NASA readies its first laser communications system for launch
We’ve already seen NASA use its experimental laser communications system to beam an image of the Mona Lisa to the moon. Now, NASA has mounted a portable version of the system onto a droid it plans to blast into space.
NASA just finished testing and installed its first high-data-rate laser communications system for the moon-orbiting Lunar Atmosphere and Dust Environment Explorer (LADEE). When the probe launches later this year, the mission will mark the first time NASA has moved away from a radio transmission-based system to a full-on laser data link.
The laser communication system, called the Lunar Laser Communication Demonstration (LLCD), uses an infrared laser that transmits high-speed in the same way the fiber-optic cables in your house do. The scientists expect that the increased data throughput will allow them to control the satellite in real-time and download 3D high-definition video—whereas the traditional S-band communications would take 639 hours to download an average-length HD movie.
Of course there are some inherent problems with transmitting light from space to Earth. For starters, the LLCD will have to point a laser beam to ground stations located in Mexico, California or Spain from a distance of approximately 238,900 miles (384,472 kilometers) while moving through space.
"This pointing challenge is the equivalent of a golfer hitting a ‘hole-in-one' from a distance of almost five miles," said Donald Cornwell, LLCD mission manager, in a release. "Developers at the Massachusetts Institute of Technology's Lincoln Laboratory have designed a sophisticated system to cancel out the slightest spacecraft vibrations. This is in addition to dealing with other challenges of pointing and tracking the system from such a distance.”
If all goes well with the LLCD, NASA plans to use the mission as a pathfinder for its upcoming Laser Communication Relay Demonstration which the agency hopes to launch in 2017.