This summer, NASA will launch its Laser Communications Relay Demonstration (LCRD), setting the stage for high-speed transmission of data between planets. NASA missions have been using the same technology — radio frequency communications — since the 1950s and the beginning of spaceflight. With the advent of technologies such as 4K video, limits to radio technology have become increasingly evident. To transmit a complete map of Mars, it would take roughly nine weeks with current radio technologies. With lasers, it would take about nine days. Graphic representation of the difference in data rates between radio and laser communications. Courtesy of NASA. Additionally, laser communications systems take up less space and weigh less. This is highly advantageous in the context of space missions, as it can provide more room for scientific instruments and supplies. “LCRD will demonstrate all of the advantages of using laser systems and allow us to learn how to use them best operationally,” said principal investigator David Israel at NASA’s Goddard Space Flight Center. “With this capability further proven, we can start to implement laser communications on more missions, making it a standardized way to send and receive data.” The systems use infrared light to transmit data. Though laser communications are not necessarily faster than radio waves, they are able to transmit more data in one downlink. The reason is that infrared lightwaves are much tighter than radio waves, in terms of how the data are packed. Laser communications terminals in space also use narrower beam widths than radio frequency systems; the results are smaller "footprints" that can minimize interference or improve security by drastically reducing the geographic area where a communications link could be intercepted. However, a laser communications telescope pointing to a ground station must be exact when broadcasting from thousands or millions of miles away. Any deviation, however fractional, can result in the laser missing its target entirely. The LCRD, located in geosynchronous orbit about 22,000 miles above Earth, will be able to support missions in the near-Earth region. LCRD will spend its first two years testing laser communications capabilities with numerous experiments to further refine laser technologies. The first experimental phase will leverage the mission’s ground stations in California and Hawaii, Optical Ground Stations 1 and 2, as simulated users. This enables the evaluation of atmospheric disturbances on lasers and practice switching support from one user to the next. After the experimental phase, LCRD will transition to supporting space missions, sending and receiving data to and from satellites over infrared lasers to demonstrate the benefits of laser communications relay systems. The first in-space user of the system will be NASA’s Integrated LCRD Low-Earth Orbit User Modem and Amplifier Terminal, which is set to launch to the International Space Station in 2022. The terminal will receive high-quality scientific data from experiments and instruments on the space station, which it will then transfer to LCRD at 1.2 Gbit/s. LCRD will transmit the data to ground stations at the same rate. LCRD is set to launch as a payload on a Department of Defense spacecraft June 23, 2021.