The Earth received a laser message from a distance of 16 million kilometers

Experimental Deep Space Optical Communications (DSOC) system navigating the expanses of space on a NASA ship Psyche, for the first time transmitted a message using a laser to Earth from a point far beyond the Moon. Scientists considerthat this achievement could change the way spacecraft communicate.

DSOC uses advanced near-infrared lasers. The system transmitted a test encoded message to Earth from a distance of about 16 million kilometers, which is about 40 times farther than the Moon is from Earth. The signal arrived at the Hale Telescope at the Palomar Observatory at the California Institute of Technology.

In a DSOC laser beam, the photons move in the same direction at the same wavelength. When targeted to a signal receiver, the system can transmit enormous amounts of data at unprecedented speeds.

Such communications have been used before to send messages from low-Earth orbit, but this is the first time it has been used at such a great distance. Typically, radio waves are used to connect with missions further than the Moon. Now, with a laser, the speed of sending data from space can increase by 10–100 times.

This technology will allow future missions to use scientific instruments at much higher resolution, as well as will provide faster communication during flights in deep space - for example, live video broadcasts from the surface Mars.

But such a channel has its own difficulties. The further away the signal sender is, the more difficult it becomes to set up the connection, since high precision is required to aim the laser beam. In addition, as the distance increases, the photon signal becomes weaker and takes longer to reach its destination, which will ultimately lead to delays in communication with the transmitter.

During the Psyche test, the photons took about 50 seconds to reach Earth. By the time the mission reaches its destination, the system will need about 20 minutes. During this time, the position of the planet and the spacecraft will change, so DSOC will have to adapt ahead of the curve. How this will succeed, and whether it will succeed at all, we will find out closer to the end of the mission - in 2029. Although there will still be a lot of tests before that time.