The Mona Lisa is one of the most famous paintings on Earth. But last week, the painting reached new heights—in outer space!
Using a laser, the space agency NASA beamed a digital image of the Mona Lisa to a human-made satellite orbiting the moon. The image traveled nearly 240,000 miles from NASA’S Goddard Space Flight Center in Greenbelt, Maryland, to the satellite, named the Lunar Reconnaissance Orbiter (LRO).
“This is the first time anyone has achieved one-way laser communication at planetary distances,” says David Smith of the Massachusetts Institute of Technology.
Satellites beyond Earth’s orbit typically use radio waves for tracking and communication. The LRO is the only one that is also tracked by laser.
Because of the success of the Mona Lisaexperiment, Smith says laser communication may someday be used as a backup for satellites’ radio communication. Laser communication could also help speed the delivery of data from outer space and could one day bring live, high-definition video feeds from satellites throughout the solar system.
TO THE MOON AND BACK
The Mona Lisa was painted in the early 1500s by Italian Renaissance artist Leonardo da Vinci. To transmit an image of it to the satellite, NASA scientists divided it into sections measuring 150 by 200 pixels. They then sent the pixellated sections to the satellite using laser pulses. The satellite received the image in pieces and reconstructed it based on the arrival times of the laser pulses. Then it sent the image back to Earth using radio waves.
The image wasn’t perfect when it arrived at the LRO because Earth’s atmosphere caused transmission errors. But scientists were able to fix the errors using the same type of error-correction code found in CDs and DVDs.
The LRO has been orbiting the moon since 2009. NASA’s next moon mission will feature a high-speed laser communication system called the Lunar Laser Communications Demonstration (LLCD). NASA says the Mona Lisa experiment has set the stage for LLCD.
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