Exoplanet · Neptune-like planet
HD 16417 b
HD 16417 b is a Neptune-like planet orbiting the star HD 16417. Its year lasts 17.2 Earth days. It was discovered in 2008 by the Radial Velocity method.
| Host star | HD 16417 |
|---|---|
| Distance | 82.8 light-years (25.4 pc) |
| Orbital period | 17.2 days |
| Orbital radius | 0.14 AU |
| Eccentricity | 0.200 |
| Radius | 5 R⊕ · 0.446 R♃ |
| Mass (minimum) | 22.1 M⊕ · 0.0695 M♃ |
| Density | 0.972 g/cm³ |
| Equilibrium temperature | 964 K (691 °C) |
| Stellar flux received | 142 × Earth |
| Discovery method | Radial Velocity |
| Discovery year | 2008 |
| Discovered by | Anglo-Australian Telescope |
Habitable zone
Inside the inner edge of the habitable zone: it receives 142 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 6.2° across: 12 times the Sun as we see it from Earth.
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.78). Visible from the whole Southern Hemisphere and north to latitude 55° N. South of latitude 55° S it never sets. It stands highest at midnight in October, the best time to observe it.
Light's journey
The light you see tonight set out around the year 1943. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.5 million years.
Data: NASA Exoplanet Archive, PSCompPars. Its look in the simulation is a rendering based on the measured radius, mass and temperature.