40 Eridani A is a main-sequence dwarf of spectral type K1, 40 Eridani B is a 9th magnitude white dwarf of spectral type DA4, and 40 Eridani C is an 11th magnitude red dwarf flare star of spectral type M4.5e. Credit: IAU/Sky and Telescope Magazine. The two most recent determinations are from Koester & Weidemann (1991) and Bergeron, Saffer, & Liebert (1992) . In this situation, the stars release energy when spiralling into each other, and this energy carries away material from the outer layers, allowing the formation of a lower mass white dwarf with a helium core. It is known that 40 Eridani is the intended home star of the Vulcans. The planet is officially known as 40 Eridani b, but from now on I will refer to it as rVulcan ("real vulcan.") The distance between Eridani A and B is 400 astronomical units . When component B was a main-sequence star, it is thought to have been the most massive member of the system, but ejected most of its mass before it became a white dwarf. It is a trinary star system 16.26 lightyears away from the Earth, and recently, a super-earth has been discovered orbiting the primary orange dwarf star 40 Eridani A. the radius of 40 eridani b and its uncertainty The radius of 40 Eri B has been determined by several investigators using model atmosphere calculations. 40 Eridani C: The tertiary star was classified as a M4V star with an absolute magnitude of 12.3. 40 Eridani A is located in visible on a clear night in the southern Eridanus constellation. So assuming the mass for 40 Eridani B was correct, it would have to be a helium-core white dwarf resulting from a binary-star merger. 40 Eridani B: The secondary star was classified as a AVII star with an absolute magnitude of 11.2.