Explosion on Moon Spreads Moondust

Jotii writes "NASA scientists have observed an explosion on the moon. The blast, equal in energy to about 70 kg of TNT, occurred near the edge of Marethe Sea of Rains on Nov. 7, 2005, when a 12-centimeter-wide meteoroid slammed into the ground. The main danger of such explosions is the static and toxic moondust, which is thrown around."

Comments

Danger?

[Tx]

The main danger of such explosions is the static and toxic moondust, which is thrown around.

Danger to whom exactly? Should I be hitting the bunker to dodge that toxic moondust?

How do they know the size and speed of the object?

[MichaelSmith]

Obviously they can calculate the objects kinetic energy from the intensity of the flash. This will give them mass or speed, but not both. Perhaps the speed came from their assumption about the origin of the meteoroid, but that could still be wrong, of course.

BTW if anybody is interested in exactly what it was like to be walking on the moon in the 60's and 70's I recommend they have a look at the Apollo Lunar Surface Journal

Toxic moondust, eh?

[wampus]

1. Who did NASA feed the moondust to to determine it is toxic?
2. If you are inside on the moon, one would presume the dust isn't
3. If you are outside on the moon and this happens, you just had 70kg of TNT dropped on you. Getting exploded is your primary concern, followed by death, with moondust toxicity being an also ran

This is why you should keep your helmet on

[harlows_monkeys]

For the foreseeable future, any life on the moon will be in a spacesuit that is completely sealed, or inside a building or ship that is completely sealed. So, would toxic moondust be a problem?

I suppose one might have to be careful when opening an airlock, lest moondust enter the airlock and then spread to the inside of the ship, but without an atmosphere, any dust blown up will settle quickly, so a simple rule of not opening an airlock right after anything nearby explodes should be sufficient.

Or is the risk that it will get on the outside of suits, and be hard to clean off, and so will be carried in?

Re:Not an explosion ...

[pnewhook]

a rock slamming into another rock does not cause an explosion

Yes it does. The force of the impact is great enough that it vaporizes the ground around it. This molten rock cloud then expands and rapidly cools releasing a huge flash of light as it does so. In short an explosion, albeit one without sound.