SALT LAKE CITY — NASA recently used lasers to send Mona Lisa to the moon.
NASA scientists used the image to test long-distance laser communication systems and gather data about transmissions on the Lunar Reconnaissance Orbiter. According to NASA, LRO is the only satellite orbiting beyond the Earth's orbit to use laser as well as typical radio waves for tracking and communication.
"This is the first time anyone has achieved one-way laser communication at planetary distances," said LOLA's principal investigator, David Smith. "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."
In its two and a half years in space, LOLA has provided global lunar topographic models that will help astronauts make safe landings and create more exploration opportunities.
The image they selected was a digital copy of Leonardo Da Vinci's masterpiece "Mona Lisa." The smiling woman's picture traveled nearly 240,000 miles from a laser ranging station in Greenbelt, Md., to the Lunar Orbiter Laser Altimeter aboard LRO at a data rate of about 300 bits per second.
Scientists divided the digital image into 152 pixels by 200 pixels, converted into shades of gray. Each pixel, assigned a number between zero and 4,095, was transmitted over a separate laser pulse.
The experiment was conducted during a routine tracking of LOLA that utilizes the laser pulses. This experiment simultaneously communicated with the satellite and tracked it.
According to NASA, turbulence in Earth's atmosphere caused transmission errors in the image. Researchers were able to use Reed-Solomon coding — an error-correction system frequently used on CDs and DVDs — to correct the image and gather statistics on the signal fluctuations due to Earth's atmosphere.
"This pathfinding achievement sets the stage for the Lunar Laser Communications Demonstration, 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)," said Richard Vondrak, the LRO deputy project scientist.