HAT-P-44 b
HAT-P-44 b is a hot Jupiter orbiting HAT-P-44 in the constellation Boötes. It lies about 1,135 light-years from Earth and was discovered in 2014 using the transit method.
How Big Is HAT-P-44 b?
HAT-P-44 b has a radius of 13.92 times that of Earth, or 1.24 times the radius of Jupiter. Its mass is 112 times that of Earth, giving it a density of 0.23 g/cm³ — closer to gas planets like Jupiter (1.33 g/cm³).
Is HAT-P-44 b in the Habitable Zone?
HAT-P-44 b orbits inside the inner edge of the habitable zone of HAT-P-44. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HAT-P-44: 0.617–1.476 AU (conservative: 0.782–1.399 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 HAT-P-44 b
The equilibrium temperature of HAT-P-44 b is about 1,108 K (835 °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 HAT-P-44 b — one full orbit around HAT-P-44 — lasts 4.30 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.051 AU — closer to its star than Mercury is to the Sun. Its orbit is nearly circular (eccentricity 0.044).
How Was HAT-P-44 b Discovered?
HAT-P-44 b was discovered in 2014 using the transit method, with observations from HATNet.
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 HAT-P-44 b?
HAT-P-44 b is 1,134.5 light-years (347.9 parsecs) from Earth. Light arriving here tonight left the planet about 1,135 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 19,967,200 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. HAT-P-44 b scores 0.07, ranking #4,966 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: HAT-P-44
HAT-P-44
- Surface temperature
- 5,295 K (Sun: 5,772 K)
- Mass
- 0.94 M☉
- Radius
- 0.95 R☉
- Luminosity
- 0.6397 L☉
- Age
- 7.5 billion years (Sun: 4.6)
The HAT-P-44 Planetary System
HAT-P-44 b is one of 2 known planets in the HAT-P-44 system. Its siblings:
- HAT-P-44 c (Cold Gas Giant)
HAT-P-44 b — Complete Data
| Radius | 13.922 Earth radii (1.242 Jupiter radii) |
|---|---|
| Mass | 111.87 Earth masses (0.352 Jupiter masses) |
| Density | 0.23 g/cm³ (Earth: 5.51) |
| Orbital period | 4.30 days |
| Orbital distance | 0.051 AU |
| Eccentricity | 0.044 |
| Equilibrium temperature | 1,108 K (835 °C) |
| Earth Similarity Index | 0.07 |
| Distance from Earth | 1,134.5 light-years (347.9 parsecs) |
| Constellation | Boötes |
| Discovery method | Transit |
| Discovery facility | HATNet |
| Discovery year | 2014 |
Data: NASA Exoplanet Archive, last updated 2014-05-14. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HAT-P-44 b
Is HAT-P-44 b habitable?
No — HAT-P-44 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HAT-P-44 b?
HAT-P-44 b is about 1,135 light-years from Earth in the constellation Boötes. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 19,967,200 years to get there.
How big is HAT-P-44 b compared to Earth?
HAT-P-44 b has 13.92 times the radius of Earth and about 112 times its mass.
How long is a year on HAT-P-44 b?
One orbit around HAT-P-44 takes 4.3 Earth days — short enough that 85 of its years would fit into one Earth year.
Explore HAT-P-44 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.
