http://antwrp.gsfc.nasa.gov/apod/ima...hirise_big.jpg
A Hole in Mars
Credit: NASA,
JPL,
U. Arizona Explanation: Black spots have been discovered on Mars that are so dark that nothing inside can be seen. Quite possibly,
the spots are entrances to deep
underground caves capable of protecting
Martian life, where it to exist. The unusual hole pictured above was found on the slopes of the giant Martian volcano
Arsia Mons. The above image was captured three weeks ago by the
HiRISE instrument onboard the
Mars Reconnaissance Orbiter currently circling
Mars. The
holes were originally identified on lower resolution images from the
Mars Odyssey spacecraft, The above hole is about the size of a
football field and is so deep that it is completely
unilluminated by the Sun. Such holes and
underground caves might be prime targets for
future spacecraft,
robots, and even the next generation of
human interplanetary explorers.