Caves on Mars: close-up
If you remember back to March you may remember that I mentioned the discovery, with THEMIS on Mars Odyssey, of possible open-top caves on the flanks of Arsia Mons. THEMIS had a resolution of about 18m in the images. Now (via Cumbrian Sky via Emily's Planetary Blog) a new image from the HiRISE instrument on Mars Reconnaissance Orbiter shows one of those proposed cave entrances with a full resolution of 25cm per pixel!

Possible cave entrance on the flank of Arsia Mons, Mars CREDIT: NASA / JPL / U. Arizona
I must admit that these big holes sent my mind back a few years to the time I read First Men in the Moon by H.G. Wells. In that story, the main characters find an alien race (Selenites) living below the surface of our Moon. The beings had huge shafts connecting them to the surface that were covered in lids during the lunar night but let creatures called mooncalves out during the lunar day. I'm not saying that this hole is inhabited now, but for future Martian settlers, building your base underground may be a handy way to protect against harmful cosmic rays.






Comments: Caves on Mars: close-up
Ahhhh can you imagine some future rover approaching that, folding back up, re-inflating some stowed airbags and toppling in! Thud? Splash? Squish?
Posted by Rob on Friday 25th May 2007 (16:17 UTC)
It would probably be a thud, but a squish would be an interesting result.
Posted by Stuart on Friday 25th May 2007 (16:27 UTC)
Wow, that is really amazing! It's just so... black! Odd's on it's the entrance to a lava tube, some of entrances to the lava tubes I've seen in Victoria are not dissimilar in their abruptness.
Posted by Ian Musgrave on Sunday 27th May 2007 (11:53 UTC)
More likely, it's a silo. The Martians use it to launch missiles, shooting down our various spacecraft.
;-<
Posted by Stephen on Tuesday 29th May 2007 (13:40 UTC)
Waw...Cool
looks like asteroid or meteorite hit the surface of the earth's north pole
Its really amazing..a circle..nearly a circle
so the next question is how did this hole formed..whats inside it
Posted by Mundhir on Tuesday 29th May 2007 (14:10 UTC)
it's not a hole.
it's a lake.
http://img145.imageshack.us/my.php?image=laghinemiqa5.jpg
Posted by luca on Saturday 16th Jun 2007 (07:16 UTC)
Luca, it can't be a lake of water because liquid water can't exist for any length of time on the surface of Mars. It very quickly sublimates (changes into a gas).
Posted by Stuart on Saturday 16th Jun 2007 (21:39 UTC)
What about a lake of Oil. Now that would make everyone sit up.
Posted by Jon on Monday 09th Jul 2007 (12:33 UTC)
Perhaps its a black hole?
Posted by stan burden on Tuesday 18th Sep 2007 (19:25 UTC)
check out
http://palermoproject.com/Martian_Stains.html
it shows another image of this hole from a different angle.
if you look at the inner shadow there is a cresent that indicates the deapth of the crust at this point as being about 50 to 80 meters.
also the inner rim is very smooth.
it really does look as it this hole hase been punch OUT. The only problem with this is were is the debry.
the only answer is that the force that made this whole must have being so great that the debris was pulverised.
the key reason for saying that the hole was punched out the the conical fracturing at just around the top rim of the hole.
even when you use a drill to make a hole in a cement wall, the side from which you are drilling is a perfect circle but the other side of the wall allways has some cracking where the stone cannot tsuport the force applied behing it.
this hole was definitely made from bellow.
Posted by adrian riwnyj on Thursday 15th Nov 2007 (16:18 UTC)
its not a hole, just a black point
Posted by tk on Saturday 21st Mar 2009 (17:41 UTC)
If the hole was created by a meteor or something similar. it would be a lot more shallow and it would create a crater. this holes walls go straight down...
this is something else. who knows, maybe we discovered cave dwellers (just kidding)
Posted by mario on Monday 15th Jun 2009 (15:57 UTC)
Isnt that where the Sandworms live?
Posted by me on Wednesday 23rd Jun 2010 (15:26 UTC)
Its a bug hole from starship troopers! D:
Posted by my names is not important xD on Monday 06th Jun 2011 (02:25 UTC)
volcanoes are known for any mineral wealth and we havent got to that ,but ill guess any late life might find refuge there
Posted by paul riggatoni on Monday 06th Jun 2011 (08:15 UTC)