05/09/2023
Astronomers have found a new way to detect one of the oldest features of our universe.
These Baryon Acoustic Oscillations, or BAO, are subtle wrinkles that flowed through cosmic matter during the first 380,000 years of the universe's existence. Today, they are popular subjects in space science because they're one of the very few hints of the Big Bang that can still be traced — and importantly, astronomers can use the presence of BAOs to measure cosmic distances as well as the rate at which the universe is expanding.
While astronomers have historically focused on galaxy clusters to observe these cosmically imprinted waves, a new study aims to sniff out some overlooked waves by looking at galaxy shapes and orientations rather than just clusters as a whole. These features, the study researchers write, can offer a "promising cosmological probe" yet have been ignored so far.