DSN's Experimental Hybrid Antenna Tracks DSOC's Laser Downlink

Deep Space Station 13 (DSS-13) at NASA's Goldstone Deep Space Communications Complex near Barstow, California – part of the agency's Deep Space Network – is a 34-meter (112-foot) experimental antenna that has been retrofitted with an optical terminal (the boxy instrument below the center of the antenna's dish).

Since November 2023, DSS-13 has been tracking the downlink laser of the Deep Space Optical Communications (DSOC) experiment that is aboard NASA's Psyche mission, which launched on Oct. 13, 2023. In a first, the antenna also synchronously received radio-frequency signals from the spacecraft as it travels through deep space on its way to investigate the metal-rich asteroid Psyche.

Figure A is a close-up of the optical terminal, which consists of seven segmented hexagonal mirrors that mimic the light-collecting aperture of a 3.3-foot (1-meter) telescope. As the laser photons arrive at the antenna, each mirror reflects the photons and precisely redirects them into a high-exposure camera attached to the antenna's subreflector, which is suspended above the center of the dish.

The laser signal collected by the camera is then transmitted through optical fiber that feeds into a cryogenically cooled semiconducting nanowire single photon detector. Designed and built by JPL's Microdevices Laboratory, the detector is identical to the one used at Caltech's Palomar Observatory, in San Diego County, California, that acts as DSOC's downlink ground station.

Goldstone is one of three complexes that comprise NASA's Deep Space Network, which provides radio communications for all of the agency's interplanetary spacecraft and is also utilized for radio astronomy and radar observations of the solar system and the universe. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the DSN for the agency.

More information about the DSN is at: http://deepspace.jpl.nasa.gov/.