Exoplanet · gas giant
K2-308 b
K2-308 b is a gas giant orbiting the star K2-308. Its year lasts 3.39 Earth days. It was discovered in 2019 by the Transit method.
| Host star | K2-308 |
|---|---|
| Distance | 4,287 light-years (1,315 pc) |
| Orbital period | 3.39 days |
| Radius | 9.92 R⊕ · 0.885 R♃ |
| Mass | 70.6 M⊕ · 0.222 M♃ (estimated from the radius) |
| Density | 0.398 g/cm³ |
| Equilibrium temperature | 1,214 K (941 °C) |
| Stellar flux received | 513 × Earth |
| Discovery method | Transit |
| Discovery year | 2019 |
| Discovered by | K2 |
Habitable zone
Inside the inner edge of the habitable zone: it receives 513 times the light the Earth does, too hot to keep liquid water on its surface.
In the sky
A telescope is needed to see it: its apparent magnitude is 15.07. Visible from the whole Northern Hemisphere and south to latitude 74° S. North of latitude 74° N it never sets. It stands highest at midnight in December, the best time to observe it.
Light's journey
The light you see tonight set out 4,287 years ago. At that time the first farming villages were being founded; there was no writing yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 76 million years.
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.