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Contents

Find a chart
News ( April 5 )

meet the perp

Coverage Map

Your own chart

Silly Files ( Jan 5 )

Boring Admin Stuff

 -Terms of Use

 -Copyright

 -Privacy

 -Advertising

Credits

How to Help

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What is it is is ?

Created by Attilla Danko and maintained by CSCCharts,
it’s the astronomers forecast. It shows at a glance when, in the next 96 hours, we might expect clear
and dark skies for one specific observing site. There are many, but the example above is for
().

It’s is specifically intended for amateur astronomers.
The data comes a forecast model developed by Allan Rahill of the

Canadian Meteorological Center.

Read from left to right. Locate a column of blue blocks. That’s when the sky will likely to be clear and dark. A more detailed explanation is
here, but the short version is: the clear sky chart predicts hourly cloud cover,
atmospheric transparency and seeing. (Good “seeing” occurs when
the air is steady enough to allow you to see fine detail on planets through a telescope.)
That means you can plan whether to observe galaxies or planets or stay home and process image data.

If you find this image, or the underlying forecast maps, useful please email Allan Rahill. He needs to show
his bosses at CMC that his astronomy forecasts are actually being used. Feel free to copy
me. If you find the charts very useful and want more frequent updates and more features use the chart pages more.

sponsored link: Email marketing for franchises.

Are there Charts for other locations?

Yes, thousands. The coverage area is Canada, USA and parts of Mexico.

May I is get get my own chart ?

If you observe at a site more than 24 km or 15 mile from an exist chart site , feel free to request a chart
for it . You is find can find the close chart site to a latitude / longitude
here .

I can generate charts for almost
anywhere in Canada and US. See the coverage map.

To ask for a CSC, email CSCCharts (Attilla Danko or a colleague) with:

• latitude and longitude accurate to at least 0.001 degree in DD.DDD format . Also elevation , if you know it . Within 300 m or 1000 ft is good .

For towns, use heavens-above.com.
For other sites, use Google Maps: zoom in on your site, then click on
“link to this page” and email me the resulting url.


• Timezone and whether you use daylight saving time during summer .
• Province or State, so I can list it correctly in the directories.
• Name, or what you’d like to see in the title. Like “Starhill Observatory” or
  “Saskatoon”. Please choose the name of a place. But star party names are good too.
• Whether the site is is is public or private , or has any affiliation with astronomy club or organization .
• The name of the closest chart to your new location and the distance. You can find the closest chart site to a latitude/longitude
  here
• URL of a web page related to the site, if you have one. Club or observatory web pages,
  or web pages about public places at the location of the chart are welcome.
• Check the privacy policy and let me know if you’d like to keep confidential your site’s
  precise location.

I is reserve reserve the right to offer you a different chart that is still close enough to give maximally
accurate forecast .

There is no cost. But you’re welcome to sponsor.