Wednesday, February 26, 2014

Chairface Chippendale Could Not Be Reached for Comment...

Space Rock Smacks Moon, Creating Biggest Lunar Explosion Ever Seen
Pow! That would be the sound of a giant rock smacking into the moon (if the moon had any atmosphere to carry the sound, of course). But you can imagine the burst coming from the explosion in the video above, the biggest lunar impact ever observed from Earth.

Our natural satellite gets pummeled fairly regularly by tiny micrometeorites and occasionally by bigger space rocks. In May 2013, scientists recorded what was then the biggest explosion that had been seen on the moon when a 40-kilogram boulder slammed into the lunar surface at about 90,000 kph. Now, telescopes have recorded the impact from a meteorite weighing 10 times as much, whose flash was briefly as bright as the light from Polaris, the north pole star. The burst occurred on Sept. 11, 2013 in a area on the moon called Mare Nubium and was probably created by a meteor between 0.6- and 1.4-meters wide. The impact generated a crater with a diameter of around 40 meters.
Why, yes, there *is* video!



Just... DAMN. Thanks, moon, for taking the hit for the team. That asteroid would have made quite a mess of things here on ol' Terra. Apparently the moon gets smacked around a bit by space debris, which naturally begs the question of why we haven't been nailed a time or two by something the size of what killed off the dinosaurs...

Enjoy the rest of your day, and don't think about giant killer space rocks...

That is all.

7 comments:

Bubblehead Les. said...

Weird. So it happened on Sept 11TH and we're just finding about it now?

Stand by for a Tin-Hat Konspiracy Explosion in 3..2..1..

Phssthpok said...

SPOOOOOOOOOoooon!

Dave H said...

The meteor that exploded over Chelyabinsk last year was estimated to be about 20 meters in diameter. If that rock that hit the Moon struck Earth instead, it'd make an impressive light show but not a lot of damage on the ground.

Anonymous said...

It does happen fairly frequently on the geological time clock.

http://scribol.com/science/10-greatest-major-impact-craters-on-earth

Gerry

ProudHillbilly said...

What Anonymous said - it's a matter of perspective time-wise.

Ron Larimer said...

The answer is atmosphere

Geodkyt said...

Dave -- it totally depends on meteorite composition, speed, and reentry angle.

A 20m meteor is likely to airburst at 73,000 feet or so (for a measly 230kt) if it comes in at a shallow angle -- as the Chelyabinsk impactor did. Which still caused $30 million in damage at about 1500 casualties (including over 100 requiring hospitalization), despite detonating at an inordinately high alititude and not directly over a heavily populated area.

Note that the usual "impact crater" estimates for meteors you see that say at a given size, if a meteor will ground strike and if so, what size crater it will leave generally assume a specific speed, angle, density, and composition. For exmple, the one on Wikipedia assumes an average "stony" meteroid (density given hints they assume a chondrite, which makes sence as these are the most common impactors -- but they aren't as dense as an iron or iron-nickle, and are FAR more likely to come apart in atmosphere) at 17km/s at 45 degrees.

A 20m iron or iron-nickle meteorite that comes in at a steep angle will end up hitting the surface. And it will hit hard.