Wireless internet on the Moon

Ars Technica : Laser-powered communications may one day allow astronauts on the Moon and beyond to enjoy wireless broadband services similar to those used on Earth. Researchers at NASA and MIT have set up four ground-based telescopes that can beam an uplink signal as coded pulses of IR light to a satellite orbiting the Moon. Four laser beams are used instead of just one because of the interference caused by Earth’s atmosphere: By sending multiple beams through different columns of air, the researchers increase the chance that at least one of the beams will reach the receiving station. Last year the team succeeded in transmitting data from Earth to the Moon at 19.44 megabits per second and from the Moon to Earth at 622 megabits per second. They will be presenting their work at the annual CLEO laser technology conference, which this year is being held 8–13 June in San Jose, California.