HD 158996 b
HD 158996 b is a exoplanet orbiting the K5 III star HD 158996 in the constellation Ursa Minor. It lies about 925 light-years from Earth and was discovered in 2018 using the radial velocity method.
Is HD 158996 b in the Habitable Zone?
HD 158996 b orbits inside the inner edge of the habitable zone of HD 158996. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HD 158996: 26.049–65.706 AU (conservative: 32.995–62.295 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 158996 b — one full orbit around HD 158996 — lasts 820.2 Earth days, longer than an Earth year. It orbits at an average distance of 2.100 AU. Its orbit is mildly elliptical (eccentricity 0.13).
How Was HD 158996 b Discovered?
HD 158996 b was discovered in 2018 using the radial velocity method, with observations from Bohyunsan Optical Astronomical 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 158996 b?
HD 158996 b is 925.2 light-years (283.7 parsecs) from Earth. Light arriving here tonight left the planet around the year 1101. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 16,283,520 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 158996 b scores 0.08, ranking #4,748 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: HD 158996
HD 158996
- Spectral type
- K5 III
- Surface temperature
- 4,069 K (Sun: 5,772 K)
- Mass
- 1.80 M☉
- Radius
- 50.30 R☉
- Luminosity
- 1,034.6894 L☉
- Age
- 1.6 billion years (Sun: 4.6)
Planetary System
HD 158996 b is the only planet known to orbit HD 158996 so far.
HD 158996 b — Complete Data
| Mass (best estimate) | 4,449.62 Earth masses |
|---|---|
| Orbital period | 820.20 days |
| Orbital distance | 2.100 AU |
| Eccentricity | 0.130 |
| Earth Similarity Index | 0.08 |
| Distance from Earth | 925.2 light-years (283.7 parsecs) |
| Constellation | Ursa Minor |
| Discovery method | Radial Velocity |
| Discovery facility | Bohyunsan Optical Astronomical Observatory |
| Discovery year | 2018 |
Data: NASA Exoplanet Archive, last updated 2018-04-09. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HD 158996 b
Is HD 158996 b habitable?
No — HD 158996 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HD 158996 b?
HD 158996 b is about 925 light-years from Earth in the constellation Ursa Minor. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 16,283,520 years to get there.
How long is a year on HD 158996 b?
One orbit around HD 158996 takes 820.2 Earth days.
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