Astronomers have discovered a unique binary system, ν Octantis, which seems to defy conventional expectations. The system consists of two stars gravitationally bound together, but unlike typical tight binaries, the planet is orbiting at a distance similar to Earth’s orbit around our Sun. However, this system takes it a step further with the planet rotating backward relative to its white dwarf companion.
At the center of this unusual system is a heavy star with a mass slightly heavier than our Sun. It is orbited by a smaller companion that has not been well-studied until now. The companion’s orbit is eccentric, ranging from 2-3 times the distance between Earth and the Sun. Despite initial attempts to detect additional objects in the system, detailed imaging revealed only two stars: the central heavy star and its white dwarf companion.
Further analysis suggests that the white dwarf is approximately half the mass of our Sun, supporting the idea of a low-mass companion. The unique characteristics of this binary system make it an exciting discovery for astronomers to study further.
Source: https://arstechnica.com/science/2025/05/planet-found-orbiting-backward-between-two-stars