Exoplanet · gas giant
HD 221420 b
HD 221420 b is a gas giant orbiting the star HD 221420. Its year lasts 10,100 Earth days. It was discovered in 2019 by the Radial Velocity method.
| Host star | HD 221420 |
|---|---|
| Distance | 101.6 light-years (31.1 pc) |
| Orbital period | 27.6 years |
| Orbital radius | 10.2 AU |
| Eccentricity | 0.140 |
| Radius | 12 R⊕ · 1.07 R♃ |
| Mass | 7,280 M⊕ · 22.9 M♃ |
| Density | 23.1 g/cm³ |
| Surface gravity | 50.5 × Earth |
| Equilibrium temperature | 123 K (-150 °C) |
| Stellar flux received | 0.0389 × Earth |
| Discovery method | Radial Velocity |
| Discovery year | 2019 |
| Discovered by | Anglo-Australian Telescope |
Habitable zone
Beyond the habitable zone: it receives only %3.9 of the light the Earth does, a frozen world.
Its star in the sky
In the planet's sky its star is a disc 0.1° across: 0.19 times the Sun as we see it from Earth.
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.82). Visible from the whole Southern Hemisphere and north to latitude 13° N. South of latitude 13° S it never sets.
Light's journey
The light you see tonight set out around the year 1924. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.8 million years.
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.