Stonyhurst disks - Wikipedia

The CorenSearchBot has performed a web search with the contents of this page, and it appears to include material copied directly from:

http://eo.nso.edu/dasl/Lessons/Stony/index.htm (Copyvios report)

It will soon be reviewed to determine if there are any copyright issues. The content should not be mirrored or otherwise reused until the issue has been resolved.

If substantial content is duplicated, unless evidence is provided to the contrary (e.g. evidence of permission to use this content under terms consistent with the Wikimedia Terms of Use or public domain status; see Wikipedia:Donating copyrighted materials), editors will assume that this text is a copyright violation, and will soon delete the copy. Before removing this notice, you should:

Check if CorenSearchBot is in error: If so, simply note so on this article's discussion page.
Replace the copyrighted text with your own work. Note that simply modified or rephrased text is still an infringement—to remove the copyrighted contents you will need to completely remove them and then write totally new text to replace it.
If you hold the copyright to this text and permit its use under the terms consistent with Wikipedia's policies, please see Wikipedia:Donating copyrighted materials for instructions on how to verify the licensing.
Replace the copyrighted content with a wikified reference.
Check whether it is reasonable to revert to one of the previous versions of the article
Remove the copyrighted content if it is not critical to the article.

A stonyhurst disk is used to determine the longitude and latitude of sunspots. The stonyhurst disk was discovered at the observatories in stonyhurst or stonyhurst college The Earth doesn't orbit exactly around the Sun's equator, so through the year the center of solar pictures moves up and down a little more than 7 degrees. This angle varies sinusoidally through the year and is called B0. Earth crosses the Sun's equator about December 7th and June 7th each year.

Sunspots and other features will rotate across visible light images along lines of latitude (unless they drift!). Stonyhurst disks are transparent overlays that match the size of whole-disk images of the sun. These disks provide a graphic means of locating sunspots on the solar disk in reference to lines of latitude and longitude.

This article needs improving if anybody would lie to improve this article click edit this page.