https://www.nasa.gov/press-release/nasa-selects-proposals-to-study-volatile-stars-galaxies-cosmic-collisionshttps://www.cnbeta.com/articles/science/964393.htm这四个任务包括两个“小探索者（SMEX）”任务及两个“机会任务（MO）”。
SMEX= 小探測工程 (Small Explorer program )
SMEX => “极紫外恒星的大气物理和进化表征任务（ESCAPE）”和“康普顿光谱仪和成像仪（COSI）”
The Extreme-ultraviolet Stellar Characterization for Atmospheric Physics and Evolution (ESCAPE) Mission
ESCAPE would study nearby stars, watching for rapid, strong ultraviolet flares. It aims to determine how likely such flares are to strip the atmosphere from a rocky planet orbiting the star, affecting conditions for habitability. Principal investigator: Kevin France at the University of Colorado at Boulder.
The Compton Spectrometer and Imager (COSI)
COSI would scan our Milky Way galaxy, measuring gamma rays from radioactive elements produced during stellar explosions to map the recent history of star death and element production. It would also measure polarization, to improve our understanding of how distant energetic cosmic explosions produce gamma rays. Principal investigator: John Tomsick at the University of California, Berkeley.
MO => 引力波紫外线对应物成像仪任务（GUCIM）”和“大面积爆炸式旋光仪（LEAP）
The Gravitational-wave Ultraviolet Counterpart Imager Mission =GUCIM
The Gravitational-wave Ultraviolet Counterpart Imager consists of two independent small satellites, each scanning the sky in a different ultraviolet band. It would detect the light from hot gas in the explosion that follows a burst of gravitational waves caused by merging neutron stars or a neutron star merging with a black hole. Between these events, the mission would map the sky in ultraviolet light, finding other bright objects such as exploding stars.
Principal investigator: Stephen (Brad) Cenko at NASA’s Goddard Space Flight Center in Greenbelt, Maryland
LEAP – A LargE Area burst Polarimeter
Mounted on the International Space Station, LEAP would study the energetic jets launched during the explosive death of a massive star, or the merger of compact objects such as neutron stars. LEAP's measurements of polarization in gamma-ray bursts could distinguish between competing theories for the nature of the jets, which move out at close to the speed of light. LEAP would complement NASA's Imaging X-ray Polarimetry Explorer (IXPE), scheduled to launch in 2021.
Principal investigator: Mark McConnell at the University of New Hampshire in Durham.
除发射成本外，SMEX、MO任务的成本上限分别为1.45亿美元和7500万美元。
两个SMEX任务分别是“极紫外恒星的大气物理和进化表征任务（ESCAPE）”和“康普顿光谱仪和成像仪（COSI）”，每个任务将得到200万美元资助，开展9个月的概念研究。
ESCAPE将研究附近恒星，观察其发出的快速而强烈的紫外线耀斑，确定这些耀斑剥离绕恒星运行岩石行星大气层的几率，而这会影响行星居住环境，任务首席研究员为科罗拉多大学博尔德分校的凯文·弗朗斯。COSI将扫描银河系，测量恒星爆炸过程中产生放射性元素发出的伽玛射线，绘制恒星死亡和元素生成的历史。它还将测量极化，增进我们对遥远高能宇宙爆发如何产生伽玛射线的理解，任务首席研究员是加州大学伯克利分校的约翰·汤姆斯克。
两个MO任务分别是“引力波紫外线对应物成像仪任务（GUCIM）”和“大面积爆炸式旋光仪（LEAP）”，每个提案将获得50万美元资助，开展9个月的概念研究。
GUCIM将由两颗独立小卫星组成，每颗卫星以不同紫外线波段扫描天空，探测两颗中子星或一颗中子星与一个黑洞并和产生引力波爆发中热气体发出的光。该任务将在紫外线下绘制天空图谱，找到其他明亮天体，如爆炸的恒星等，任务首席研究员为戈达德太空飞行中心的斯蒂芬·琴科。LEAP将安装于国际空间站上，研究在巨大恒星死亡或中子星等天体并和期间发出的高能喷流，首席研究员为新罕布什尔大学的马克·麦康奈尔
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