HATS-43 b
HATS-43 b is a hot Jupiter orbiting HATS-43 in the constellation Columba. It lies about 1,182 light-years from Earth and was discovered in 2018 using the transit method.
How Big Is HATS-43 b?
HATS-43 b has a radius of 13.23 times that of Earth, or 1.18 times the radius of Jupiter. Its mass is 83.0 times that of Earth, giving it a density of 0.19 g/cm³ — closer to gas planets like Jupiter (1.33 g/cm³).
Is HATS-43 b in the Habitable Zone?
HATS-43 b orbits inside the inner edge of the habitable zone of HATS-43. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HATS-43: 0.493–1.187 AU (conservative: 0.624–1.126 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 HATS-43 b
The equilibrium temperature of HATS-43 b is about 1,003 K (730 °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.
Orbit and Year Length
A year on HATS-43 b — one full orbit around HATS-43 — lasts 4.39 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.049 AU — closer to its star than Mercury is to the Sun. Its orbit is mildly elliptical (eccentricity 0.17).
How Was HATS-43 b Discovered?
HATS-43 b was discovered in 2018 using the transit method, with observations from HATSouth.
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 HATS-43 b?
HATS-43 b is 1,181.6 light-years (362.3 parsecs) from Earth. Light arriving here tonight left the planet about 1,182 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 20,796,160 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. HATS-43 b scores 0.07, ranking #4,817 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: HATS-43
HATS-43
- Surface temperature
- 5,099 K (Sun: 5,772 K)
- Mass
- 0.84 M☉
- Radius
- 0.81 R☉
- Luminosity
- 0.4000 L☉
- Age
- 8.6 billion years (Sun: 4.6)
Planetary System
HATS-43 b is the only planet known to orbit HATS-43 so far.
HATS-43 b — Complete Data
| Radius | 13.227 Earth radii (1.180 Jupiter radii) |
|---|---|
| Mass | 82.95 Earth masses (0.261 Jupiter masses) |
| Density | 0.19 g/cm³ (Earth: 5.51) |
| Orbital period | 4.39 days |
| Orbital distance | 0.049 AU |
| Eccentricity | 0.173 |
| Equilibrium temperature | 1,003 K (730 °C) |
| Earth Similarity Index | 0.07 |
| Distance from Earth | 1,181.6 light-years (362.3 parsecs) |
| Constellation | Columba |
| Discovery method | Transit |
| Discovery facility | HATSouth |
| Discovery year | 2018 |
Data: NASA Exoplanet Archive, last updated 2018-05-22. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HATS-43 b
Is HATS-43 b habitable?
No — HATS-43 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HATS-43 b?
HATS-43 b is about 1,182 light-years from Earth in the constellation Columba. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 20,796,160 years to get there.
How big is HATS-43 b compared to Earth?
HATS-43 b has 13.23 times the radius of Earth and about 83.0 times its mass.
How long is a year on HATS-43 b?
One orbit around HATS-43 takes 4.4 Earth days — short enough that 83 of its years would fit into one Earth year.