Space Laser Communication

- Overview

Space laser communication, also known as optical or free-space communications, uses modulated laser beams to send and receive information wirelessly. 

Laser communication is faster than radio frequency systems because it uses data encoded onto laser light, which has shorter wavelengths than radio. It can transfer data at speeds of up to several gigabits per second, which is 100 times faster than the fastest internet speeds in most cities.  

Laser communication has many applications, including inter-satellite communications and satellite-to-ground connectivity. For example, satellites can send information to Earth via laser signals. 

Some disadvantages of laser communication include: 

• Cloud cover and atmosphere can distort data being sent
• If cloud cover is really heavy, no data can be recovered
• Transmitting in free space also introduces interference from background radiation, most notably the Sun

- NASA's Space Station Laser Communication Terminal

NASA has successfully used lasers to transmit data between Earth and two spacecrafts, completing a groundbreaking experiment that could aid future missions to other worlds. 

The National Aeronautics and Space Administration (NASA) has completed the first laser link for an on-orbit laser relay system, marking a major advancement in space communications technology. 

On December 5, 2023, two-way laser communications between laser terminals in different orbits were successfully demonstrated, which can lay the foundation for faster communications between the earth and the moon and even beyond. 

NASA successfully achieved the first two-way laser link with an on-orbit laser relay system on December 5, 2023. The experiment, which took several years, showed that two-way laser communications could be used between orbits. 

The payload of the experiment, the Integrated LCRD Low Earth Orbit User Data Machine and Amplifier Terminal (ILLUMA-T), was delivered to the International Space Station (ISS) on November 9, 2023. The experiment could speed up communications between Earth and the moon and beyond. 

The experiment took several years to complete. The Integrated LCRD Low Earth Orbit User Data Machine and Amplifier Terminal (ILLUMA-T) payload was delivered to the International Space Station (ISS) aboard a SpaceX Falcon 9 rocket on November 9 as part of NASA's 29th Commercial Resupply Services mission.