conceptFEATURED CONCEPT: Dark Matter
Unlike ordinary matter, dark matter does not emit or absorb light--or any other type of electromagnetic radiation. Consequently, dark matter cannot be observed directly using a telescope or any other astronomical instrument that has been developed by humans. If dark matter has these strange properties, how do we know that it exists in the first place?
Like ordinary matter, dark matter interacts gravitationally with ordinary matter and radiation. Astronomers study the distribution of dark matter through observing its gravitational effects on ordinary matter in its vicinity and through its gravitational lensing effects on background radiation. The background image shows the bullet cluster, a famous example where the visible matter does not follow the mass distribution.
Combining all the available evidence, dark matter represents about 83% of the matter content of the universe. Read more about dark matter on this web page. Let us know your questions and comments on the message board.
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I'm a survivor of a brain tumor since '94, but in spite of that, I'm
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newsNEWS

Recent updates and fixes to the project
May 6, 2012
As part of the recent updates (more storage, more recent kernel) we finally fixed a longstanding problem: the community preferences are now working again! Check out our main post on the message board for the project announcements.
New featured concept: Dark Matter
April 17, 2012
We updated the featured concept to Dark Matter, with a cool image of the bullet cluster. At the bottom of the featured concept on the home page there is a link that will take you to a thread on the message board where you can comment and ask questions. Enjoy!
Server upgrade complete.
April 10, 2012
After installation of 4TB of disk space and a re-organization of the file system, and a few updates and bug fixes, such as updating the data base to fix an annoying and persistent problem with setting user preferences, we are back in production. Thank you for your patience and keep crunching!
We\'re back.
March 2, 2012
We are running again, with a temporary fix for the disk space problem. 4 TB of disk space have been ordered. The team data base has been repaired. We will keep you updated when the filesystem upgrade happens, which we will take as an opportunity for a few additional updates.
Assimilator not working - update 1.
February 7, 2012
As some of you have pointed out, we are currently experiencing problems with the file system which are affecting the module that assimilates the results of your computations. We are working to resolve these problems and will endeavor to keep you updated as we progress. Please bear with us as we try to resolve this problem.
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