Laser message from space

Radio communication with the International Space Station occurs at a very low speed, but in the future things may change. On June 5, 2014, a laser modem was launched on the ISS, which repeatedly transmitted a video in HD quality to the Earth with the words “Hello world”.

The laser is clearly visible in the photo.


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If the experiment with the laser system called OPALS (Optical Payload for Lasercomm Science) succeeds, then this will be a significant upgrade for the ISS. Scientists compare this upgrade with the replacement of dialup on DSL: the speed will increase by 10-1000 times, compared to the current one.

True, it is not so simple: to maintain communication, you need to accurately aim the onboard laser at the receiving device in the observatory. This is despite the fact that the station moves at a speed of 7.6 kilometers per second relative to the earth's surface.

To set up an orbital laser, it was first “illuminated” from the Earth. OPALS switched on its 2.5-watt laser and sent a coded response pulse in the direction of the original signal.

The test transmission on June 5 lasted 148 seconds, and the maximum transmission speed reached 50 Mbps. One video was copied in 3.5 seconds, although an ordinary radio modem would transmit it for 10 minutes.

For all 148 seconds of transmission, OPALS successfully held the scope, without rejecting the laser beam by more than 0.01 °.

It is worth noting that the OPALS delivered the space cargo ship Space-X Dragon to the ISS in the spring of 2014.

Private spaceships, laser communications in space - maybe we are already in the future?