National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
Missions
Fobos 2
Missions to Mars
 By Target   By Name   By Decade 
Beyond Our Solar System Our Solar System Sun Mercury Venus Moon Earth Mars Dwarf Planets Dwarf Planets Dwarf Planets Asteroids Comets Jupiter Saturn Uranus Neptune Kuiper Belt
 
 Past 
 Present 
 Future 
 Concepts 
Fobos 2
Fobos 2 Mission to Mars

Mission Type: Lander, Orbiter
Launch Vehicle: 8K82K + Blok D-2 (Proton-K no.356-01 / Blok D-2 no. 1L)
Launch Site: NIIP-5 / launch site 200P
Spacecraft Mass: 6,220 kg
Spacecraft Instruments:
Planetary Studies:
1) VSK videospectrometric system
2) KRFM infrared radiometer/spectrometer
3) ISM infrared spectrometer
4) Thermoscan scanning infrared radiometer
5) GS-14 gamma-emission spectrometer
6) RLK radar system
7) LIMA-D laser mass spectrometric analyzer
8) DION secondary ion mass analyzer
9) ISO optical radiation spectrometer
Plasma studies:
1) MAGMA magnetometer
2) FGMM magnetometer
3) APV-F plasma wave analyzer
4) ASPERA scanning energy-mass spectrometer
5) SOVIKOMS energy-mass charge spectrometer
6) TAUS proton and alpha-particle spectrometer
7) HARP ion and electron spectrometer
8) SLED energetic charged-particle spectrometer
Solar studies:
1) IPHIR solar photometer
2) RF-15 x-ray photometer
3) SUFR ultrasound spectrometer
4) LILAS gamma-burst spectrometer
5) VGS gamma-burst spectrometer
References:
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, by Asif A. Siddiqi, NASA Monographs in Aerospace History No. 24


Fobos 2 had the same mission as its twin Fobos 1, but had an additional payload on board; a 110-kg "hopper" designed to make up to ten 20-m jumps across the Phobos surface to gather surface data on the tiny Martian moon. The orbiter also had a slightly different instrument complement than its predecessor Fobos 1.

Fobos 2 carried out two en route course corrections on 21 July 1988 and 23 January 1989, despite some major problems. One of the two radio transmitters failed when there were spuriously generated commands in one channel of its computer.

At 12:55 UT on 29 January 1989, the spacecraft fired its engine to enter orbit around Mars. Initial orbital parameters were 819 x 81,214 km at 1.5ý inclination. After four further orbital corrections, its trajectory was put on an encounter course with Phobos.

Fobos 2 took high-resolution photos of the moon on 23 February (at a range of 860 km), 28 February (320 km), and 25 March 1989 (191 km).

Release of its lander was scheduled for 4-5 April 1989, but on 27 March, during a regularly planned communications session at 15:58 UT, there was no word from the spacecraft. A weak signal was received between 17:51 and 18:03 UT, but there was no telemetry information. The nature of the signal indicated that the spacecraft had lost all orientation. Future attempts to regain communication were unsuccessful, and the mission was declared lost on 15 April 1989. The most probable cause of failure was simultaneous malfunctions in both channels of the onboard computer (due to insufficiently robust software) that put the spacecraft into an improper tumble.

Editor's Note: This mission profile was adapted from an originally published mission profile in Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, by Asif A. Siddiqi, NASA Monographs in Aerospace History No. 24.


Key Dates
12 Jul 1988:  Launch
15 Apr 1989:  End of Mars Mission
Status: Contact Lost
Fast Facts
Fobos 2 Facts Fobos 2 had a 110-kg "hopper" on board designed to make up to ten 20-m jumps across the Phobos surface to gather surface data on the tiny Martian moon (right).

Both Fobos 1 and Fobos 2 failed to complete their missions.

The most probable cause of Fobos 2's failure was simultaneous malfunctions in both channels of the onboard computer.
Links
Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map   Print This Page
NASA Official: Kristen Erickson
Advisory: Dr. James Green, Director of Planetary Science
Outreach Manager: Alice Wessen
Curator/Editor: Phil Davis
Science Writer: Autumn Burdick
Producer: Greg Baerg
Webmaster: David Martin
> NASA Science Mission Directorate
> Budgets, Strategic Plans and Accountability Reports
> Equal Employment Opportunity Data
   Posted Pursuant to the No Fear Act
> Information-Dissemination Policies and Inventories
> Freedom of Information Act
> Privacy Policy & Important Notices
> Inspector General Hotline
> Office of the Inspector General
> NASA Communications Policy
> USA.gov
> ExpectMore.gov
> NASA Advisory Council
> Open Government at NASA
Last Updated: 10 Dec 2010