Lunar Geminids

Jan 04, 2007
Lunar Geminids
Lunar impacts since Nov. 2005. Numbers 14-16 and 19-20 are Geminids. Number 18 is a probable Geminid. Credit: NASA Meteoroid Environment Group.

Another meteor shower, another bunch of lunar impacts... "On Dec. 14, 2006, we observed at least five Geminid meteors hitting the Moon," reports Bill Cooke of NASA's Meteoroid Environment Office in Huntsville, AL. Each impact caused an explosion ranging in power from 50 to 125 lbs of TNT and a flash of light as bright as a 7th-to-9th magnitude star.

The explosions occurred while Earth and Moon were passing through a cloud of debris following near-Earth asteroid 3200 Phaethon. This happens every year in mid-December and gives rise to the annual Geminid meteor shower: Streaks of light fly across the sky as rocky chips of Phaethon hit Earth's atmosphere. It's a beautiful display.

The same chips hit the Moon, of course, but on the Moon there is no atmosphere to intercept them. Instead, they hit the ground. "We saw about one explosion per hour," says Cooke.

How does a meteoroid explode? "This isn't the kind of explosion we experience on Earth," explains Cooke. The Moon has no oxygen to support fire or combustion, but in this case no oxygen is required: Geminid meteoroids hit the ground traveling 35 km/s (78,000 mph). "At that speed, even a pebble can blast a crater several feet wide," says Cooke. "The flash of light comes from rocks and soil made so hot by impact that they suddenly glow."

Cooke's group has been monitoring the Moon's nightside (the best place to see flashes of light) since late 2005 and so far they've recorded 19 hits: five or six Geminids, three Leonids, one Taurid and a dozen random meteoroids (sporadics). "The amazing thing is," says Cooke, "we’ve done it using a pair of ordinary backyard telescopes, 14-inch, and off-the-shelf CCD cameras. Amateur astronomers could be recording these explosions, too."

Indeed, he hopes they will. The NASA team can't observe 24-7. Daylight, bad weather, equipment malfunctions, vacations—"lots of things get in the way of maximum observing." Amateur astronomers could fill in the gaps. A worldwide network of amateurs, watching the Moon whenever possible, "would increase the number of explosions we catch," he says.

To that end, Cooke plans to release data reduction software developed specifically for amateur and professional astronomers wishing to do this type of work. The software runs on an ordinary PC equipped with a digital video card. "If you have caught a lunar meteor on tape, this program can find it. It eliminates the need to stare at hours of black and white video, looking for split-second flashes."

More data will help NASA assess the meteoroid threat as the agency prepares to send astronauts back to the Moon.

Source: by Dr. Tony Phillips, Science@NASA

Explore further: Some astronauts at risk for cognitive impairment, animal studies suggest

add to favorites email to friend print save as pdf

Related Stories

Building BICEP2: A conversation with Jamie Bock

Mar 18, 2014

Caltech Professor of Physics Jamie Bock and his collaborators announced on March 17, 2014 that they have successfully measured a B-mode polarization signal in the cosmic microwave background (CMB) using the ...

Young stars cooking in the Prawn Nebula

Sep 18, 2013

The glowing jumble of gas clouds visible in this new image make up a huge stellar nursery nicknamed the Prawn Nebula. Taken using the VLT Survey Telescope at ESO's Paranal Observatory in Chile, this may well ...

NASA: Flash reports consistent with single meteor

Mar 23, 2013

(AP)—Reports of a flash of light that streaked across the sky over the U.S. East Coast appeared to be a "single meteor event," the U.S. space agency said. Residents from New York City to Washington and ...

Recommended for you

Kazakh satellite to be launched into orbit

2 hours ago

Kazakhstan's first-ever Earth observation satellite is to be fired into orbit next week from the European spaceport in Kourou in French Guiana, launch company Arianespace said.

Habitable exoplanets are bad news for humanity

5 hours ago

Last week, scientists announced the discovery of Kepler-186f, a planet 492 light years away in the Cygnus constellation. Kepler-186f is special because it marks the first planet almost exactly the same size as Earth ...

First-of-its-kind NASA space-weather project

21 hours ago

A NASA scientist is launching a one-to-two-year pilot project this summer that takes advantage of U.S. high-voltage power transmission lines to measure a phenomenon that has caused widespread power outages ...

User comments : 0

More news stories

Habitable exoplanets are bad news for humanity

Last week, scientists announced the discovery of Kepler-186f, a planet 492 light years away in the Cygnus constellation. Kepler-186f is special because it marks the first planet almost exactly the same size as Earth ...

Kazakh satellite to be launched into orbit

Kazakhstan's first-ever Earth observation satellite is to be fired into orbit next week from the European spaceport in Kourou in French Guiana, launch company Arianespace said.

Professional and amateur astronomers join forces

(Phys.org) —Long before the term "citizen science" was coined, the field of astronomy has benefited from countless men and women who study the sky in their spare time. These amateur astronomers devote hours ...

First-of-its-kind NASA space-weather project

A NASA scientist is launching a one-to-two-year pilot project this summer that takes advantage of U.S. high-voltage power transmission lines to measure a phenomenon that has caused widespread power outages ...

Genetic code of the deadly tsetse fly unraveled

Mining the genome of the disease-transmitting tsetse fly, researchers have revealed the genetic adaptions that allow it to have such unique biology and transmit disease to both humans and animals.

Ocean microbes display remarkable genetic diversity

The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion billion billion of the single-cell creatures live i ...