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Use SQL to find moving objects (open in new window)

1. Go to the SQL Search tool (link opens in a new window). From the astronomers' main page, look under Search Tools. From the public main page, look under SkyServer Tools, then Search.

2. In the main window, type the following query (or use the query box at the bottom of this page):

   SELECT top 100 objID, sqrt( power(rowv,2) + power(colv, 2) ) as velocity

   FROM PhotoObj

   WHERE (power(rowv,2) + power(colv, 2)) > 50

   and rowv >= 0 and colv >=0

   The query returns the object ID and velocity for each of 100 objects seen to be moving. It selects only those objects whose velocity is high enough to be consistent with an asteroid. You can save the query as a CSV (comma-separated value) file by selecting CSV from the Output Format menu of the SQL Search tool. CSV files can be opened by most graphing programs.

3. You now have a sample of 100 objects that appeared to be moving through the sky when the SDSS imaged them. You can use another tool to view the moving objects.

Next: View the moving objects

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