Normally, communication from Earth to space and back again is handled by radio frequency (RF) signals. However, as our exploration of space expands, there is an increasing need for communication that is faster, more reliable, and capable of handling more data. Enter NASA's Lunar Laser Communication Demonstration (LLCD), which the agency anticipates will provide evidence that two-way communication between Earth and space is possible by using lasers.
Not only does NASA hope to prove such communication is possible, but it also expects that this technology will be able to extend the range of communication, as well as allow for more data to travel at a faster rate. For example, the agency is hoping to be able to transmit more, higher resolution photos from deep space, as well as 3D video. Laser communication would also be less likely to suffer from interference, another limitation of RF signals. The LLCD's data bandwidth capability is six times that of a standard RF system, and will use a smaller transmitter and less power.
So how will LLCD be tested? The system itself will be launched into the Moon's orbit aboard NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) next week. Once there, LLCD's primary goal is to send insanely huge amounts of data — hundreds of millions of bits per second — from the Moon to several locations on Earth. To get an idea of how much data that is, think of 100 HD televisions channels being sent to the Earth from the Moon at the same time. LADEE will also be receiving a similar amount of data from Earth. NASA hopes to prove that the laser technology will be able to handle more bandwidth for future missions that are further away than Earth's orbit.
LLCD will only be a short experiment, but NASA has already planned for a longer one, the Laser Communications Relay Demonstration (LCRD). That mission will launch in 2017.