About this world
AT2021ueyL b is a gas giant orbiting AT2021ueyL, a cool red dwarf (type MV) 3.39 thousand light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass) and holds 1.3 Jupiter masses. It completes an orbit every 11.4 years at 4 AU from its star.
At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2025 by microlensing with Multiple Observatories. A foreground star's gravity magnifies a background star; a planet adds a blip.