Exoplanet · mini-Neptune
K2-217 b
K2-217 b is a mini-Neptune orbiting the star K2-217. Its year lasts 14.1 Earth days. It was discovered in 2018 by the Transit method.
| Host star | K2-217 |
|---|---|
| Distance | 1,246 light-years (381.9 pc) |
| Orbital period | 14.1 days |
| Radius | 3.58 R⊕ · 0.319 R♃ |
| Mass | 12.5 M⊕ · 0.0393 M♃ (estimated from the radius) |
| Density | 1.5 g/cm³ |
| Discovery method | Transit |
| Discovery year | 2018 |
| Discovered by | K2 |
In the sky
A telescope is needed to see it: its apparent magnitude is 12.26. Visible from the whole Northern Hemisphere and south to latitude 84° S. It stands highest at midnight in September, the best time to observe it.
Light's journey
The light you see tonight set out around the year 780. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 22 million years.
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.