Star system, 160 light-years
HD 209458 and its one planet
HD 209458 b is an exoplanet 15.581 times Earth's width, about 1.4 times Jupiter's, 160 light-years away, orbiting closer to its star than the habitable zone we compute for it.
HD 209458 is a star of spectral type G0 V, 160 light-years from us, with one known planet.
Drawn at the system's own scale, every orbit from the Archive's numbers.
What is measured, what is computed, what is imagined.
measured The period, and where the table says so the width and the mass, by the method named in each section.
computed Anything marked computed: the size of an orbit where Kepler's third law corrects the table, the temperature of a bare ball at that distance, the starlight received, and the habitable zone.
imagined The picture is an artist's impression. Nobody has seen the surface of a planet of another star: its colour, clouds and land are not known, and the share picture says so in its corner.
HD 209458 b
HD 209458 b is an exoplanet 15.581 times Earth's width, about 1.4 times Jupiter's, 160 light-years away, orbiting closer to its star than the habitable zone we compute for it.
- Width
- 15.581 × Earth's measured
- Mass
- 232.016 times Earth's measured
- One year
- 3.52475 days measured
- Distance from its star
- 0.04857 au computed from the period and the star's mass
- Temperature of a bare ball there
- 1,319 K computed, not measured
- Starlight, against Earth's
- 721 × computed
It was found by the back-and-forth wobble its pull puts into its star's motion, seen as a shift in the colour of the star's light in 1999. Its orbit is closer to its star than the habitable zone computed for it. The Archive's own distance for it is 0.04707 au; the three papers behind its period, its star's mass and that distance do not agree with Kepler's third law, so the page uses the one the period and the star's mass give.
See HD 209458 b in 3D · The picture is an artist's impression.
The star
- Surface temperature
- 6,091 K
- Width
- 1.19 × the Sun's
- Mass
- 1.23 × the Sun's
- Spectral type
- G0 V
- Distance
- 160 light-years
- Habitable zone, computed
- 1.217 to 2.13 au from the star