對宇宙間最高能粒子進行探測是一項技術(shù)挑戰(zhàn)。把儀器設(shè)備安置在高空氣球和衛(wèi)星上帶上天空進行的天體物理觀測實驗更加困難。如果是為了探測來自恒星和星系的X射線或γ射線輻射，這項技術(shù)就有很大的意義。地球大氣是這些種輻射的強吸收物，氣球或衛(wèi)星能使觀測在大氣以上進行。另一方面，如果打算用這種辦法捕捉超高能宇宙射線，就必須有極大的耐心。能量高于1019eV的宇宙射線粒子，平均每年在1平方公里的面積上只落下一顆。換成空間觀測，利用面積為1平方米的典型衛(wèi)星探測器攔截的話，等待100萬年才有可能探測到1顆這類宇宙射線的粒子!
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ACE [Advanced Composition Explorer] Mission mainly for solar particles; launched in August 1997.
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AGILE [Astro-rivelatore Gamma a Immagini LEggero] X-ray/gamma ray mission to be launched in October 2006.
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AMS [Alpha Magnetic Spectrometer] Detector to be flown on the International Space Station
利用強磁場和精密探測器來探測宇宙空間的反物質(zhì)和暗物質(zhì)，探索和研究宇宙物理學、基本粒子物理學和宇宙演化學的一些重大和疑難問題的阿爾法（α）磁譜儀（Alpha Magneitic Spectrom-eter，簡稱AMS）的研制工作正在進行。AMS是人類送入宇宙空間的第一個大型磁譜儀，這是美籍華裔物理學家丁肇中教授提出并領(lǐng)導的大型國際合作科學研究項目，由美國和中國等10多個國家和地區(qū)的37個科研機構(gòu)參加科研工作。
AMS由一個直徑約1.2米、高0.8米、重量約為1.85噸的圓環(huán)形永磁體產(chǎn)生均勻的平行磁場，磁束密度約為0.15特斯拉。圓環(huán)內(nèi)安裝6層硅微調(diào)探測器，用來記錄帶電宇宙射線粒子的運動軌跡。一個帶正電荷的粒子在穿過磁場時，其運動方向?qū)⑴c帶負電的相反。
根據(jù)每層記錄下來的帶電粒子穿過的軌跡，可以推算出粒子的偏轉(zhuǎn)方向及帶電荷的大小。帶電荷量愈大，在穿過每層硅微調(diào)探測器時能量損失愈快。具有較大動量的粒子在穿過探測器時偏轉(zhuǎn)的角度較小，從而可以估計出粒子的質(zhì)量。磁譜儀的上、下兩層還裝有閃爍體，當粒子穿過時會發(fā)出亮點，其亮度與粒子穿過時的能量成正比。通過上、下兩層光點亮度及穿過瞬間的比較，可以得出粒子能量的損失大小以及粒子穿過所需的時間。反物質(zhì)、暗物質(zhì)在磁場中運動時會表現(xiàn)出不同的特點，因而可以探測出來。1998年6月AMS搭載美國"發(fā)現(xiàn)號"航天飛機成功地進行了首次飛行，進行了約10天的試驗性探測，取得了許多重大物理成果。計劃于2008年升空進入由美、
俄、西歐、日本和加拿大等國聯(lián)合研究的“國際空間站”進行長達3―5年的數(shù)據(jù)采集工作。（左圖為“發(fā)現(xiàn)號”航天飛機上的AMS）
中國在這項重要的研究和應(yīng)用中也作出了重要的貢獻。高能所等單位承擔大型永磁體系統(tǒng)的設(shè)計、研制、測試和空間環(huán)境模擬實驗。（右圖為AMS01永磁體系統(tǒng)在北京進行震動實驗）
AMS二期工程中高能所參加了最重的子探測器--電磁量能器AMS-02的研制。AMS-02設(shè)計載荷要求最高、最苛刻，高能所研制的初樣成功通過了空間環(huán)境模擬試驗，達到了美國NASA的技術(shù)要求，并依據(jù)所建立的有限元模型對AMS-02作了減重，對飛行件設(shè)計方案作了相應(yīng)的修正。AMS-02飛行件主體總裝和空間環(huán)境模擬試驗于2004年完成，通過了NASA專家的嚴格審查。中國在研制過程中掌握了數(shù)項國內(nèi)以往沒有成熟經(jīng)驗的先進試驗技術(shù)及模擬計算修正技術(shù)，獲得了很高的國際顯示度。
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ASCA [Advanced Satellite for Cosmology and Astrophysics] (X-ray mission but with some cosmic-ray relevant results, see also here). Observations ended July 14, 2000.
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BeppoSAX [Satellite per Astronomia X] (operational May 1996 - April 2002)
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Chandra X-ray satellite
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CGRO [Compton Gamma Ray Observatory] (mission terminated) with the four experiments:
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BATSE [Burst And Transient Source Experiment]
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OSSE [Oriented Scintillation Spectrometer Experiment]
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Comptel [imaging Compton telescope] (also here)
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EGRET [Energetic Gamma Ray Experiment Telescope]
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Geotail (measures the Earth's magnetotail)
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GLAST [Gamma ray Large Area Space Telescope] (to be launched in Oct. 2007, see also NASA page)
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GRANAT gamma-ray satellite with several experiments (SIGMA, WATCH and others) was turned off November 27, 1998
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HETE [High-Energy Transient Experiment] (launch failed on 4 Nov. 1996) has a follow-up:
HETE-2 (launched October 9, 2000).
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IMP-8 (Interplanetary Monitoring Platform)
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INTEGRAL [INTErnational Gamma-Ray Astrophysics Laboratory] (launched October 17, 2002)
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NINA [New Instrument for Nuclear Analysis], a mission for low energy cosmic rays.
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PAMELA (magnet spectrometer, launched June 15, 2006). See also here.
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Polar (examines the Earth's magnetosphere and ionosphere)
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Rosat X-ray satellite (ended February 12, 1999)
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RXTE [Rossi X-ray Timing Explorer]
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SAMPEX [Solar Anomalous Magnetospheric Particle Explorer]
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Spectrum-X-Gamma satellite is a future mission (see also here and here)
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Suzaku X-ray satellite (Astro-E2 mission, see also this NASA page)
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SWIFT (gamma ray burst mission, launched November 20, 2004)
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Ulysses (explores interplanetary space at high solar latitudes)
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Voyager (two spacecrafts heading towards interstellar space)
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WIND (explores solar wind and plasma processes near the earth as well as gamma-ray bursts)
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XMM-Newton [X-ray Multi-mirror Mission] (see also pages at GSFC)
Some missions/experiments proposed or under development:
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ACCESS [Advanced Cosmic ray Composition Experiment for the Space Station] (see also pages at U. of Maryland)
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AGILE [Astro-rivelatore Gamma a Immagini LEggero] (a light-weight gamma-ray imager, see also here)
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Andromeda (a coded-aperture gamma-ray telescope)
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BLAST [Burst Locations with an Arc Second Telescope]
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EUSO [Extreme Universe Space Observatory ] (see also under fluorescence experiments)
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MEGA [Medium Energy Gamma-ray Astronomy]
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OWL [Orbiting Wide-angle Light-collectors] (see also under fluorescence experiments)
For a comprehensive list of high-energy astrophysics missions see here. For a list of gamma-ray missions see also this page.
