GJ 433 b
GJ 433 b is a super-Earth orbiting GJ 433 in the constellation Hydra. It lies about 30 light-years from Earth and was discovered in 2013 using the radial velocity method.
Is GJ 433 b in the Habitable Zone?
The position of GJ 433 b relative to the habitable zone of GJ 433 cannot be precisely determined from the available orbital data.
Orbit and Year Length
A year on GJ 433 b — one full orbit around GJ 433 — lasts 7.37 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.062 AU — closer to its star than Mercury is to the Sun. Its orbit is nearly circular (eccentricity 0.040).
How Was GJ 433 b Discovered?
GJ 433 b was discovered in 2013 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 GJ 433 b?
GJ 433 b is 29.6 light-years (9.1 parsecs) from Earth. Light arriving here tonight left the planet around the year 1997. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 520,960 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. GJ 433 b scores 0.44, ranking #351 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: GJ 433
GJ 433
- Mass
- 0.48 M☉
The GJ 433 Planetary System
GJ 433 b is one of 3 known planets in the GJ 433 system. Its siblings:
GJ 433 b — Complete Data
| Mass (best estimate) | 6.04 Earth masses |
|---|---|
| Orbital period | 7.37 days |
| Orbital distance | 0.062 AU |
| Eccentricity | 0.040 |
| Earth Similarity Index | 0.44 |
| Distance from Earth | 29.6 light-years (9.1 parsecs) |
| Constellation | Hydra |
| Discovery method | Radial Velocity |
| Discovery facility | La Silla Observatory |
| Discovery year | 2013 |
Data: NASA Exoplanet Archive, last updated 2020-02-06. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About GJ 433 b
Is GJ 433 b habitable?
GJ 433 b is not known to orbit within the habitable zone of GJ 433, and as a super-Earth it is an unlikely candidate for life as we know it.
How far away is GJ 433 b?
GJ 433 b is about 30 light-years from Earth in the constellation Hydra. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 520,960 years to get there.
How long is a year on GJ 433 b?
One orbit around GJ 433 takes 7.4 Earth days — short enough that 50 of its years would fit into one Earth year.
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