I've always wanted to practice astronomy toward scientific goals - pretty pictures are over done by my peers and achievable mostly with obscenely expensive equipment. I strive to build a stable and accurate telescope system to capture images from which meaningful data can be extracted - I'm not there yet, and a new single arm massive mount is completed to support a 14" Celestron optical tube assembly and the 8 inch newtonian; see here. The Starizona Hyperstar will allow imaging at F/2, an ultrafast system indeed.
Above is a light curve of the cataclismic variable IY Ursa Majoris. I had written my own code to determine the magnitudes but I couldn't compete with Maxim DL. After removing dark frames and flat fielding the 100 images with my s/w, the relative magnitude were extracted and plotted. The results are acceptable, but there is room for improvement; use a guide star to track, UBV filters, lower CCD temperature (had frosting problems). Images are from an Audine KAF0400E, binning 2x2, 120 seconds exposure at 0 degree centigrade. The raw and reference were shifted up to better see the result.
I wrote a Perl script to collect data daily from all Canadian and USA ClearSkyChart locations from the excellent service provided by Attilla Danko - some 4300 locations in all. When a good bucket full of the predictions is collected, a second Perl script reduces only the night collections to compile the best predicted sites for Astronomy in Canada and the USA as I plan on moving to such a location. The collection began in August 2011, and ended in February 2013.
These links are to the reduced data for monthly and yearly averages [yearly file includes light pollution map links]. Correlating the predicted data with satellite derived dark sky studies yields the favoured sites. It is by no means an exhaustive study as they are predictions and the locations are where other astronomy buffs have used telescopes from, most often near light polluting human settlements. The transparency and seeing were averaged only when the cloud cover was below 10%, so as not to skew the average and provide a more accurate appraisal of the quality of clear skies. "Clear Sky Hours" ignore the phase of the moon for obvious reasons. The hours are for the sampling period which was 1 year for USA locations and over 1.5 years for Canadian locations, thus hours shown are total accumulated over the period and so percentage of clear sky hours column is a better indication of overall site quality. The Bortle scale is shown in the yearly file - they were derived from the pixel *colour* from the North American pollution map from the "Cinzano et al" effort [not the snow corrected maps done later by Lorentz which I did not use on account of it missing most of Canada] - when the Bortle scale is shown as *unknown*, it is due to the station's latitude/longitude was off the light pollution image, or resolved to a colour off from the expect scale due to geopolitical or water boundary lines in the image - note this data is from 1996-1997 satelite imaging and it is likely that it has worsened for sites closest to cities and towns.
Much gratitude to Attila for his support.
Notes:
1) Excel hyperlinks to the "Dark Sky Finder" maps usually centers on the location, but not always - if your mouse pointer hovers over a point on the map having a tag/description/comment, it may displace the view, so keep your pointers initially off the map. Use the Google map's zoom bar on the left size of the map to zoom in to the site's location rather than your mouse scroller to prevent this map relocation issue.
2) Many sites having unknown Bortle values are due to the latitude and longitude not provided by the ClearSkyChart data.
The absolute best sites? They are all Bortle scales of 1, have % of clears skies above 50% (as high as 75%), and average seeings above 3 (most above 4). In order, from the best at the top.
Mesquite Springs, California
San Pedro Martir Observatory, Baja California
Equuleus South Baja, California
Monte Cristo's Castle, Nevada
Grand Canyon (North Rim), Arizona
Gila Cliff Dwellings National Monument, New Mexico
Alkali, Nevada
Rachel, Nevada
AGS Observatory, New Mexico
Top Of The World Observatory, New Mexico
Shuttleview Observatory, New Mexico
Monument Valley, Utah
Okie-Tex Star Party, Oklahoma
Black Cliff, Nevada
Lunar Crater, Nevada
Boulder, Utah
Wind River Special Observatory, Wyoming
Goblin Valley State Park, Utah
Great Basin National Park, Nevada
Natural Bridges National Monument, Utah
Willard L. Eccles Observatory, Utah
WYA Eastern Lassen Site, California
Texas Star Party, Texas
Stokes Castle, Nevada
Marathon, Texas
McDonald Observatory, Texas
Persimmon Gap, Texas
Lajitas, Texas
Nebraska Star Party, Nebraska
Telescope Array Long Ridge FD, Utah
Aquarius Ranger Station, Utah
Black Rock Desert, Nevada
Summer Lake Hot Springs, Oregon
