"Triad" on Mars rock photographed by Spirit near Gusev crater
2004 03 01
Center of large rock has triad of dark "circles." Image taken by Spirit rover's
right Front Hazard Camera Non-linearized Full frame EDR acquired on Sol 55 of Spirit's
mission to Gusev Crater at approximately 13:48:37 Mars local solar time.
Image credit: NASA/JPL
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