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?

Re:Danger?

[HermanAB]

Well, any moonestrials should be immune to moon dust... or maybe not, which would explain why there aren't any.

So, if you find yourself outside on the moon, without the luxury of a space suit, don't breathe in...

Re:Danger?

[DeathByDuke]

moon dust is heavily corrosive, its not fine grained smooth surfaced like the dust on earth, it hasnt been 'weathered' etc and so still has spikes etc on its surface. Apollo astronauts found it corroded a lot of their equipment and spacesuits due to the friction and the tearing properties of the dust.

Nasa has reason to be concerned since it could tear open a spacesuit or corrode a bases walls over time.

Re:Danger?

[pnewhook]

moon dust is heavily corrosive, its not fine grained smooth surfaced like the dust on earth

Actually it can be very fine grained. The closest analogy I've seen officially used for testing vehicles for the moon is fine dry Portland cement.

Dust on earth is primarily ash, flakes of skin, dust mites, and dust mite fecal matter, so moon dust is certainly not like earth dust.

In Other News: Research stolen. Lawsuit Pending

[Anonymous Coward]

"Moondust is electrostatically charged and notoriously clingy." --Dr. Tony Phillips, 2005

"But moondust will cover you. Cover you." --David Bowie, 1996

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

Re:How do they know the size and speed of the obje

[Inspector Lopez]

There is other information available.

For example, the date of the observation (7 November), and commentary in the article leads to the reasonable supposition that the observation was from a meteor in the Taurid stream http://comets.amsmeteors.org/meteors/showers/tauri ds.html. Since the Taurids are very well characterized, their orbital velocity is extremely well known, and thus the net impact velocity would be known with great precision, too. If it's one of the Taurids. Which is not so bad an assumption.

Even without the Taurid assumption, you can look at other data to put some bounds on the meteor velocities. For example, there are excellent "head echo" observations by some big radars:

Arecibo http://www.copernicus.org/EGU/acp/acp/4/947/acp-4- 947.pdf

Jicamarca http://www.copernicus.org/EGU/acp/acpd/3/6063/acpd -3-6063.pdf

and there have been several PhD dissertations in recent years exploring a variety of aspects of meteors, just from the plasma physics side (let alone the "meteor astronomy" side); check out Close and Dyrud from 2004 at BU, http://www.bu.edu/astronomy/alumni/phd.html.

The past decade has been a remarkably active time for meteor studies. There will be presentations about meteors at the URSI meeting in Boulder CO 4-7 Jan 2006, http://cires.colorado.edu/ursi/