ON THE MOON THE GRAIL SHIPS ARRIVED

It is the mission GRAIL (Gravity Recovery and Interior Laboratory), which aquaculture the crust and the core mole to discern its structure."Our team is not going to have a traditional New Year celebration, but I hope to see our two ships safely in lunar orbit, something that gives us all the excitement and the feeling of euphoria that any necesiatría in a work of this kind "said David Lehman, GRAIL project manager at the Jet Propulsion Laboratory (JPL) in Pasadena, California.

The distance from Earth to the Moon is about 402,336 km. At NASA's Apollo missions took them about three days to travel to the moon. Launched from Cape Canaveral on 10 September, the ships GRAIL (Grail in Castilian) have traveled more than 4 million miles to get there.

This long history has given the mission planners and controllers more time to assess the state of the ship. The road also allowed a vital component among the instruments of the spacecraft - the Ultra Stable Oscillator -, could be fed continuously for several months. This allows you to reach a stable operating temperature before you begin to make scientific measurements in lunar orbit.

"This mission will rewrite textbooks on the evolution of the moon," said Maria Sober, senior researcher at the Institute GRAIL of Technology (MIT). "Our two ships are working so well for the journey we have made ​​full proof of our science instruments and confirmed the performance to meet our goals."

In its final approach of the moon orbiters move it from the south, flying about on the lunar south pole. The inserts in lunar orbit are separated by about 25 hours.

During the following weeks, the team will execute maneuvers GRAIL on each ship to reduce its orbital period of 11.5 hours to just less than two hours. At the beginning of the science phase in March, both will be near the poles, with a nearly circular orbit with an altitude of 55 kilometers.

When data collection begins, the ships sent radio signals to each other to accurately measure the distance between them. While flying over the areas of major and minor, caused by both visible features such as mountains and craters hidden by the masses as under the lunar surface will move slightly. An instrument aboard each spacecraft will measure the changes in relative velocity very accurately, and scientists translate this information into a high-resolution map of the Moon's gravitational field.