A communications method that uses pulsed laser beam to send and receive data from faraway locations in space such as the Moon or Mars back to Earth. It is an optical communication technology that uses light propagating in free space (air, outer space, vacuum) to transmit data for telecommunications or computer networks, instead of using physical cables such as optical fiber cable or an optical transmission line.

Compared to radio-frequency communications, which has been in use since the dawn of space age, laser-based communications is able to transmit data 100 times faster, allowing such capabilities as streaming live, high-definition video from faraway planets such as Jupiter and Saturn. Large amounts of data used to take days to transmit can now be accomplished in a matter of minutes. Additionally, laser-based communications can also used to power the backbone for next-generation tracking and data relay satellite (TDRS) network.