NASA has given the green light to PRIMA, the first mission in its new Probe Explorers line, with a launch target of 2033. The observatory will study the universe in far-infrared light, a range that has been only partially explored by earlier missions like Spitzer and Webb. PRIMA's $1.2 billion cost cap (excluding launch) places it between NASA's smaller Explorer missions and flagship observatories such as the $4.3 billion Roman Space Telescope.
To keep costs and schedule under control, PRIMA will reuse a spare cryocooler left over from the James Webb Space Telescope, modifying it to use helium-3 as the cooling fluid. Its detectors will be chilled to 100 milliKelvin, potentially making its optics the coldest ever sent into space. The mission will operate from the Sun-Earth L2 point, using a 1.8-meter mirror to peer deeper into far-infrared wavelengths than any previous NASA infrared observatory.
Scientists leading the mission say PRIMA will investigate the origins of planets and their atmospheres, the coevolution of galaxies and black holes, and how water on Earth came to be. NASA officials described the mission as part of a pipeline that will keep launching "premier-class" observatories into the next decade.
PRIMA became the sole finalist after NASA disqualified the competing X-ray mission AXIS, whose lead scientist blamed disruptions and mismanagement at Goddard Space Flight Center. PRIMA will be led by NASA's Jet Propulsion Laboratory, which is itself facing layoffs and few missions in development. The article is based on a single source, so there are no differing accounts to compare.