The use of invisible lasers in space may sound like science fiction, but it is real.
The upcoming demonstration of NASA’s laser communications relay could revolutionize the way the agency communicates with future missions to the solar system. These lasers could lead to more high-definition videos and photos in space than ever before, according to the agency.
The mission is scheduled to launch as a payload aboard the US Department of Defense’s Space Testing Program 6 on December 5 in Cape Canaveral, Florida. The launch window opened at 4:04 a.m. until 6:04 a.m. ET, and the agency shared live coverage of the launch on NASA TV and its website.
Since 1958, NASA has used radio waves to communicate with astronauts and space missions. As radio waves have a proven track record, space missions are becoming more complex and collecting more data than ever before. Think of infrared lasers as the optical communication version of high-speed internet, as opposed to the frustratingly slow dial-up internet. Laser communications will send data to Earth from an orbit synchronous with the Earth’s rotation, 22,000 miles (35,406 kilometers) above the Earth’s surface at 1.2 gigabits per second, which is like downloading an entire movie in less for a minute.
This will improve data transmission rates 10 to 100 times better than radio waves. Infrared lasers, which are invisible to our eyes, have shorter wavelengths than radio waves, so they can transmit more data simultaneously.
Using the current radio wave system would take nine weeks to send back a complete map of Mars – but lasers could do that in nine days.
Laser Communications Relay Demonstration is NASA’s first end-to-end laser relay system that will send and receive data from space to two ground-based optical stations in Table Mountain, California and Haleakalā, Hawaii. These stations have telescopes that can receive light from lasers and translate it into digital data. Unlike radio antennas, laser communication receivers can be up to 44 times smaller. Because the satellite can send and receive data, it is a true two-way system.
The only disruption to these ground-based laser receivers is atmospheric disturbances, such as clouds and turbulence, which can interfere with laser signals traveling through our atmosphere. The remote locations for the two receivers were chosen in light of this, as both usually have clear weather conditions at high altitudes.
The demonstration acts as a relay satellite, eliminating the need for future missions to have antennas with a direct line of sight to Earth. The satellite could help reduce the size, weight and power requirements for communications on future spacecraft – although this mission is the size of a large mattress. This means that future missions may be less expensive to launch and take place for more scientific tools.
Other emerging missions that could test laser communication capabilities include the Orion Artemis II Optical Communications System, which will allow ultra-high-definition video streaming between NASA and Artemis astronauts venturing to the moon.
And the Psyche mission, which launches in 2022, will reach its asteroid destination in 2026. The mission will study a metal asteroid more than 150 million miles (241 million kilometers) away and test its laser. optical communication in deep space to send data back to earth.