About this world
KMT-2019-BLG-0253L b is a sub-Neptune orbiting KMT-2019-BLG-0253L, a star 16 thousand light-years from Earth. It is about 3 times the size of Earth (its size estimated from its mass) and holds 9.2 Earth masses.
At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2022 by microlensing with KMTNet. A foreground star's gravity magnifies a background star; a planet adds a blip.