The Milky Way ate another galaxy. Scientists say they’ve found the scraps | CNN

An unusual collection of stars may represent the remnants of a dwarf galaxy that the Milky Way devoured about 10 billion years ago. Astronomers have dubbed the ancient galaxy Loki, after the Norse god of mischief. The finding could change the current understanding of how the Milky Way evolved in the distant past. The vast Milky Way spans about 100,000 light-years and contains anywhere between 100 billion and 400 billion stars, according to NASA. A light-year is the distance light travels in one year, which is 5.88 trillion miles (9.46 trillion kilometers). Our home galaxy wasn’t always such a cosmic giant. It grew over time starting about 12 billion years ago by merging with a multitude of dwarf galaxies. But the original size and mass of the Milky Way remain an open question — driving scientists to search for evidence of the galaxies it consumed to determine its history and evolution. To identify those missing puzzle pieces, astronomers have now zeroed in on a cluster of metal-lacking stars detected oddly close to the galactic disk, according to a study published in May in the journal Monthly Notices of the Royal Astronomical Society. Astronomers capture the most detailed i