Monday, October 20, 2008

Addition of Clear Sky Charts

Did anyone notice the Clear Sky Charts located at the bottom of our page? They are a new addition to the blog - but "what the heck is that???" Clear Sky Charts give astronomers a fairly accurate picture of what the sky will be like when they plan to stay up all night observing. There are plenty of people who have planned to go out and observe all night, get their equipment set up, and are ultimately disappointed when the clouds roll in and there is nary a star in sight. Those people could have avoided their frustration had they checked a Clear Sky Chart for their area! If you click on the pretty blue boxes you will see that they take you to a larger, more detailed, chart that can tell you what the weather/seeing will be over the next 24-36 hours. It will tell you how clear the sky will be, how much the image distortion will be, as well humidity and temperature ranges. You will also notice the difference between the two Clear Sky Charts that I've included on this blog.

The Peck Farm chart is for Peck Farm in Geneva, IL - the home base of the Fox Valley Astronomical Society. While the colored blocks are 'pretty' in the grid - the dark blue blocks are the ones that tell us at a glance that the skies will be dark and clear. The Peck Farm chart has very few of those - as it doesn't have very dark skies at that sight, and we have lots of clouds and humidity in the Midwest. This translates into not being able to see as many pretty things in the sky, which is the goal afterall, right?!

Conversely, the Kitt Peak chart (located southwest of Tucson) is almost always dark blue blocks. That is why there is a National Observatory there - great, dark, cloudless, night skies! While professional astronomers may complain that there is too much light pollution even in the Kitt Peak area, for those of us from the "Peck Farm Park region" of the country - we have never seen such glorious sights!

Do click on the rows of blocks at the bottom of the page, and see the comparison yourself!

1 comment:

Andrew Cooper said...

Miss the clear sky clocks! A great resource when planning that outing. Every bit of information was useful when deciding to load the gear up and drive an hour or two out into the dark.

The CSC coverage does not extend out to Hawai'i. But we do have an excellent forecast done by the UofH just for the observatories on Mauna Kea. It includes detailed cloud cover and seeing forecasts. Since I live in the shadow of the mountian it can be used at home as well.