宇宙最大地图或解开暗能量之谜

A FIVE-YEAR survey of the sky that has captured more than 47 million galaxies and quasars is now complete. The data could help solve the mystery of an apparent weakening of dark energy, which threatens to upend our standard model of the cosmos. The Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory in Arizona has been scanning the sky since 2021. Researchers expected its survey to gather data on 34 million galaxies and quasars, but DESI surprised them with its efficiency. Because of the vast distances involved, some of these extremely faint galaxies have been observed from just 100 to 200 photons. …