Archive for the ‘Lunar science’ Category

Chinese Premier Wen Jiabao unveils Chang’e-2 pictures

November 8, 2010

Xinhua reports the success of the Chang’e-2 mission.

Chinese Premier Wen Jiabao Monday unveiled the first pictures of the moon’s Sinus Iridum, or Bay of Rainbows, marking the success of China’s Chang’e-2 lunar probe mission.

Chinese Premier Wen Jiabao attends an unveiling ceremony for pictures of the moon's Sinus Iridum, or Bay of Rainbows, taken and sent back by the Chang'e-2, China's second lunar probe, in Beijing, capital of China, Nov. 8, 2010. (Xinhua/Huang Jingwen)

The pictures were taken and sent back by the Chang’e-2, China’s second lunar probe, which was launched on October 1.

Chang’e-2 entered into its final 118 min orbit and formally started its mission of mapping the moon and preparing the way for Chang’e-3 on October 9th.

Lunar activity: Chang’e-2 starts mission and Nasa revives 2 satellites

October 29, 2010

Xinhua reports

Scientists successfully activated four attitude control engines on Chang’e-2 and sent the satellite into the orbit with a perilune of just 15 kilometer above the moon, according to a flight control official in Beijing. It will photograph the Bay of Rainbows region with its CCD cameras from Wednesday, according to the center.

NASA has revived 2 satellites that were dying and sent them to the moon creating the ARTEMIS mission:

A pair of NASA spacecraft that were supposed to be dead a year ago are instead flying to the Moon for a breakthrough mission in lunar orbit. “Their real names are THEMIS P1 and P2, but I call them ‘dead spacecraft walking,'” says Vassilis Angelopoulos of UCLA, principal investigator of the THEMIS mission. “Not so long ago, we thought they were goners. Now they are beginning a whole new adventure.”

The story begins in 2007 when NASA launched a fleet of five spacecraft into Earth’s magnetosphere to study the physics of geomagnetic storms. Collectively, they were called THEMIS, short for “Time History of Events and Macroscale Interactions during Substorms.” P1 and P2 were the outermost members of the quintet. Working together, the probes quickly discovered a cornucopia of previously unknown phenomena such as colliding aurorasmagnetic spacequakes, and plasma bullets shooting up and down Earth’s magnetic tail. These findings allowed researchers to solve several longstanding mysteries of the Northern Lights.

The mission was going splendidly, except for one thing: Occasionally, P1 and P2 would pass through the shadow of Earth. The solar powered spacecraft were designed to go without sunlight for as much as three hours at a time, so a small amount of shadowing was no problem. But as the mission wore on, their orbits evolved and by 2009 the pair was spending as much as 8 hours a day in the dark. “The two spacecraft were running out of power and freezing to death,” says Angelopoulos. “We had to do something to save them.”

Because the mission had gone so well, the spacecraft still had an ample supply of fuel–enough to go to the Moon. “We could do some great science from lunar orbit,” he says. NASA approved the trip and in late 2009, P1 and P2 headed away from the shadows of Earth.

With a new destination, the mission needed a new name. The team selected ARTEMIS, the Greek goddess of the Moon. It also stands for “Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s Interaction with the Sun.”

The first big events of the ARTEMIS mission are underway now. On August 25, 2010, ARTEMIS-P1 reached the L2 Lagrange point on the far side of the Moon. Following close behind, ARTEMIS-P2 entered the opposite L1 Lagrange point on Oct. 22nd. Lagrange points are places where the gravity of Earth and Moon balance, creating a sort of gravitational parking spot for spacecraft.

 

Artemis (Lagrange Points, 550px)

The ARTEMIS spacecraft are currently located at the L1 and L2 Earth-Moon Lagrange points: NASA

 

http://science.nasa.gov/science-news/science-at-nasa/2010/27oct_artemis/

 

Lunar crater “Cabeus” contains more water than the Sahara

October 22, 2010

The New York Times reports on the latest results from the $79 million Lcross mission. Last October, as it neared impact, the Lcross spacecraft released the empty second stage and slowed down slightly so that it could watch the stage’s 5,600-mile-per-hour crash into a 60-mile-wide, 2-mile-deep crater named Cabeus.

 

Debris ejected from the Cabeus lunar crater about 20 seconds after the Lcross impact: image Science / AAAS

 

A series of articles reporting the Lcross results appear in Friday’s issue of the journal Science.

Last November, the team reported that the impact had kicked up at least 26 gallons of water, confirming suspicions of ice in the craters. The new results increase the water estimate to about 40 gallons, and by estimating by amount of dirt excavated by the impact, calculated the concentration of water for the first time. The Sahara sands are 2 to 5 percent water, and the water is tightly bound to the minerals. In the lunar crater, which lies in perpetual darkness, the water is in the form of almost pure ice grains mixed in with the rest of the soil, and is easy to extract. The ice is about 5.6 percent of the mixture, and possibly as high as 8.5 percent of it, Dr. Colaprete principal investigator of NASA’s Lunar Crater Observation and Sensing Satellite —  Lcross – said.

In lunar terms, that is an oasis, surprisingly wet for a place that had long been thought by many planetary scientists to be utterly dry. If astronauts were to visit this crater, they might be able to use eight wheelbarrows of soil to melt 10 to 13 gallons of water. The water, if purified, could be used for drinking, or broken apart into hydrogen and oxygen for rocket fuel — to get home or travel to Mars.

Also surprising was the cornucopia of other elements and molecules that Lcross scooped out of the Cabeus crater, near the Moon’s south pole. Lying in perpetual darkness, the bottom of Cabeus, at minus 370 degrees Fahrenheit, is among the coldest places in the solar system and acts as a “cold trap,” collecting a history of impacts and debris over perhaps a couple of billion years.

“This is quite a reservoir of our cosmic climate,” said Peter H. Schultz, a professor of geological sciences at Brown University and lead author of one of the Science papers. “It reflects things that hit the Moon.”

By analyzing the spectrum of infrared light reflected off the debris plume, Dr. Schultz and his colleagues identified elements like sodium and silver.