Set your alarms; at 7:30am and 7:34am EDT, the Lunar CRater Observation and Sensing Satellite (LCROSS) and its rocket’s upper stage will impact the moon. The goal of the mission is to search for water ice on the moon. NASA television coverage begins at 6:30am EDT. The target is the Cabeus crater, located about 100km from the South Pole. It can be seen from the Earth, but it is in near perpetual deep shadow.
The Cabeus Crater was named for Niccolo Cabeo (Feb 26, 1586 – June 30, 1650), an Italian Jesuit Philosopher who made notable contributions to mathematics and physics.
Cabeus Crater is large enough that the temperature in the shaded area would remain below 100 K. This means that water ice would remain for billions of years (yes, I said billions with a “b”) without sublimating. Remember, water can go from a solid to a gas, bypassing the liquid stage. This is called “sublimation”. You see it on Earth when a snow pile gets smaller without melting and creating a puddle of water.
LCROSS is attached to a Centaur booster rocket, which will separate as it makes its final approach to the moon. The Centaur rocket will then strike the moon in the Cabeus Crater at about 5,600 mph (9,000 km/h). Upon impact it will eject more that 350 tons of lunar material and create a crater about 66 feet in diameter (20 m). Four seconds after Centaur’s impact, LCROSS will pass through the plume collecting data and relaying it back to Earth. Then LCROSS will impact the crater, ejecting a further 150 tons of material, carving out a crater 46 feet in diameter (14 m).
Scientists on Earth will hopefully be able to determine the presence of water ice in the ejecta from the booster rocket and LCROSS.
Thursday, October 08, 2009
NASA to Bomb the Moon at 7:30 Tomorrow Morning
Why NASA is attacking our closest neighbor: