A joint mission between the European Space Agency and Switzerland launched in 2019 December to observe transits of exoplanets around stars down to 12th magnitude. Its aim is to determine the sizes of planets with masses between those of the Earth and Neptune and to investigate their atmospheres. CHEOPS carries a 0.3-m telescope with a high-precision photometer that observes at visible and near-infrared wavelengths (0.4–1.1 µm).

http://sci.esa.int/cheops/ Official ESA website.

http://cheops.unibe.ch Mission home page at the University of Bern.