51 Eridani b

51 Eridani b (aka 51 Eri b) is an extra-solar planet discovered through direct imaging in 2014 with the Gemini Planet Imager. It orbits about 11 AU from F-type star, 51 Eridani. As a directly-imaged object, data from observing it is useful in modeling apparently-similar objects orbiting closer to their hosts. Its effective temperature derived through spectroscopy is 700 K. The star's age is estimated as around 20 million years, suggesting a similar age for the planet, constraining it to be no more than that. Models of such a planet that include clouds in its atmosphere suggest a mass of on the order of 2 Jupiter masses is plausible.

• Host star: 51 Eridani (51 Eri).
• Discovery: by direct imaging in 2014.
• 96 ly - distance.
• 11 AU - orbital radius (semi-major axis).
• 0.49 - eccentricity.
• ~10,000 days - orbital period.
• 1.1 - radius in Jupiter radii.
• 2.6 - Jupiter masses.
• 700 K - predicted temperature.