Published on : May 18, 2018
NASA announces the completion of the Legacy ExtraGalactic UV Survey (LEGUS) or, as the agency describes it, “the sharpest, most comprehensive ultraviolet-light survey of star-forming galaxies in the nearby universe.” The project captures a whopping 39 million hot blue stars and about 8,000 star clusters within a 60 million light year radius around Earth. The stars range from one to several billions years old, and are bunched together in groups ten times more massive than the largest ones seen in our Milky Way galaxy.
The researchers combined new Hubble observations with archival Hubble images for 50 star-forming spiral and dwarf galaxies in the local universe, offering a large and extensive resource for understanding the complexities of star formation and galaxy evolution.
The Wide Field Camera 3 and the Advanced Camera on Hubble were used to snap UV and visible pictures of the galaxies over a year. The scientists are hoping that they will reveal secrets into how the stars formation is impacted by its environment.
The results from the LEGUS survey will also come in handy when NASA launches the James Webb Space Telescope in 2020. It operates at longer wavelengths at orange and red visible light through to infra-red, so it can detect the glow of younger stars hidden and still swaddled in a cloak of gas and dust.
Aside from the data on these galaxies’ stars and star clusters, the LEGUS survey could provide important information about “the connection between star formation and the major structures, such as spiral arms, which make up a galaxy,” NASA points out.