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EarthNeptuneJupiterHD 147018 b
0.01 AU0.1110100 AU MercuryEarthJupiterNeptune HD 147018 b · 0.24 AU
Diagram, not a photograph. Sizes to scale; distance from the star on a logarithmic scale, worked out from the orbital period and the star’s mass. The planet’s colour shows its equilibrium temperature (warm), not its real colour. Source: NASA Exoplanet Archive.

Confirmed exoplanet · Database record + computed analysis

HD 147018 b

A confirmed world orbiting HD 147018, 131.9 light-years away.

131.9 light-years (40.4 pc) Discovered 2009 · Radial Velocity

A gas giant

13.40 Earth radii, Jupiter-class (Jupiter is 11.2). At only 674.0 Earth masses for that size, it must be substantially gas or volatile ices: puffy, not rocky.

The orbit

Its year, one full orbit, takes just 44.2 Earth days. The orbit is strongly stretched (eccentricity 0.47), so its distance from the star, and with it the climate, swings dramatically.

Temperature and starlight

Its equilibrium temperature (the airless-world estimate) is about 247 °C. Above water's boiling point. It receives 12.5 times the starlight Earth gets.

Its sun

Its star is Sun-like (5,441 K, G9 V; the Sun is 5,772 K). It shares the system with 1 other known planet.

How far is that, really?

At 132 light-years, tonight's light from this system left it around the year 1894. A Voyager-speed probe would need roughly 2,332,780 years to get there.

How we found it

It was found by the radial-velocity method: the planet's gravity swings its star in a small circle, and that wobble shows up as a rhythmic Doppler shift in the starlight. The wobble's size gives the planet's minimum mass. The discovery was announced in 2009 from La Silla Observatory.

Everything above is computed from the archive’s measured values for this planet. Where a quantity is missing, the statement is omitted rather than guessed.

About this record

The measured values come from the NASA Exoplanet Archive, and any missing value has not been determined yet; the Atlas never fills gaps with guesses. More standout worlds: Proxima b, TRAPPIST-1e, K2-18 b, 55 Cancri e, and the detection methods that found them all.

Sister planets around HD 147018