| KELT-20b | |
| Discovery Site: | KELT |
| Discovered: | 2017 |
| Apsis: | astron |
| Semimajor: | 0.0542 AU |
| Period: | 3.6127647 d = 3.474 |
| Inclination: | 86.12 |
| Mean Radius: | 1.741 |
| Mass: | <3.382 |
| Density: | <0.806 g cm−3 |
KELT-20b, also known as MASCARA-2b, was an exoplanet announced in 2017. It is an Ultra-hot Jupiter orbiting an A-type star. The carbon monoxide, steam and neutral iron detection in the atmosphere of KELT-20b was announced in 2022.
See main article: KELT-20. The host star is an A-type main-sequence star in the constellation of Cygnus having 2.282 solar masses, 1.617 solar radius and an apparent magnitude of 7.58.