1.4 KiB
| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| WASP-21 | 1/1 | https://en.wikipedia.org/wiki/WASP-21 | reference | science, encyclopedia | 2026-05-05T13:28:34.487246+00:00 | kb-cron |
WASP-21, also named Tangra, is a G-type star (spectral type G3V) that has reached the end of its main sequence lifetime. It lies approximately 834 light-years away, in the constellation of Pegasus. The star is relatively metal-poor, having 40% of heavy elements compared to the Sun. Kinematically, WASP-21 belongs to the thick disk of the Milky Way. It has an exoplanet named WASP-21b. A survey in 2012 failed to find any stellar companions to WASP-21.
== Naming == In 2019 the WASP-21 system was chosen as part of the NameExoWorlds campaign organised by the International Astronomical Union, which assigned each country a star and planet to be named. WASP-21 was assigned to Bulgaria. The winning proposal named the star Tangra after a deity worshipped by the early Bulgars, and the planet Bendida after a deity worshipped by the Thracians.
== Planetary system == In 2010 WASP-21 was discovered to host a hot Jupiter type planet by the Wide Angle Search for Planets (WASP), confirmed by radial velocity by the WASP team in 2010. Transit-timing variation analysis in 2015 did not find any additional planets in the system. In 2020, spectroscopic analysis found that the WASP-21b atmosphere is mostly cloudless and contains sodium.
== References ==