KELT-21 is 1,536 light-years from the Sun. The NASA Exoplanet Archive lists 1 planet around this A8 V star; the first was found in 2018 by transit (KELT-North).
Fly there in 3DKELT-21 b goes round its star every 3.61 days, 24 times as often as Mercury goes round the Sun.
| Spectral type | A8 V |
| Surface temperature | 7,598 K |
| Mass | 1.458 solar masses |
| Radius | 1.638 solar radii |
| Luminosity | 8.03 times the Sun |
| Apparent magnitude | 10.484 |
| Age | about 1.6 billion years |
| Distance from the Sun | 1535.8 light-years (470.9 parsecs) |
| Position (J2000) | RA 304.8000°, Dec 32.5810° |
| Constellation | Cygnus |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| KELT-21 b | 3.61 days | 0.0522 AU | 17.777 R⊕ | 1242.7 M⊕ | Transit, 2018 |
Values are the NASA Exoplanet Archive’s composite parameters. A radius marked estimated comes from a mass–radius relation; a mass marked minimum is M sin i. Planet sizes and colours in the 3D view are renderings: none of these worlds has been photographed as more than a point of light.