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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."
Danger to whom exactly?
To the astronauts. The dust is poisonous, is flung rapidly, and sticks to the astronauts.
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There was an episode where a near-light speed object was headed toward earth and America and Russia panicked, until Russia saw that it was about to hit the moon instead. Even Russia thanked God for the moon's very existence when the end-of-the-world thingie actually did hit the moon and not Earth.
:D
(Of course, an alien intelligence intentionally fired it at the moon, but still)
It's not a matter of if some highly annoying rocks have been intercepted by the moon... it's more a matter of how many.
I for one am shaking my telescope with joy at my lunar masters.
--- Grow a pair, liberals... stop letting the Republicans bully you!
It's very well known that microscopic particles of dust can be very damaging to the lungs.
See Pneumoconiosis and Silicosis.
The dust is not a problem, it might become a problem, e.g. if more astronauts walk on the moon or if outposts are built, both of which are highly likely to happen.
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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.
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.
Tesla was a genius. Edison however was a overrated hack who liked to torture puppies.
An explosion doesn't have to be a chemical or nuclear reaction. When a small object collides with a large one at very high speed, a load of kinetic energy gets converted to heat in a small fraction of a second, melting and vaporizing a quantity of material. The high temperature generates very high pressure, and the hot matter proceeds to escape forcibly in every available direction. That's an explosion, and that's why meteor craters are bigger than the meteors that made them.
The only difference between this and a TNT explosion is the source of the energy.
rj
There is other information available.
i 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.
- 947.pdf
d -3-6063.pdf
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/taur
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
Jicamarca http://www.copernicus.org/EGU/acp/acpd/3/6063/acp
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/
Gene Shoemaker