TOI-873 b
TOI-873 b is a super-Earth orbiting TOI-873 in the constellation Reticulum. It lies about 251 light-years from Earth and was discovered in 2026 using the transit method.
How Big Is TOI-873 b?
TOI-873 b has a radius of 1.65 times that of Earth.
Is TOI-873 b in the Habitable Zone?
The position of TOI-873 b relative to the habitable zone of TOI-873 cannot be precisely determined from the available orbital data.
Habitable zone of TOI-873: 0.174–0.447 AU (conservative: 0.220–0.424 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.
See the full interactive habitable-zone view in the Exoplanet Explorer app ›
Orbit and Year Length
A year on TOI-873 b — one full orbit around TOI-873 — lasts 5.93 Earth days, shorter than Mercury's 88-day year.
How Was TOI-873 b Discovered?
TOI-873 b was discovered in 2026 using the transit method, with observations from Transiting Exoplanet Survey Satellite (TESS).
The transit method watches a star for the tiny, regular dip in brightness that occurs when a planet crosses in front of it. The depth and timing of these dips reveal the planet's size and orbital period.
How Far Away Is TOI-873 b?
TOI-873 b is 251.0 light-years (77.0 parsecs) from Earth. Light arriving here tonight left the planet around the year 1775. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 4,417,600 years to make the journey.
The Host Star: TOI-873
TOI-873
- Surface temperature
- 3,694 K (Sun: 5,772 K)
- Mass
- 0.52 M☉
- Radius
- 0.52 R☉
- Luminosity
- 0.0454 L☉
Planetary System
TOI-873 b is the only planet known to orbit TOI-873 so far.
TOI-873 b — Complete Data
| Radius | 1.650 Earth radii (0.147 Jupiter radii) |
|---|---|
| Orbital period | 5.93 days |
| Distance from Earth | 251.0 light-years (77.0 parsecs) |
| Constellation | Reticulum |
| Discovery method | Transit |
| Discovery facility | Transiting Exoplanet Survey Satellite (TESS) |
| Discovery year | 2026 |
Data: NASA Exoplanet Archive, last updated 2026-10-08. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About TOI-873 b
Is TOI-873 b habitable?
TOI-873 b is not known to orbit within the habitable zone of TOI-873, and as a super-Earth it is an unlikely candidate for life as we know it.
How far away is TOI-873 b?
TOI-873 b is about 251 light-years from Earth in the constellation Reticulum. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 4,417,600 years to get there.
How big is TOI-873 b compared to Earth?
TOI-873 b has 1.65 times the radius of Earth.
How long is a year on TOI-873 b?
One orbit around TOI-873 takes 5.9 Earth days — short enough that 62 of its years would fit into one Earth year.