TOI-3851 b
TOI-3851 b is a Neptune-like planet orbiting TOI-3851 in the constellation Draco. It lies about 973 light-years from Earth and was discovered in 2026 using the transit method.
How Big Is TOI-3851 b?
TOI-3851 b has a radius of 4.76 times that of Earth.
Is TOI-3851 b in the Habitable Zone?
The position of TOI-3851 b relative to the habitable zone of TOI-3851 cannot be precisely determined from the available orbital data.
Habitable zone of TOI-3851: 0.940–2.210 AU (conservative: 1.190–2.095 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-3851 b — one full orbit around TOI-3851 — lasts 3.38 Earth days, shorter than Mercury's 88-day year.
How Was TOI-3851 b Discovered?
TOI-3851 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-3851 b?
TOI-3851 b is 973.1 light-years (298.3 parsecs) from Earth. Light arriving here tonight left the planet around the year 1053. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 17,126,560 years to make the journey.
The Host Star: TOI-3851
TOI-3851
- Surface temperature
- 5,838 K (Sun: 5,772 K)
- Mass
- 1.05 M☉
- Radius
- 1.23 R☉
- Luminosity
- 1.5788 L☉
Planetary System
TOI-3851 b is the only planet known to orbit TOI-3851 so far.
TOI-3851 b — Complete Data
| Radius | 4.760 Earth radii (0.425 Jupiter radii) |
|---|---|
| Orbital period | 3.38 days |
| Distance from Earth | 973.1 light-years (298.3 parsecs) |
| Constellation | Draco |
| 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-3851 b
Is TOI-3851 b habitable?
TOI-3851 b is not known to orbit within the habitable zone of TOI-3851, and as a Neptune-like planet it is an unlikely candidate for life as we know it.
How far away is TOI-3851 b?
TOI-3851 b is about 973 light-years from Earth in the constellation Draco. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 17,126,560 years to get there.
How big is TOI-3851 b compared to Earth?
TOI-3851 b has 4.76 times the radius of Earth.
How long is a year on TOI-3851 b?
One orbit around TOI-3851 takes 3.4 Earth days — short enough that 108 of its years would fit into one Earth year.
Explore TOI-3851 b in the app
Browse, filter and compare 6,000+ exoplanets on iPhone, iPad and Apple Watch — with habitable-zone views, widgets and offline data.
