ZTF J1828+2308 is 658 light-years from the Sun. The NASA Exoplanet Archive lists 1 planet around this 15,900 K star; the first was found in 2025 by transit (Zwicky Transient Facility).
Fly there in 3DZTF J1828+2308 b goes round its star every 2.7 hours, 786 times as often as Mercury goes round the Sun.
Where the archive gives only a period or only an orbit size, the other is worked out from Kepler’s third law with the star’s mass.
| Surface temperature | 15,900 K |
| Mass | 0.61 solar masses |
| Radius | 0.0131 solar radii |
| Luminosity | 0.01 times the Sun |
| Apparent magnitude | 18.0447 |
| Distance from the Sun | 658.3 light-years (201.8 parsecs) |
| Position (J2000) | RA 277.2032°, Dec 23.1439° |
| Constellation | Hercules |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| ZTF J1828+2308 b | 2.7 hours | 0.0039 AU from Kepler’s law | 11.131 R⊕ | 6356.6 M⊕ | Transit, 2025 |
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.