NASA receives data via laser at a record distance of 16 million kilometers from Earth
Space probe Psyche has successfully sent data to NASA using a near-infrared laser, 16 million kilometers from Earth. That is forty times the distance from the Earth to the moon. It is the first time that laser communication has been used at such a far distance.
The Psyche spacecraft is equipped with the Deep Space Optical Communications technology to enable laser communications, writes CNN. This system must be tested during the first two years of the Psyche mission. Now, for the first time, data has been received from the DSOC system, 16 million kilometers from Earth.
A DSOC photon detector from NASA (Source)
The laser system should be able to send data back and forth ten to a hundred times faster than with NASA’s traditional radio wave systems. The data is encoded as bits in the photons emitted by the laser. Once these photons reach Earth, they are captured by an array of photon detectors, after which the data is decoded.
Because the near-infrared laser communications system can pack the data into tighter electromagnetic waves than current radio frequency systems, much less energy is required than scattering radio waves. The data is also more difficult to intercept.
Laser communication has already been tested in low Earth orbit and near the moon, but this is the first time it has been used in deep space. There are still some challenges associated with using this system. For example, the positioning of the laser must be properly adjusted in order to send the data successfully. During the initial test, it took 50 seconds to receive the data, but at its furthest distance from Earth, it is expected to take Psyche 20 minutes to send the photons. During that time, both the spacecraft and the Earth have moved, forcing the uplink and downlink lasers to adjust in real time.
Psyche was launched into space in October. The intention is for this space probe to reach the asteroid belt of the same name between Mars and Jupiter, approximately 3.6 billion kilometers from Earth, within six years. If the DSOC test proves successful, NASA expects that this method of data communication will be used in the future on manned missions to communicate with its ground stations.
The space probe Psyche. The laser transceiver with gold cover can be seen at the front. Source: NASA