Sunday, February 6, 2011

LRO Could Have Given Apollo 14 Crew Another Majestic View

LRO Could Have Given Apollo 14 Crew
Although the Apollo 14 mission to the moon was filled with incredible sights and was completely successful -- it met all its science goals -- the crew experienced a bit of a disappointment at missing the spectacular view from the rim of a 1,000-foot-wide crater. They might have gazed into its depths if they had the high-resolution maps now available from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft.

Pressure was on the Apollo 14 mission, launched January 31, 1971, from the start. The Apollo 13 landing had to be aborted because an oxygen tank explosion crippled the spacecraft as it was on its way to the moon. It was a heroic effort just to return the crew safely to Earth, but the Apollo 14 team knew a second failure would probably result in cancellation of the remaining Apollo missions.

Although nothing as catastrophic as an explosion threatened their mission, the Apollo 14 crew had to improvise their way out of some tense situations. On the way to the moon, the crew had to dock their spacecraft, the Command and Service Module "Kitty Hawk," to the spacecraft that would land on the moon, the Lunar Module "Antares." However, latches that would lock the two spaceships together refused to engage. Kitty Hawk pilot Stuart Roosa tried the docking maneuver six times over more than an hour and a half before the latches activated, linking the spacecraft so that mission commander Alan Shepard and Antares pilot Edgar Mitchell could transfer to the Antares lander. On the way down in Antares, the crew had to overcome computer and radar glitches in the system that was supposed to guide their landing. Even with the balky guidance system, they were able to pilot Antares to within 87 feet from the targeted landing point, at the time the most precise landing for the Apollo missions.

The site, which the crew named the "Fra Mauro Base," was the area to be explored by Apollo 13, a hilly zone about 300 miles from the edge of the 750-mile-wide Mare Imbrium basin formed long ago by the impact of a giant asteroid. The hills of Fra Mauro were believed to be made of rubble blasted from the Imbrium impact, and lunar geologists wanted the crew to collect rocks from the region so they could accurately date when giant impacts like Imbrium occurred on the moon

Similar massive craters exist on Mercury and Mars, so it appears that the entire solar system experienced a chaotic period of "heavy bombardment" from enormous asteroids. Scientists were keen to date this event because it's very likely Earth was hit as well, and impacts of that scale would alter the evolution of life. However, on our world, such ancient craters have been erased by erosion from wind and water, as well as the recycling of the crust from its slow motion as a result of plate tectonics.

Shepard and Mitchell landed Feb. 5, and they performed two moonwalks, technically called "Extravehicular Activities," or EVAs, one on each day of the two days spent on the lunar surface. The first EVA went according to plan, with the deployment of the Apollo Lunar Surface Experiments Package, a suite of instruments that included a seismometer to measure moonquakes and laser reflectors to accurately measure changes in the Earth-moon distance using lasers fired from stations on Earth. During the second EVA, the crew hoped to reach the rim of Cone crater, a more recent impact crater about 1,000 feet wide a little over a mile from the Antares lander.


Post a Comment