Astronomers found two dead stars orbiting each other so fast that a whole 'year' goes by in just 27 minutes.
March 23, 2026
Original Paper
Expected evolution of the binary system ATLAS J1138-5139
arXiv · 2603.19572
The Takeaway
These two burnt-out stars, known as white dwarfs, are packed so tightly together that they are gradually spiraling toward a catastrophic collision. This system is one of the shortest-period orbits ever found and is expected to eventually end in a massive supernova explosion visible across the universe.
From the abstract
ATLAS J1138-5139 is a newly detected ultra-compact double white dwarf (DWD) system which is composed of a $1.02\,M_{\odot}$ carbon-oxygen white dwarf (CO WD) and a $0.24\,M_{\odot}$ helium (He) WD with an orbital period of about 27.68 min, making it one of the shortest-period DWD systems known. The future evolution and final fate of this system remain unexplored. In this work, we investigate the evolution of ATLAS J1138-5139 with the one-dimensional stellar evolution code Modules for Experiments