NASA Plans to Send High-Definition Video of Mars to Earth With Lasers
In 2022, NASA will launch the Psyche mission, carrying sophisticated communication technology
Pictures from space have allowed scientists to examine and search for clues about other planets and let space enthusiasts get a rare view beyond Earth.
Now, NASA wants to take that experience to a new level by transmitting high-definition video from places like Mars to Earth using laser beams.
As Joel Palca reports for NPR’s All Things Considered, the agency is planning to launch a probe that will allow data from future missions there to be transmitted via video.
Called Deep Space Optical Communications (DSOC), the technology that can beam high-def video to Earth from deep space as it travels aboard the Psyche mission, set to launch in 2022.
Psyche won't go directly to Mars; rather, it will enter and leave the gravitational field of Mars on the way to the aestroid the mission is named after. Along the way, it will be able to "transmit the clearest, quickest information ever obtained from an expedition into the solar system," according to NASA.
On Earth, Alexander Graham Bell, the inventor of the telephone, also built a machine that used light from the sun to transmit sound, Palca writes, the precursor to today's fiber-optic cables. In both cases, data is converted into pulses of light, then re-converted into data—photos, music, or cat videos—on the receiving end. The DSOC works much the same way, but uses pulsed laser beams.
The probe won’t be the first time NASA uses laser light to beam data from space. In 2013, the agency did so as part of its Lunar Laser Communication Demonstration project. As Smithsonian.com reported, this proved it could transmit real-time data and 3-D high-definition video from space.
But doing so from Mars will be a new challenge. The red planet is much further away from Earth compared to the moon — about 140 million miles away, to be exact.
"The biggest challenges, by far, have to do with distance," Kevin Kelly, CEO of LGS Innovations in Herndon, Va., which is helping build DSOC, tells Palca.
This makes pointing the laser and getting a signal that’s strong enough to transmit the video a problem, Kelly says.
As Palca explains, a laser beam might take 20 minutes to travel between Earth and Mars. By the time the beam reaches where Earth was, the planet has moved. Instead, scientists have to predict where the Earth will be when a signal arrives.
On Earth, the Hale telescope, a 200-inch telescope located at the Palomar Observatory in California, will capture the light, which will then go into a detector that can measure even the faintest of signals.
Elsewhere, scientists are also working on using laser communication closer to home. Palca reports MIT's Lincoln Laboratory is building a mini optical system to send to low Earth orbit that will transmit data at 200 gigabits per second.