A NEW IMAGE OF AN ELONGATED impact crater in the southern hemisphere of Mars hints at a violent origin. Scientists think it could have been carved out by a train of meteoroid projectiles striking the planet at a shallow angle.
The image above was captured by the European Space Agency’s (ESA) Mars Express spacecraft on 4 August 2010, and the smallest objects distinguishable by the camera are about 15m across.
The unnamed crater sits just to the south of the much larger Huygens basin (see image at right). It is about 78km in length, opens from just under 10km wide at one end to 25km at the other, and reaches a depth of 2km.
Impact craters are generally round because the projectiles that create them push into the ground before the shockwave of the impact can explode outwards. So why is this one elongated?
The clue comes from the surrounding smattering of material, thrown out in the initial impact. This ‘ejecta blanket’ is shaped like a butterfly’s wings, with two distinct lobes. It hints that two projectiles, possibly halves of a once-intact body, slammed into the surface here.
And the formation of this sort of elongated feature is not finished. In a few tens of millions of years, the Martian moon Phobos will plough into the planet, breaking up in the process, and likely creating new crater chains across the surface.
Adapted from information issued by ESA / DLR / FU Berlin (G. Neukum) / NASA / MGS / MOLA Science Team.
Get SpaceInfo.com.au daily updates by RSS or email! Click the RSS Feed link at the top right-hand corner of this page, and then save the RSS Feed page to your bookmarks. Or, enter your email address (privacy assured) and we’ll send you daily updates. Or follow us on Twitter, @spaceinfo_oz
Like this story? Please share it…