Goldstone Solar System Radar, Radio telescope in Mojave Desert, California, US

Goldstone Solar System Radar is a radar astronomy system in the Mojave Desert near Barstow, California. It comprises a 500-kW X-band (8500 MHz) transmitter and a low-noise receiver mounted on the 70-m DSS 14 antenna of the Goldstone Deep Space Communications Complex. It can operate monostatically, transmitting and receiving itself, or bistatically, transmitting while other radio astronomy facilities receive; the 70-m antenna is mainly used for tracking spacecraft of the NASA Deep Space Network.

The Goldstone Solar System Radar operates on the 70-meter DSS 14 antenna at the Goldstone Deep Space Communications Complex, part of NASA's Deep Space Network, which primarily tracks and communicates with spacecraft. The radar is active only a small percentage of the time. It is the only planetary radar in current regular operation, following the 2020 collapse of the Arecibo radar.

The radar installation has influenced scientific research by enabling detailed observations of Mercury, Venus, Mars, asteroids, and moons of Jupiter and Saturn.

The 70-metre DSS 14 antenna is mainly used to track and communicate with spacecraft of the NASA Deep Space Network, so the radar is active only a small percentage of the time. The site lies in the Mojave Desert near Barstow, California, and is an operating research facility rather than a visitor attraction.

The radar revealed through its measurements that Mercury has a liquid core, a major discovery made from remote sensing data. This ability to penetrate distant celestial objects in such detail makes the system an exceptional scientific tool.