Astronomers have built a stunning atlas of 400,000 galaxies in the Milky Way‘s cosmic neighborhood. The atlas contains comprehensive photographs of countless galaxies that are not just available to astronomers but are also freely accessible to the general public online. The Siena Galaxy Atlas (SGA) is a digital atlas that was designed to learn more about our universe by exploring various known galaxies. The digital atlas of galaxies was constructed using data from three astronomical surveys conducted at Cerro Tololo Inter-American Observatory (CTIO) and Kitt Peak National Observatory (KPNO) between 2014 and 2017. These surveys are referred to together as the DESI Legacy Surveys.
Nearby large galaxies are important because we can study them in more detail than any other galaxies in the universe
Cosmic atlases assist astronomers in detecting patterns that aid in categorizing new findings, such as stars that quickly flare and then fade (dubbed ‘transients’). These atlases also assist astronomers in determining which objects are candidates for detailed follow-up studies. These databases must also be continually updated in order to stay up with new findings, especially in this day and age when telescope technology is rapidly improving. In this way, the SGA atlas represents the pinnacle of precision. The SGA promises to be a gold mine of galactic data for scientists interested in anything from galaxies’ births and evolutions to the distribution of dark matter and the propagation of gravitational waves through space.
“Nearby large galaxies are important because we can study them in more detail than any other galaxies in the universe; they are our cosmic neighbours,” John Moustakas, SGA project leader and a physics professor at Siena College, said in a statement. “Not only are they strikingly beautiful, but they also hold the key to understanding how galaxies form and evolve, including our very own Milky Way galaxy.”
Unlike previous atlases, which depended on archaic equipment and photographic plates, the SGA is reliant on cutting-edge digital imagery captured by modern technology. What actually distinguishes SGA is the precision of data. It boasts of having the most precise data because it is based on photos acquired using highly sensitive devices. It is also the first cosmic atlas to include galaxies’ light profiles, which are curves that depict how the brightness of a galaxy fluctuates from brightest to dimmest.