Wednesday, June 19, 2019

BOOM! Mars takes a hit.

Beautiful isn't it?

That's a fresh crater on the surface of Mars, in the Valles Marineris region. It's about 15-16 metres (49-53 feet) wide and was created sometime between the 18th of February 2017 and the 20th of March 2019. Nobody can be sure of the exact date, let alone time, because we're reliant on the Mars Reconnaissance Orbiter (MRO), a spacecraft in a near polar orbit of Mars taking high-resolution pictures of the surface, and it takes a while to cover the same ground twice as the planet spins beneath it.

You can also look at a before-and-after gif here on this Twitter feed. It's hard to miss!

It was created by a rock about 1.5m (5 feet) wide smashing into the planet from space. Something that size would either burn up or be shattered by Earth's atmosphere, but the Martian atmosphere is so thin that such rocks can get through, although there is plenty of crater evidence that it can break them up, probably those that hit at a shallow angle and have a longer re-entry time.

You can get a sense of how it hit because the impact wave stands out clearly - a dark zone where dust was shifted off the surface. Beneath that dust is probably basalt rock, based on what's known of Mars geology and the colors showing in the image. There also are zones with a bluish tint, which may or may not be exposed ice. It seems unlikely because Valles Marineris is in the equatorial zone of the planet, which is warmer, but you never know for sure.

Perhaps NASA just found the next landing zone for one of its future rovers?


Adolf Fiinkensein said...

Excellent post, Tom!

Tom Hunter said...

Thanks Adolf. It's just a pity we don't have more commentators who like science enough to contribute in the comments. :)

Anonymous said...

Another good post Tom, I don't normally comment on astronomy, because I don't know much about it.


Lord Egbut Nobacon said...

Please Tom, a lot more like this.....gets us away from boring NZ politics and Veterans obsession with the Jones boy.....we agree on this at least.

Kimbo said...

@ Eggie

Does debating the flat earth theory count as science? 🙂

Tom Hunter said...

I reckon it does as it forces people to rethink an issue they just take for granted and perhaps do a little bit of old-fashioned science as well.

I must say I'm disappointed that YouTube's latest stupid tweaks to their AI tech have resulted in Flat Earther videos being pulled. Harmless stuff really.