HD 715 b
HD 715 b is a cold gas giant orbiting the F8 IV star HD 715 in the constellation Pisces. It lies about 546 light-years from Earth and was discovered in 2026 using the transit method.
How Big Is HD 715 b?
HD 715 b has a radius of 11.99 times that of Earth, or 1.07 times the radius of Jupiter. Its mass is 202 times that of Earth, giving it a density of 0.69 g/cm³ — closer to gas planets like Jupiter (1.33 g/cm³).
Is HD 715 b in the Habitable Zone?
HD 715 b orbits inside the inner edge of the habitable zone of HD 715. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HD 715: 2.032–4.755 AU (conservative: 2.574–4.508 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 HD 715 b
The equilibrium temperature of HD 715 b is about 798 K (525 °C) — hot enough to melt many metals. This estimate ignores any atmosphere, which could change surface temperatures dramatically — Earth's greenhouse effect adds about 33 °C. It receives 67.30 times the stellar energy that Earth gets from the Sun.
Orbit and Year Length
A year on HD 715 b — one full orbit around HD 715 — lasts 56.4 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.336 AU — closer to its star than Mercury is to the Sun. Its orbit is mildly elliptical (eccentricity 0.21).
How Was HD 715 b Discovered?
HD 715 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 HD 715 b?
HD 715 b is 545.5 light-years (167.3 parsecs) from Earth. Light arriving here tonight left the planet around the year 1481. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 9,600,800 years to make the journey.
The Host Star: HD 715
HD 715 b belongs to a system of 2 stars; it orbits HD 715.
HD 715
- Spectral type
- F8 IV
- Surface temperature
- 6,070 K (Sun: 5,772 K)
- Mass
- 1.60 M☉
- Radius
- 2.50 R☉
- Luminosity
- 7.5999 L☉
- Age
- 2.1 billion years (Sun: 4.6)
Planetary System
HD 715 b is the only planet known to orbit HD 715 so far.
HD 715 b — Complete Data
| Radius | 11.994 Earth radii (1.070 Jupiter radii) |
|---|---|
| Mass | 201.82 Earth masses (0.635 Jupiter masses) |
| Density | 0.69 g/cm³ (Earth: 5.51) |
| Orbital period | 56.40 days |
| Orbital distance | 0.336 AU |
| Eccentricity | 0.210 |
| Equilibrium temperature | 798 K (525 °C) |
| Stellar irradiation | 67.30× Earth |
| Distance from Earth | 545.5 light-years (167.3 parsecs) |
| Constellation | Pisces |
| Discovery method | Transit |
| Discovery facility | Transiting Exoplanet Survey Satellite (TESS) |
| Discovery year | 2026 |
Data: NASA Exoplanet Archive, last updated 2026-09-11. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HD 715 b
Is HD 715 b habitable?
No — HD 715 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HD 715 b?
HD 715 b is about 546 light-years from Earth in the constellation Pisces. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 9,600,800 years to get there.
How big is HD 715 b compared to Earth?
HD 715 b has 11.99 times the radius of Earth and about 202 times its mass.
How long is a year on HD 715 b?
One orbit around HD 715 takes 56.4 Earth days.
Explore HD 715 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.
