Researchers from the National Astronomical Observatories of the Chinese Academy of Sciences identified the pulsar J0435+3233 as part of a rare proto-triple star system. The discovery was published in The Astrophysical Journal Letters on October 9, 2026.
The pulsar, first detected by the FAST telescope in June 2020, has a rotation period of 3.2 milliseconds. Five years of monitoring revealed it orbits a white dwarf every 8 days. The system also includes a sun-like star orbiting the pair every 73.5 years.
This system is unique because the third star is still evolving. Scientists believe the three stars formed from the same cloud. Eventually, the third star will fade, leaving a stable system of one pulsar and two white dwarfs.
The Chinese team achieved higher precision in determining orbital parameters compared to an independent European research group. They utilized data from the FAST radio telescope, Gaia, 2MASS, PanSTARRS, and the Fermi satellite.
This discovery provides a platform for testing fundamental gravitational theories, such as the strong equivalence principle. It serves as a sample for studying the complex evolution of triple-star systems.
