Cool Companions on Ultrawide Orbits

The COol Companions ON Ultrawide orbiTS (COCONUTS) program is a large-scale survey for wide-orbit planetary and substellar companions considered the first survey of this type of celestial bodies.^[1] In 2021, the team announced COCONUTS-2b, the closest exoplanet directly imaged ever.^[2] The program is a dedicated large-scale search for wide-orbit giant planets and brown dwarf companions, targeting a sample of 300,000 stars. By using multi-wavelength photometry and multi-epoch astrometry, astronomers are able to assess the candidates' companionship and ultracool nature.^[3]

COCONUTS-2b

List of discoveries

Name	companion class	mass (MJ)	orbital separation (au)	host star	star class	host star mass (M☉)	discovery year	reference
COCONUTS-1B	brown dwarf	15.4 or 69.3	1280	PSO J058.9855+45.4184	old white dwarf	0.548	2020	[4]
COCONUTS-2b	exoplanet	6.3	6471	L 34-26	young M-dwarf	0.37	2021	[5]
COCONUTS-3B	brown dwarf	39	1891	UCAC4 374-046899	young M-dwarf	0.123	2022	[6]

See also

• List of exoplanet search projects