HD 43197 b
HD 43197 b is a cold gas giant orbiting HD 43197 in the constellation Canis Major. It lies about 204 light-years from Earth and was discovered in 2010 using the radial velocity method.
Is HD 43197 b in the Habitable Zone?
The position of HD 43197 b relative to the habitable zone of HD 43197 cannot be precisely determined from the available orbital data.
Orbit and Year Length
A year on HD 43197 b — one full orbit around HD 43197 — lasts 308.9 Earth days, between the years of Mercury (88 days) and Earth (365 days). It orbits at an average distance of 0.882 AU — comparable to the inner Solar System. Its orbit is highly elliptical (eccentricity 0.74), swinging dramatically closer to and farther from its star.
How Was HD 43197 b Discovered?
HD 43197 b was discovered in 2010 using the radial velocity method, with observations from La Silla 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 43197 b?
HD 43197 b is 203.6 light-years (62.4 parsecs) from Earth. Light arriving here tonight left the planet around the year 1823. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 3,583,360 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 43197 b scores 0.37, ranking #599 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: HD 43197
HD 43197
- Mass
- 0.96 M☉
The HD 43197 Planetary System
HD 43197 b is one of 2 known planets in the HD 43197 system. Its siblings:
- HD 43197 c (Cold Gas Giant)
HD 43197 b — Complete Data
| Mass (best estimate) | 175.76 Earth masses |
|---|---|
| Orbital period | 308.92 days |
| Orbital distance | 0.882 AU |
| Eccentricity | 0.742 |
| Earth Similarity Index | 0.37 |
| Distance from Earth | 203.6 light-years (62.4 parsecs) |
| Constellation | Canis Major |
| Discovery method | Radial Velocity |
| Discovery facility | La Silla Observatory |
| Discovery year | 2010 |
Data: NASA Exoplanet Archive, last updated 2023-06-14. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HD 43197 b
Is HD 43197 b habitable?
HD 43197 b is not known to orbit within the habitable zone of HD 43197, and as a cold gas giant it is an unlikely candidate for life as we know it.
How far away is HD 43197 b?
HD 43197 b is about 204 light-years from Earth in the constellation Canis Major. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 3,583,360 years to get there.
How long is a year on HD 43197 b?
One orbit around HD 43197 takes 308.9 Earth days.
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