HD 8574 b
HD 8574 b is a cold gas giant orbiting HD 8574 in the constellation Pisces. It lies about 146 light-years from Earth and was discovered in 2002 using the radial velocity method.
Is HD 8574 b in the Habitable Zone?
HD 8574 b orbits inside the inner edge of the habitable zone of HD 8574. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HD 8574: 1.121–2.623 AU (conservative: 1.420–2.487 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 HD 8574 b — one full orbit around HD 8574 — lasts 227.0 Earth days, between the years of Mercury (88 days) and Earth (365 days). It orbits at an average distance of 0.760 AU — comparable to the inner Solar System. Its orbit is highly elliptical (eccentricity 0.30), swinging dramatically closer to and farther from its star.
How Was HD 8574 b Discovered?
HD 8574 b was discovered in 2002 using the radial velocity method, with observations from Haute-Provence Observatory.
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 HD 8574 b?
HD 8574 b is 146.2 light-years (44.8 parsecs) from Earth. Light arriving here tonight left the planet around the year 1880. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 2,573,120 years to make the journey.
Earth Similarity Index
The Earth Similarity Index (ESI) scores how physically similar a planet is to Earth, from 0 to 1, based on radius, density, escape velocity and surface temperature. HD 8574 b scores 0.25, ranking #3,144 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: HD 8574
HD 8574
- Surface temperature
- 6,064 K (Sun: 5,772 K)
- Mass
- 1.34 M☉
- Radius
- 1.38 R☉
Planetary System
HD 8574 b is the only planet known to orbit HD 8574 so far.
HD 8574 b — Complete Data
| Mass (best estimate) | 645.19 Earth masses |
|---|---|
| Orbital period | 227.00 days |
| Orbital distance | 0.760 AU |
| Eccentricity | 0.300 |
| Earth Similarity Index | 0.25 |
| Distance from Earth | 146.2 light-years (44.8 parsecs) |
| Constellation | Pisces |
| Discovery method | Radial Velocity |
| Discovery facility | Haute-Provence Observatory |
| Discovery year | 2002 |
Data: NASA Exoplanet Archive, last updated 2018-09-04. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HD 8574 b
Is HD 8574 b habitable?
No — HD 8574 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HD 8574 b?
HD 8574 b is about 146 light-years from Earth in the constellation Pisces. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 2,573,120 years to get there.
How long is a year on HD 8574 b?
One orbit around HD 8574 takes 227.0 Earth days.
Explore HD 8574 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.
