Earth Receives Laser Message from 140 Million Miles Away in Deep Space

The asteroid is located in the asteroid belt between the planets Mars and Jupiter. Named Psyche, after the asteroid it is destined for, this robotic explorer had another mission – to test laser communications.

Psyche is equipped with the Deep Space Optical Communications (DSOC) system, which aims to make laser communication possible across vast distances in space, promising much faster connections than current methods. Despite primarily using radio frequency communication, the optical communications technology has proven its capability.

In a remarkable feat, the laser communications demo successfully transmitted engineering data from over 140 million miles away, which is 1.5 times the distance between Earth and the sun, after interfacing with Psyche’s radio frequency transmitter. The DSOC also successfully interfaced with Psyche’s radio transmitter, allowing it to transmit information and engineering data directly from the spacecraft back to Earth.

Meera Srinivasan, the project’s operations lead at NASA’s Jet Propulsion Laboratory (JPL) in Southern California, explained that they downlinked about 10 minutes of duplicated spacecraft data during a pass on April 8. This duplicated data was transmitted via laser communications, while the original Psyche data was sent to ground control using standard radio-frequency communications channels on NASA’s Deep Space Network (DSN).

The objective was to assess if laser communications could perform as effectively, if not better, than traditional methods. NASA’s optical communications demonstration has proven it can transmit test data at a maximum rate of 267 Mbps using the flight laser transceiver’s near-infrared downlink laser, which is similar to broadband internet speeds.

However, because the spacecraft is now much farther away, the data transmission rate is lower. During a test on April 8, the spacecraft successfully transmitted test data at a maximum rate of 25 Mbps, exceeding the project’s goal of proving at least 1 Mbps was achievable at that distance.

Psyche is reportedly stable and healthy as it makes its way towards the Psyche 16 asteroid between Mars and Jupiter.