NASA (Exoplanet Catalog artwork)HR 8799 e
Part of the first directly imaged multi-planet system, now seen moving in a decade-long movie
Overview
HR 8799 e is a large exoplanet, orbiting the star HR 8799, which lies 129 light-years from Earth. This gas giant has 7.5 times the mass of Jupiter and 1.13 times its radius. Due to their young age, all four discovered planets in the HR 8799 system are large, compared to all gas giants in the Solar System.
Source: Wikipedia
NASA: HR 8799 e is a gas giant exoplanet that orbits a F-type star. Its mass is 10 Jupiters, it takes 57 years to complete one orbit of its star, and is 16.4 AU from its star. Its discovery was announced in 2010.
Why it matters
- HR 8799 hosts four imaged giant planets; e was added in 2010 and is the innermost.
- First exoplanet observed with optical interferometry (GRAVITY, 2019), revealing a cloudy, stormy atmosphere.
- JWST detected carbon dioxide in the planets' atmospheres in 2025, favouring core-accretion formation.
NASA puts it this way: “HR 8799 e is a gas giant exoplanet that orbits an F-type star. Its mass is 10 Jupiters, it takes 57 years to complete one orbit of its star, and is 16.4 AU from its star. Its discovery was announced in 2010.”
Discovery & system
- Discovered
- 2010 · Imaging · W. M. Keck Observatory
- Discovery paper
- Marois et al. 2010
- Host star
- HR 8799 · A5 · 7,400 K · 1.51 M☉
- System
- 4 known planets
- Siblings
- HR 8799 d, HR 8799 c, HR 8799 b
The system
| World | Period | Distance | Radius | Mass | Temp. |
|---|---|---|---|---|---|
| HR 8799 e | 57 yr | 16.4 AU | 1.17 R♃ | 10 M♃ | 1,150 K |
| HR 8799 d | 101.3 yr | 24 AU | 1.16 R♃ | 9.44 M♃ | 1,300 K |
| HR 8799 c | 188.9 yr | 38 AU | 1.16 R♃ | 9.44 M♃ | 1,200 K |
| HR 8799 b | 465.4 yr | 68 AU | 1.16 R♃ | 6.29 M♃ | 1,200 K |
By the numbers
- Radius
- 1.17 R♃13.1 R⊕
- Mass
- 10 M♃3,178 M⊕
- Orbital period
- 57 yr
- Distance from star
- 16.4 AU2,453 million km
- Eccentricity
- 0.15elliptical
- Equilibrium temp.
- 1,150 K877 °C
- Starlight received
- 0.02 × Earth
- Distance from Earth
- 135 ly41.2 pc
- Density
- 7.74 g/cm³1.4 × Earth
Sources
Image: NASA (Exoplanet Catalog artwork) · NASA media: generally free of copyright · image page
Text: Wikipedia (CC BY-SA 4.0). Taglines and highlights are editorial.