82 G. Eridani d

A limitation of this method is that only a lower bound value in the mass can be obtained, assuming the orbital inclination relative to Earth is a right angle.

This mass suggests the planet is likely a super-Earth, but does not rule out the possbility that it is a mini-Neptune, with no solid surface and a thick hydrogen/helium atmosphere, inhospitable to life.

The true radius of the planet remains unknown, but estimates suggest if it is terrestrial it could be 1.7 R🜨 or so, and if it has a composition rich in volatiles it could be larger than 2.1 R🜨.

It is located at an average orbital distance of 1.35 AU (202×10^6 km), which would make it within the habitable zone (HZ),[1] a region where water can exist in a liquid state.

At its longest separation from 82 G. Eridani, the apoastron, it orbits beyond the habitable zone, and the irradiaton received decreases by a factor of 10 compared to periastron.

[2] The planet was confirmed in a follow-up study by N. Nari et al., which was published on October 15, 2024, about a year after the initial detection, also in the journal Astronomy and Astrophysics.

[14] The luminosity class "V" classifies 82 G. Eridani as a main sequence star fusing atoms of hydrogen into helium at its core.

It irradiates 60% of the solar luminosity from its photosphere[1] at an effective temperature of 5,470 K (5,200 °C),[15] giving it a yellow-white hue typical of late G-type stars.

[16] It is a high-velocity star—it is moving quickly compared to the average—and hence is a member of Population II, generally older stars whose motions take them well outside the plane of the Milky Way.