HD 73344 b
HD 73344 b is a mini-Neptune orbiting the F6 V star HD 73344 in the constellation Cancer. It lies about 115 light-years from Earth and was discovered in 2024 using the transit method.
How Big Is HD 73344 b?
HD 73344 b has a radius of 2.88 times that of Earth. Its mass is 10.5 times that of Earth, giving it a density of 2.45 g/cm³ — between that of rocky and gaseous planets.
Is HD 73344 b in the Habitable Zone?
HD 73344 b orbits inside the inner edge of the habitable zone of HD 73344. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HD 73344: 1.042–2.428 AU (conservative: 1.319–2.302 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.
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Temperature on HD 73344 b
The equilibrium temperature of HD 73344 b is about 911 K (638 °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 HD 73344 b — one full orbit around HD 73344 — lasts 15.6 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.131 AU — closer to its star than Mercury is to the Sun. Its orbit is nearly circular (eccentricity 0.030).
How Was HD 73344 b Discovered?
HD 73344 b was discovered in 2024 using the transit method, with observations from K2.
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 HD 73344 b?
HD 73344 b is 115.0 light-years (35.3 parsecs) from Earth. Light arriving here tonight left the planet around the year 1911. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 2,024,000 years to make the journey.
The Host Star: HD 73344
HD 73344
- Spectral type
- F6 V
- Surface temperature
- 6,253 K (Sun: 5,772 K)
- Mass
- 1.20 M☉
- Radius
- 1.22 R☉
- Age
- 1.2 billion years (Sun: 4.6)
The HD 73344 Planetary System
HD 73344 b is one of 3 known planets in the HD 73344 system. Its siblings:
- HD 73344 c (Cold Gas Giant)
- HD 73344 d (Cold Gas Giant)
HD 73344 b — Complete Data
| Radius | 2.884 Earth radii (0.257 Jupiter radii) |
|---|---|
| Mass | 10.48 Earth masses (0.033 Jupiter masses) |
| Density | 2.45 g/cm³ (Earth: 5.51) |
| Orbital period | 15.61 days |
| Orbital distance | 0.131 AU |
| Eccentricity | 0.030 |
| Equilibrium temperature | 911 K (638 °C) |
| Distance from Earth | 115.0 light-years (35.3 parsecs) |
| Constellation | Cancer |
| Discovery method | Transit |
| Discovery facility | K2 |
| Discovery year | 2024 |
Data: NASA Exoplanet Archive, last updated 2024-06-10. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HD 73344 b
Is HD 73344 b habitable?
No — HD 73344 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HD 73344 b?
HD 73344 b is about 115 light-years from Earth in the constellation Cancer. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 2,024,000 years to get there.
How big is HD 73344 b compared to Earth?
HD 73344 b has 2.88 times the radius of Earth and about 10.5 times its mass.
How long is a year on HD 73344 b?
One orbit around HD 73344 takes 15.6 Earth days — short enough that 23 of its years would fit into one Earth year.
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