NASA lifts 9 million lbs antenna
Posted: Thu Jul 22, 2010 1:59 pm
Official Annoucement
Article on it
Article on it
But remember, all the politicians think that NASA isn't important!The ubiquitous antenna was all the buzz last week as Apple tried to squelch the latest glitch in its popular iPhone. But those antenna issues have nothing on the renovations NASA is taking on to reinvigorate its 70-meter-wide (230-foot-wide) "Mars antenna."
The antenna, a key cog in NASA's Deep Space Network, needs about $1.25M worth of what NASA calls major, delicate surgery. The revamp calls for lifting the antenna -- about 4 million kilograms (9 million pounds) of finely tuned scientific instruments - to a height of about 5 millimeters (0.2 inches) so workers can replace the steel runner, walls and supporting grout. This is the first time the runner has been replaced on the Mars antenna, NASA said.
The operation on the historic 70-meter-wide (230-foot) antenna, which beamed data and watched missions to deep space for over 40 years, will replace a portion of what's known as the hydrostatic bearing assembly. This assembly enables the antenna to rotate horizontally, NASA stated.
According to NASA, the bearing assembly puts the weight of the antenna on three pads, which glide on a film of oil around a large steel ring. The ring measures about 24 meters (79 feet) in diameter and must be flat to work efficiently. After 44 years of near-constant use, the Mars antenna needed a kind of joint replacement, since the bearing assembly had become uneven, NASA stated.
A flat, stable surface is critical for the Mars antenna to rotate slowly as it tracks spacecraft, NASA said. Three steel pads support the weight of the antenna rotating structure, dish and other communications equipment above the circular steel runner. A film of oil about the thickness of a sheet of paper -- about 0.25 millimeters (0.010 inches) -- is produced by a hydraulic system to float the three pads, NASA stated.
The repair will be done slowly but is expected to be done by early November. During that time, workers will also be replacing the elevation bearings, which let the antenna track up and down from the horizon.
Meanwhile the network will still be able to provide full coverage for deep space missions by using the two other 70-meter antennas at Deep Space complexes near Madrid, Spain, and Canberra, Australia, and arraying several smaller 34-meter (110-foot) antennas together, NASA stated.
While officially known as Deep Space Station 14, the antenna got its Mars moniker from its first mission: tracking NASA's Mariner 4 spacecraft, which had been lost by smaller antennas after its historic flyby of Mars, the space agency stated.