Posted on 06/14/2006 6:37:50 AM PDT by steve-b
There's a new crater on the Moon. It's about 14 meters wide, 3 meters deep and precisely one month, eleven days old.
NASA astronomers watched it form: "On May 2, 2006, a meteoroid hit the Moon's Sea of Clouds (Mare Nubium) with 17 billion joules of kinetic energythat's about the same as 4 tons of TNT," says Bill Cooke, the head of NASA's Meteoroid Environment Office in Huntsville, AL. "The impact created a bright fireball which we video-recorded using a 10-inch telescope."
Lunar impacts have been seen before--"stuff hits the Moon all the time," notes Cooke--but this is the best-ever recording of an explosion in progress:
The video plays in 7x slow motion; otherwise the explosion would be nearly invisible to the human eye. "The duration of the fireball was only four-tenths of a second," says Cooke. "A student member of our team, Nick Hollon of Villanova University, spotted the flash."
Taking into account the duration of the flash and its brightness (7th magnitude), Cooke was able to estimate the energy of impact, the dimensions of the crater, and the size and speed of the meteoroid. "It was a space rock about 10 inches (25 cm) wide traveling 85,000 mph (38 km/s)," he says.
If a rock like that hit Earth, it would never reach the ground. "Earth's atmosphere protects us," Cooke explains. "A 10-inch meteoroid would disintegrate in mid-air, making a spectacular fireball in the sky but no crater." The Moon is different. Having no atmosphere, it is totally exposed to meteoroids. Even small ones can cause spectacular explosions, spraying debris far and wide....
(Excerpt) Read more at science.nasa.gov ...
If a rock like that hit Earth, it would never reach the ground.
Huh.
No, but I'm going to start rounding up suckers, um... bettors myself, as this sounds like a bet you can't lose.
No life found? We just haven't located it yet.
Got microbes? Jackpot!
From Space.com:
Poring over images on his home computer taken by the now-orbiting Mars Global Surveyor (MGS), Clarke said that there are signs of vegetation evident in the photos.
"I'm quite serious when I say have a really good look at these new Mars images," Clarke said. "Something is actually moving and changing with the seasons that suggests, at least, vegetation," he said.
Clarke is a brilliant guy, and I personally agree with the notion that science fiction and science fact are very often separated by little more than time. However, given what is known about the Martian climate and surface conditions, I am still having a hard time with the idea that there are current, active species of vegetation there.
Based on his description, it seems more likely that what he is seeing are changes in the surface coloration produced by drifting dust and sand, not vegetation. I have not yet been able to track down any of the images to which he refers, so I don't know, just a supposition.
Why is there a fireball? A flash due to ionization as kinetic energy is transferred seems likely, but a fireball would seem to have substantial duration.
I assume they're referring to the rapidly dissipating cloud of vaporized meteoroid/moonrock as a "fireball". It wouldn't behave the same as a fireball in atmo, of course.
Moonbases potentially hardest hit.
Steven Hawking is in the news with his recommendation that we colonize outer space. Clarke turned his back on colonization of outer space decades ago--contributing, along with Sagan, to the 30-year siesta of the space program--and therefore should be ignored. Hawking is a great guy, although when he descends to the level that we ordinary people can understand he is taking vital time and energy away from his theoretical physics.
space ping.
Hey, some of the bugs growing in my nickel plating solution would grow just fine on Mars. Other earthling extremophiles would do well in volcanic vents, etc. on Mars.
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Moon Unit Zappa unaccounted for!
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