Exoplanet · gas giant
HD 217786 b
HD 217786 b is a gas giant orbiting the star HD 217786. Its year lasts 1,300 Earth days. It was discovered in 2011 by the Radial Velocity method.
| Host star | HD 217786 |
|---|---|
| Distance | 181.0 light-years (55.5 pc) |
| Orbital period | 3.56 years |
| Orbital radius | 2.45 AU |
| Eccentricity | 0.311 |
| Radius | 12.3 R⊕ · 1.1 R♃ |
| Mass | 4,400 M⊕ · 13.9 M♃ |
| Density | 13 g/cm³ |
| Surface gravity | 29.1 × Earth |
| Equilibrium temperature | 207 K (-66 °C) |
| Stellar flux received | 0.316 × Earth |
| Discovery method | Radial Velocity |
| Discovery year | 2011 |
| Discovered by | La Silla Observatory |
Habitable zone
Beyond the habitable zone: it receives only %32 of the light the Earth does, a frozen world.
Its star in the sky
In the planet's sky its star is a disc 0.28° across: 0.52 times the Sun as we see it from Earth.
In the sky
Too faint for the naked eye (magnitude 7.78); binoculars will find it. Visible from the whole Southern Hemisphere and north to latitude 90° N. 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 1845. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 3.2 million years.
Planets in the same system
- HD 217786 c 2.52-day orbit · 2.61 R⊕
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.