Exoplanet · gas giant
HD 18438 b
HD 18438 b is a gas giant orbiting the star HD 18438. Its year lasts 803 Earth days. It was discovered in 2023 by the Radial Velocity method.
| Host star | HD 18438 |
|---|---|
| Distance | 731.1 light-years (224.1 pc) |
| Orbital period | 2.2 years |
| Orbital radius | 2.1 AU |
| Eccentricity | 0.100 |
| Radius | 12.1 R⊕ · 1.08 R♃ |
| Mass (minimum) | 6,670 M⊕ · 21 M♃ |
| Density | 20.7 g/cm³ |
| Equilibrium temperature | 1,208 K (935 °C) |
| Stellar flux received | 211 × Earth |
| Discovery method | Radial Velocity |
| Discovery year | 2023 |
| Discovered by | Bohyunsan Optical Astronomical Observatory |
Habitable zone
Inside the inner edge of the habitable zone: it receives 211 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 22° across: 42 times the Sun as we see it from Earth.
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.49). Visible from the whole Northern Hemisphere and south to latitude 11° S. North of latitude 11° N it never sets.
Light's journey
The light you see tonight set out around the year 1295. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 13 million years.
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.