The astronomers at Indiana University discovered a faint blue galaxy called Leoncino or “little lion” in the Leo Minor constellation, about 30 million light-years away from Earth. According to them, the little lion could shed light about the birth of the universe since it contains the lowest level of metals, which suggests its make-up did not change drastically since the Big Bang.
“Finding the most metal-poor galaxy ever is exciting since it could help contribute to a quantitative test of the Big Bang,” says John Salzer. “There are relatively few ways to explore conditions at the birth of the universe, but low-metal galaxies are among the most promising.”
The study published on May 12 in the Astrophysical Journal states that heavy chemical elements other than hydrogen or helium are known as metals. The metals are produced by stars and spread through the galaxy when the stars explode as supernovae.
Leoncino contains just 1.3 percent the metallicity of the Sun, indicating that only a few star formations happened since its birth. It is about 1,000 light-years in diameter and consists of a few million stars, unlike the Milky Way, which is estimated to contain about 200 billion to 400 billion stars.
The little lion is named after its constellation and the Italian-born radio astronomer, Riccardo Giovanelli, the leader of the group that first saw the blue galaxy. Its blue color stems from the presence of newly formed hot stars. Nevertheless, the galaxy is dim, the lowest level of luminosity seen for this kind of cosmic object.
The research team will study the little lion further to gather more information about the galaxy. This time, they plan to use other telescopes, including the Hubble Space Telescope. “We’re eager to continue to explore this mysterious galaxy,” adds Salzer. “Low-metal-abundance galaxies are extremely rare, so we want to learn everything we can.”