This is RCW 86, the remnant of a Type 1a supernova 8,000 light-years away. Studying Type 1a supernovae led to the discovery that the universe’s expansion is accelerating. An astonishing 2025 study called this discovery into question. But now, new research claims to have found flaws in the 2025 paper. Image via NASA/ CXC/ SAO/ ESA (X-ray)/ JPL-Caltech/ B. Williams (infrared). The Royal Astronomical Society originally published this article on Jun…