火衛一計畫

火衛一計畫 () 是一項蘇聯探測計畫，該計畫由兩顆無人空間探測器組成，以探測火星及其的衛星(火衛一和火衛二)。火衛一1號和火衛一2號分別在1988年7月7日和1988年7月12日使用質子K型運載火箭發射。

火衛一1號在前往火星的途中失聯。 火衛一2號 成功進入火星軌道，但在著陸器着陸之前失去聯繫 火衛一1號和火衛一2號使用了全新的探測器設計，繼承了1975 年至 1985 年期間金星計畫使用的4MV型探測器，以及維加1號和維加2號哈雷彗星任務中使用的5VK型探測器。每個探測器的質量為2600公斤 (安裝軌道插入硬體後質量為 6220 公斤).

這次計畫除了蘇聯之外，還與其他14個國家合作，其中包括瑞典、瑞士、奧地利、法國、西德和美國等國。(美國貢獻了其深空網路來追蹤這對探測器).
目的

The objectives of the Phobos missions were to:

 conduct studies of the interplanetary environment;
 perform observations of the Sun;
 characterize the plasma environment in the Martian vicinity;
 conduct surface and atmospheric studies of Mars; and,
 study the surface composition of the Martian satellite Phobos.

設計

The main section of the spacecraft consisted of a pressurized toroidal electronics section, surrounding a modular cylindrical experiment section. Below these were mounted four spherical tanks (the Fregat stage) containing hydrazine for attitude control and, after the main propulsion module was to be jettisoned, orbit adjustment. A total of 28 thrusters (twenty-four 50 N thrusters and four 10 N thrusters) were mounted on the spherical tanks, with additional thrusters mounted on the spacecraft body and solar panels. Attitude was maintained through the use of a three-axis control system, with pointing maintained with Sun and star sensors.

火衛一1號

火衛一1號一開始運作正常，但在前往火星幾週後，原定於1988年9月2日的聯繫卻失敗。控制人員與探測器失聯，事後被查明是因為在1988年8月29日或30日上傳的軟體發生故障，姿態推進器停止運作。導致太陽能板無法再對準太陽，從而耗盡了電池電量。

Software instructions to turn off the probe's attitude control, normally a fatal operation, were part of a routine used when testing the spacecraft on the ground.  Normally this routine would be removed before launch.  However, the software was coded in PROMs, and so removing the test code would have required removing and replacing the entire computer.  Because of time pressure from the impending launch, engineers decided to leave the command sequence in, though it should never be used.  However, a single-character error in constructing an upload sequence resulted in the command executing, with subsequent loss of the spacecraft.

火衛一2號

火衛一2號在1988年7月12日使用質子K型運載火箭發射，並於1989年1月29日進入火星軌道。1989年1月29日，火衛一2號巡航階段和火星軌道插入階段成功，並收集了有關太陽、行星際介質、火星和火衛一的數據。火衛一2號號探測了火星表面和大氣層及傳回了37張分辨率高達 40 米的火衛一圖像，火衛一2號在準備著陸器着陸之前失去聯繫。
系統和科學儀器

Phobos probes carried several instruments:  solar x-ray and ultraviolet telescopes, a neutron spectrometer and the Grunt radar experiment designed to study the surface relief of Phobos.
The lander had an x-ray/alpha spectrometer to provide information on the chemical element composition of the surface of Phobos, a seismometer to determine the internal structure of Phobos, and the "Razrez" penetrator with temperature sensors and an accelerometer for testing the physical and mechanical properties of the surface.

The Phobos 2 infrared spectrometer (ISM) obtained 45000 spectra in the near infrared (from 0.75 to 3.2 μm) in the equatorial areas of Mars, with a spatial resolution ranging from 7 to 25 km, and 400 spectra of Phobos at 700 m resolution. These observations made it possible to retrieve the first mineralogical maps of the planet and its satellite, and to study the atmosphere of Mars. ISM was developed at IAS and DESPA (Paris Observatory) with support from CNES.

List of instruments:
 "VSK" TV imaging system
 PROP-F "hopping" lander. Only carried by Phobos 2.
ARS-FP automatic X-ray fluorescence spectrometer
ferroprobe magnetometer
Kappameter magnetic permeability / susceptibility sensor
gravimeter
temperature sensors
BISIN conductometer / tiltmeter
mechanical sensors (penetrometer, UIU accelerometer, sensors on hopping mechanism)
"DAS" (long-lived autonomous station) lander
TV camera
ALPHA-X Alpha-Proton-X-Ray Spectrometer
LIBRATION Sun sensor (also known as STENOPEE)
Seismometer
RAZREZ anchor penetrometer
Celestial mechanics experiment
 "ISM" thermal infrared spectrometer/radiometer - 1–2 km resolution
 near-infrared imaging spectrometer
 thermal imaging camera; magnetometers
 gamma-ray spectrometers
 X-ray telescope
 radiation detectors
 radar and laser altimeters
 Lima-D laser experiment - designed to vaporise material from the Phobos surface for chemical analysis by a mass spectrometer
 Automatic Space Plasma Experiment with Rotating Analyzer (ASPERA), an electron spectrometer and ion mass analyser from the Swedish Institute of Space Physics.
 "Grunt" imaging radar - Only carried by Phobos 1

參見
 火星探測
 火星探測任務列表
 太空探索

參考資料

 Articles in Nature 341 (1989) pages 581 - 619
Phobos Project Information (NASA NSSDC) 
Fobos 1F
ISM - Phobos-2 archive 
The Airport Terminal - also known as Mariner 9 #4209-75 

外部連結
 High quality processed images from the Phobos 2 mission
 Phobos mission images from the Space Research Institute (IKI) 
 Raw image data from the Phobos 2 ISM infrared instrument 
 What we are searching for on Phobos  - an article on the Phobos program at the Web site of the Russian Space Agency 
 Another site with processed images from the Soviet Phobos 2 mission

Category:火星探測器
Category:1988年蘇聯
Category:1988年航天

Category:火衛一