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Mars Express Booms All Deployed - Universe Today
All three MARSIS booms on Mars Express are now fully deployed, and the spacecraft is ready to begin searching Mars for underground sources of ice and water. The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) consists of two 20-metre (66 foot) and one 7-metre (23 foot) boom. Controllers turned on the radar and performed a brief test, but they're still planning on an extensive commissioning phase until July 4, when the instrument will be ready for full operations.