NASA successfully beamed a high-definition video from the International Space Station to Earth last Thursday using a new laser communications instrument.
The 175-megabit video transmission of “Hello, World!” was the first of its kind for the Optical Payload for Lasercomm Science (OPALS), a technology demonstration that allows NASA to test optical communications—also known as lasercomm—as a means of communicating with future spacecraft beyond low-Earth orbit.
“It’s incredible to see this magnificent beam of light arriving from our tiny payload on the space station,” Matt Abrahamson, OPALS mission manager at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., said.
The technology uses focused laser energy to achieve data rates 10 to 1,000 times higher than current space communications, which rely on federally-regulated radio frequencies. Scientists believe it could better meet the needs of advanced scientific instruments, which require increasingly higher communication rates to transmit their gathered data back to Earth.
“We look forward to experimenting with OPALS over the coming months in hopes that our findings will lead to optical communications capabilities for future deep space exploration missions,” Abrahamson said.
The ISS orbits Earth at approximately 17,000 mph, requiring extremely precise targeting for successful transmission of data. The process can be likened to a person directing a laser pointer at the end of a human hair 30 feet away and keeping it there while walking.
To achieve this precision during last week’s demonstration, OPALS locked onto a ground beacon emitted by the Optical Communications Telescope Laboratory ground station at the Table Mountain Observatory in Wrightwood, Calif. and began to modulate the beam from its 2.5-Watt, 1,550-nanometer laser to transmit the video.
According to NASA officials, it took OPALS 3.5 seconds to transmit a single copy of the “Hello, World!” video message, which would have taken more than 10 minutes using traditional downlink methods. The message was sent several times during the course of the 148-second transmission, during which a maximum data rate of 50 megabits per second was achieved.
The OPALS instrument was built at JPL as part of the Phaeton hands-on training program and is slated to run for a prime mission of 90 days. During the mission, NASA also will train personnel in optical communication systems operations.
The OPALS Project Office is based at JPL, a division of the California Institute of Technology in Pasadena.
