Astronomers announced the discovery of IRAS 04125+2902 b, an exoplanet estimated to be only three million years old. The object, also nicknamed TIDYE-1b, was identified by University of North Carolina at Chapel Hill graduate student Madyson Barber using observations from NASA’s Transiting Exoplanet Survey Satellite.
TESS repeatedly measures the brightness of stars. Barber found small, regular dips in the light from the star IRAS 04125+2902, the pattern expected when an orbiting planet passes between its star and the telescope. The resulting paper, published in Nature, describes the object as the youngest transiting planet known at the time. The next-youngest known example was thought to be about 10 million years old.
The planet completes an orbit every 8.83 days. Researchers estimated its radius at about 10.7 times that of Earth and placed an upper limit on its mass at roughly 30% of Jupiter’s. Barber cautioned that the team had 95% confidence in that upper-limit measurement and suspected the planet’s actual mass could be substantially lower. The estimate came from radial-velocity observations that detect small movements of the host star caused by an orbiting companion.
The star lies about 160 parsecs, or 522 light-years, from Earth and is approximately the same age as the planet. Its surrounding material has an unusual arrangement: the outer protoplanetary disk is misaligned, while the inner disk is depleted. That geometry helped make the transit visible. A disk aligned with both the star’s rotation and the planet’s orbit could otherwise have obscured the star from view.
At three million years, TIDYE-1b is extremely young compared with Earth, which is about 4.5 billion years old. Astronomers have relatively few transiting systems at such an early stage, limiting their ability to compare how planets form and change. The team said the object might represent a precursor to the super-Earths and sub-Neptunes commonly found around mature main-sequence stars.
Important questions remain unresolved. The available measurements do not precisely determine the planet’s mass or fully describe its composition and evolution. Yet its proximity, age and unusual disk configuration make the system a useful target for follow-up work. By studying more young transiting worlds, researchers hope to build a clearer account of planetary formation and place the early history of the Solar System in a broader context. The discovery also shows why disk geometry matters to detection: astronomers could see the recurring transit because the depleted and tilted material did not block their line of sight to the young star. during repeated observations.
