The Space Infrared Telescope for Cosmology and Astrophysics (SPICA), was a proposed infrared space telescope, follow-on to the successful Akari space observatory. It was a collaboration between European and Japanese scientists, which was selected in May 2018 by the European Space Agency (ESA) as a finalist for the next Medium class Mission 5 of the Cosmic Vision programme, to launch in 2032. At the time the other two finalists were THESEUS and EnVision, with the latter that was eventually selected for further development. SPICA would have improved on the spectral line sensitivity of previous missions, the Spitzer and Herschel space telescopes, between 30 and 230 µm by a factor of 50—100. A final decision was expected in 2021, but in October 2020, it was announced that SPICA was no longer being considered as a candidate for the M5 mission. History In Japan, SPICA was first proposed in 2007, initially called HII-L2 after the launch vehicle and orbit, as a large Strategic L-class mission, and in Europe it was proposed to ESA's Cosmic Vision programme (M1 and M2), but an internal review at ESA at the end of 2009 suggested that the technology readiness for the mission was not adequate. In May 2018, it was selected as one of three finalists for the Cosmic Vision Medium Class Mission 5 (M5) for a proposed launch date of 2032. Within ESA, SPICA was part of the Medium Class-5 (M5) mission competition, with a cost cap of 550M Euros. It stopped being a candidate for M5 in October 2020 due to financial constraints. Overview The concept was a collaboration between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA). If funded, the telescope would have been launched on JAXA's H3 launch vehicle. The Ritchey–Chrétien telescope's 2.5-metre mirror (similar in size to the mirror of the Herschel Space Observatory) would have been made of silicon carbide, possibly by ESA given their experience with the Herschel telescope. The main mission of the spacecraft would have been the study of star and planetary formation. It would have been able to detect stellar nurseries in galaxies, protoplanetary discs around young stars, and exoplanets, helped by its own coronograph for the latter two types of objects. Description The observatory would have featured a far-infrared spectrometer and was proposed to be deployed in a halo orbit around the L2 point. The design featured V-groove radiators and mechanical