TOI-564 b
TOI-564 b is a hot Jupiter orbiting TOI-564 in the constellation Hydra. It lies about 651 light-years from Earth and was discovered in 2020 using the transit method.
How Big Is TOI-564 b?
TOI-564 b has a radius of 11.43 times that of Earth, or 1.02 times the radius of Jupiter. Its mass is 465 times that of Earth, giving it a density of 1.70 g/cm³ — closer to gas planets like Jupiter (1.33 g/cm³).
Is TOI-564 b in the Habitable Zone?
TOI-564 b orbits inside the inner edge of the habitable zone of TOI-564. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of TOI-564: 0.786–1.858 AU (conservative: 0.995–1.762 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 TOI-564 b
The equilibrium temperature of TOI-564 b is about 1,714 K (1,441 °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. It receives 1,423 times the stellar energy that Earth gets from the Sun.
Orbit and Year Length
A year on TOI-564 b — one full orbit around TOI-564 — lasts just 39.6 hours, shorter than Mercury's 88-day year. It orbits at an average distance of 0.027 AU — closer to its star than Mercury is to the Sun. Its orbit is mildly elliptical (eccentricity 0.07).
How Was TOI-564 b Discovered?
TOI-564 b was discovered in 2020 using the transit method, with observations from Transiting Exoplanet Survey Satellite (TESS).
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 TOI-564 b?
TOI-564 b is 650.9 light-years (199.6 parsecs) from Earth. Light arriving here tonight left the planet around the year 1376. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 11,455,840 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. TOI-564 b scores 0.08, ranking #4,719 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: TOI-564
TOI-564
- Surface temperature
- 5,640 K (Sun: 5,772 K)
- Mass
- 1.00 M☉
- Radius
- 1.09 R☉
- Luminosity
- 1.0780 L☉
- Age
- 7.3 billion years (Sun: 4.6)
Planetary System
TOI-564 b is the only planet known to orbit TOI-564 so far.
TOI-564 b — Complete Data
| Radius | 11.433 Earth radii (1.020 Jupiter radii) |
|---|---|
| Mass | 464.99 Earth masses (1.463 Jupiter masses) |
| Density | 1.70 g/cm³ (Earth: 5.51) |
| Orbital period | 1.65 days |
| Orbital distance | 0.027 AU |
| Eccentricity | 0.072 |
| Equilibrium temperature | 1,714 K (1,441 °C) |
| Stellar irradiation | 1,423.00× Earth |
| Earth Similarity Index | 0.08 |
| Distance from Earth | 650.9 light-years (199.6 parsecs) |
| Constellation | Hydra |
| Discovery method | Transit |
| Discovery facility | Transiting Exoplanet Survey Satellite (TESS) |
| Discovery year | 2020 |
Data: NASA Exoplanet Archive, last updated 2021-02-08. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About TOI-564 b
Is TOI-564 b habitable?
No — TOI-564 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is TOI-564 b?
TOI-564 b is about 651 light-years from Earth in the constellation Hydra. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 11,455,840 years to get there.
How big is TOI-564 b compared to Earth?
TOI-564 b has 11.43 times the radius of Earth and about 465 times its mass.
How long is a year on TOI-564 b?
One orbit around TOI-564 takes 1.7 Earth days — short enough that 221 of its years would fit into one Earth year.
Explore TOI-564 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.
