Exoplanet · mini-Neptune
HD 168009 b
HD 168009 b is a mini-Neptune orbiting the star HD 168009. Its year lasts 15.1 Earth days. It was discovered in 2021 by the Radial Velocity method.
| Host star | HD 168009 |
|---|---|
| Distance | 76.0 light-years (23.3 pc) |
| Orbital period | 15.1 days |
| Orbital radius | 0.119 AU |
| Eccentricity | 0.120 |
| Radius | 3.05 R⊕ · 0.272 R♃ |
| Mass (minimum) | 9.53 M⊕ · 0.03 M♃ |
| Density | 1.85 g/cm³ |
| Equilibrium temperature | 888 K (614 °C) |
| Stellar flux received | 99.4 × Earth |
| Discovery method | Radial Velocity |
| Discovery year | 2021 |
| Discovered by | Multiple Observatories |
Habitable zone
Inside the inner edge of the habitable zone: it receives 99.4 times the light the Earth does, too hot to keep liquid water on its surface.
Its star in the sky
In the planet's sky its star is a disc 5.4° across: 10 times the Sun as we see it from Earth.
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 6.30). Visible from the whole Northern Hemisphere and south to latitude 45° S. North of latitude 45° N it never sets. It stands highest at midnight in June, the best time to observe it.
Light's journey
The light you see tonight set out around the year 1950. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.3 million years.
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.