In 1995, astronomers first discovered Gliese 229 B, a celestial object known as a brown dwarf or a "failed star." Its nature perplexed the scientific community due to its unexpectedly low brightness. After nearly 30 years, two independent research teams have finally unlocked the mystery, revealing that Gliese 229 B is actually not one, but two closely orbiting brown dwarfs.

A Dual Star Revelation

Brown dwarfs are unique astronomical bodies that possess too little mass for nuclear fusion like stars but are significantly heavier than planets. Since the discovery of Gliese 229 B, numerous other brown dwarfs have been found, even by amateur astronomers. Typically, the brightness of these objects aligns with their mass. However, Gliese 229 B defied expectations, remaining much dimmer than it should have been given its mass. Scientists have now uncovered that the error lay in the assumption that it was a single entity. Instead, Gliese 229 B consists of two brown dwarfs with masses 38 and 34 times that of Jupiter, which orbit each other every 12 days and complete an orbit around a small red star in 250 years. These are now officially named Gliese 229 Ba and Gliese 229 Bb.

Implications and New Questions

This discovery answers one mystery while raising others, particularly the origins of these celestial bodies. There are theories, but it remains unclear whether the formation process of these brown dwarf pairs resembles that of planet formation, suggesting the potential creation of binary exoplanets. The discovery implies many more such objects are waiting to be found, deepening our understanding of brown dwarfs.

For further insights, these findings are presented in the Nature journal and the Astrophysical Journal Letters.

This revelation reshapes our grasp of substellar astrophysics and hints at the complexity of celestial formations, encouraging future explorations into cosmic phenomena.

Original Source from heise online.