, purchased through the generosity of CCD School attendees. You can view its images, day and night, on the All-Sky Cam website.  It is fun to see how often it is clear in the northeast when it is cloudy in New Mexico!  This week is an exception, though they promise us that it will clear by Tuesday. In this urban environment, you don’t see many stars, but the clouds are easy to detect as they are lit from the ground.  You can also see the 280-foot radio tower of WJIB, a low power AM station in Cambridge.  We often notice hawks using that tower as a lookout during the summer, ready to pounce on any mouse that forgets to look up.

We are experimenting with several all-sky cameras.  We have an SBIG unit at Dark Ridge Observatory (New Mexico), providing support for APASS-north.  An Orion StarShoot All-Sky camera will be shortly heading to CTIO to give cloud information for APASS-south.   The calibration survey needs exceptional skies, so nightly animations help us understand why the photometry is poor on some nights as a few wisps of cirrus cross the sky.  The proof is in the actual photometry, of course, but it is nice to have confirmation that a discrepant measure was due to clouds.  The Moonglow, for example, takes images continuously, but you can select how often you want to archive them (say, every minute, 5 minutes, etc.).  They provide the website for uploading a small animation of the stored images, and software that morphs the all-sky image into a horizon view.  The time-lapse snapshot at the bottom is useful, as it shows you in a single glance the past couple of days of  cloud cover.  We’ll probably move the public access to our own website sometime in the future.

In the meantime, enjoy our little cloud-viewer!

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