TOI-5789 e
TOI-5789 e is a Neptune-like planet orbiting the K1 V star TOI-5789 in the constellation Sagitta. It lies about 67 light-years from Earth and was discovered in 2026 using the radial velocity method.
Is TOI-5789 e in the Habitable Zone?
TOI-5789 e orbits inside the inner edge of the habitable zone of TOI-5789. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of TOI-5789: 0.531–1.276 AU (conservative: 0.673–1.210 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 ›
Temperature on TOI-5789 e
The equilibrium temperature of TOI-5789 e is about 424 K (151 °C) — hotter than anywhere on Earth. This estimate ignores any atmosphere, which could change surface temperatures dramatically — Earth's greenhouse effect adds about 33 °C.
Orbit and Year Length
A year on TOI-5789 e — one full orbit around TOI-5789 — lasts 63.0 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.290 AU — closer to its star than Mercury is to the Sun. Its orbit is mildly elliptical (eccentricity 0.07).
How Was TOI-5789 e Discovered?
TOI-5789 e was discovered in 2026 using the radial velocity method, with observations from Multiple Observatories.
The radial velocity method measures the subtle wobble of a star caused by the gravitational pull of an orbiting planet, visible as periodic shifts in the star's light spectrum. The size of the wobble reveals the planet's minimum mass.
How Far Away Is TOI-5789 e?
TOI-5789 e is 66.7 light-years (20.5 parsecs) from Earth. Light arriving here tonight left the planet around the year 1960. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 1,173,920 years to make the journey.
The Host Star: TOI-5789
TOI-5789
- Spectral type
- K1 V
- Surface temperature
- 5,185 K (Sun: 5,772 K)
- Mass
- 0.82 M☉
- Radius
- 0.83 R☉
- Luminosity
- 0.4690 L☉
- Age
- 9.4 billion years (Sun: 4.6)
The TOI-5789 Planetary System
TOI-5789 e is one of 4 known planets in the TOI-5789 system. Its siblings:
- TOI-5789 b (Super Earth)
- TOI-5789 c (Puffy Planet)
- TOI-5789 d (Super Earth)
TOI-5789 e — Complete Data
| Mass (best estimate) | 11.61 Earth masses |
|---|---|
| Orbital period | 62.98 days |
| Orbital distance | 0.290 AU |
| Eccentricity | 0.071 |
| Equilibrium temperature | 424 K (151 °C) |
| Distance from Earth | 66.7 light-years (20.5 parsecs) |
| Constellation | Sagitta |
| Discovery method | Radial Velocity |
| Discovery facility | Multiple Observatories |
| Discovery year | 2026 |
Data: NASA Exoplanet Archive, last updated 2026-01-29. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About TOI-5789 e
Is TOI-5789 e habitable?
No — TOI-5789 e orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is TOI-5789 e?
TOI-5789 e is about 67 light-years from Earth in the constellation Sagitta. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 1,173,920 years to get there.
How long is a year on TOI-5789 e?
One orbit around TOI-5789 takes 63.0 Earth days.