NASA scientists beamed an image of Leonardo da Vinci's masterpiece, Mona Lisa, from Earth to the Lunar Reconnaissance Orbiter (LRO), in a bid to demonstrate the first laser communication.
The image traveled nearly 240,000 miles on laser pulses from NASA's Goddard Space Flight Center in Greenbelt, Maryland, to the LRO spacecraft orbiting the moon, thus successfully demonstrating a one-way laser communication with a distant satellite.
"This is the first time anyone has achieved one-way laser communication at planetary distances," Lunar Orbiter Laser Altimeter's (LOLA) principal investigator, David Smith of the Massachusetts Institute of Technology, said in a statement. "In the near future, this type of simple laser communication might serve as a backup for the radio communication that satellites use. In the more distant future, it may allow communication at higher data rates than present radio links can provide."
While satellites that travel beyond Earth's orbit use radio waves for tracking and communication, LRO is the only satellite that is equipped with the laser receiver as well. The image was received by the LOLA instrument on the spacecraft. It was sent into an array of 152 pixels by 200 pixels. Each pixel was transmitted using a laser pulse, and the entire image was transmitted at a data rate of about 300 bits per second.
The instrument reconstructed the image based on the arrival times of the laser pulses from Earth. The image was corrected for the distortions caused when it was transmitted through the Earth's atmosphere. It was then sent back to Earth using the spacecraft's radio telemetry system.
"This path-finding achievement sets the stage for the Lunar Laser Communications Demonstration (LLCD), a high data rate laser-communication demonstrations that will be a central feature of NASA's next moon mission, the Lunar Atmosphere and Dust Environment Explorer (LADEE)," Goddard's Richard Vondrak, the LRO deputy project scientist, said in a statement.
LADEE will be launched to the moon later this year to map the lunar atmosphere and environment, reports Space.com.