About this world
OGLE-2011-BLG-0173L b is a Neptune-like planet orbiting OGLE-2011-BLG-0173L, a star 19.9 thousand light-years from Earth. It is about 0.8 times the size of Jupiter (its size estimated from its mass) and holds 0.19 Jupiter masses.
At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2018 by microlensing with OGLE. A foreground star's gravity magnifies a background star; a planet adds a blip.