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Phobos Program

A Phobos spacecraft

A Phobos spacecraft. (Credit: Soviet Space Program)

The Soviet Phobos program consisted of two unmanned probes sent to study Mars and its two moons, Phobos and Deimos.


Country (primary): Soviet Union

Primary Science

The primary mission of the Phobos probes was to study Mars and its two moons, Phobos and Deimos. In addition to instrumentation to explore the Martian satellites, the Phobos probes also carried instruments to study the Sun, Mars, the interplanetary medium, and gamma-ray burst sources. Unfortunately, Phobos 1 was lost enroute to Mars after a faulty command sequence was sent that caused the spacecraft to shutdown. Phobos 2 arrived at Mars in January 1989, but was lost while maneuvering to encounter Phobos in March 1989.

High Energy Science

Each Phobos probe carried 25 instruments, a few of which were high-energy detectors. These included a low-energy and a high-energy gamma-ray burst detector, an X-ray spectrometer and a gamma-rya emission spectrometer.

Science Highlights

  • Observed a number of gamma-ray bursts

Links to more information

Phobos 1

Lifetime: July 1988 - September 1998

Phobos 2

Lifetime: July 1988 - March 1989