by Lafe Low

Wireless: Astronauts Call from Aboard International Space Station

Oct 01, 20012 mins

Talk about a long-distance call?astronauts aboard the International Space Station (ISS) orbiting miles above Earth are now phoning home. ISS astronauts use Cisco Systems SoftPhone software running on flight-approved laptops through a voice-over-IP (VoIP) system. “There’s basically a network on board, a network on the ground, and we connect the two,” says Matthew Bordelon, project manager for crew support laptops at the Johnson Space Center in Houston. The first flight test calls were placed from the space shuttle Atlantis in February. The system is being tested for use aboard the station in the future.

ISS astronauts will use the VoIP system to keep in touch with family and friends. The ability to make private calls has psychological benefits for the astronauts, Bordelon says. Up to now, astronauts communicated via radio calls routed through the Mission Control Center (MCC) in Houston?effective for transmitting mission data but a little public for astronauts wishing to exchange greetings with loved ones. Friends and family would either visit the MCC or a teleconference would have to be established for them to make contact.

The only seemingly unavoidable glitch so far is the satellite link delay of a few seconds in voice transmissions. Satellite availability can cause additional delays of up to several minutes. “Most of the time, it’s less than one second,” Bordelon says.

Still, extraterrestrial workers do phone home?ET would be jealous.