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Shock Diamonds and Mach Disks Feature Summary

Type:
From Physics Research
Title:
Shock Diamonds and Mach Disks
Description:
When the speed of the gases in a jet or rocket exhaust exceeds the speed of sound, a dazzling pattern results called "shock diamonds" or "Mach disks," as shown in this photo of the SR-71 Blackbird. The diamonds are created by crisscrossing shock waves in the exhaust.

You can see shock diamonds in a static rocket test in this NASA video. For more information, check out Shock Diamonds and Mach Disks.
Image:
Image credit <a href=" http:// http://www.nasaimages.org/index.html" target="_blank">NASA</a>; <a href=" http://www.nasaimages.org/luna/servlet/detail/nasaNAS~8~8~62915~166812:Shock-waves-stream-from-the-exhaust " target="_blank">Image source</a>; <a href=" http://www.physicstogo.org/images/features/SR-71-large-3-9-10.gif" target="_blank">larger image</a>
Image credit NASA; Image source; larger image
Image URL:
http://www.compadre.org/Informal/images/features/SR-71-large-3-9-10.gif
Featured:
June 16, 2010 - July 1, 2010