KELT-21 b
A confirmed exoplanet orbiting KELT-21.
Compared with Earth
- Size
- About 18 times Earth's width.
- Mass
- About 1,243 times Earth's mass.
- Temperature
- About 1,778 °C (3,232 °F) from starlight alone, against -18 °C (-1 °F) for Earth measured the same way.
- Starlight
- About 2,950 times the starlight Earth gets from the Sun.
- Year
- A year here lasts about 3.6 Earth days.
Planet
- Radius
- 17.78 × Earth
- Mass
- 1,243 × Earth
- Density
- 1.24 g/cm³
- Equilibrium temperature
- 2,051 K
- Starlight received
- 2,950 × Earth
- Orbital period
- 3.613 days
- Average distance from its star
- 0.05224 AU
Star
- Host star
- KELT-21
- Spectral class
- A — white
- Surface temperature
- 7,598 K
- Radius
- 1.638 × Sun
- Mass
- 1.458 × Sun
- Age
- 1.6 billion years
System
- Distance from Earth
- 1,536 light-years (470.9 parsecs)
- Stars in system
- 1
- Known planets
- 1
Discovery
- Year
- 2018
- Method
- Transit
- Facility
- KELT-North
Data from the NASA Exoplanet Archive, synced October 14, 2026.