So cool....![hr style="width: 100%; height: 2px;"]
Today's set of image releases from the Mars Reconnaissance Orbiter HiRISE team included this one, of a fairly bland-looking lava plain to the northeast of Arsia Mons. Bland, that is, except for a black spot in the center.
What's that black spot? It's a window onto an underground world.(Click for full size picture)
[a href="http://planetary.org/image/PSP_003647_1745_RED_4m.jpg[/img]
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This black spot is one of seven possible entrances to subterranean caves identified on Mars by Glen Cushing, [a href="http://astrogeology.usgs.gov/About/People/TimTitus/" target="caves"]Tim Titus[/a], [a href="http://www.caveexplorer.org/vitae.php" target="caves"]J. Judson Wynne[/a] and [a href="http://www.mars.asu.edu/christensen/" target="caves"]Phil Christensen[/a] in [a href="http://www.lpi.usra.edu/meetings/lpsc2007/pdf/1371.pdf" target="caves"]a paper they presented at the Lunar and Planetary Science Conference in March[/a] (PDF format, 322k). Here's the figure from their paper that shows the seven caves, which they refer to by the names Dena, Chloe, Wendy, Annie, Abbey, Nikki, and Jeanne.
You can see the slightly scalloped edge of a hole on the flank of Mars' Arsia Mons (left),
but no amount of image enhancement (right) can bring out any further details inside the hole.
That means that the walls of the cave are overhanging -- the cave is larger below the ground than the entrance we can see at the surface --
and that it is very, very deep.
Full story: [a href="http://planetary.org/blog/article/00000984"]http://planetary.org/blog/article/00000984[/a]
