Scientists looked at large star-formation galaxies to measure radiation leaks and gain insight into the early evolution of the universe.
The NASA-funded research team used the radiation links to identify star-forming galaxies that contained holes in its gas cover, Johns Hopkins University reported.
This cover is made up of dense, chilly gas that stretches across the sky "like a blanket." For decades scientists have been on the hunt to find a "holey" galaxy that would allow them to study how star-produced radiation is involved in the ionization process.
"It's like the ozone layer, but in reverse," said Sanchayeeta Borthakur, an assistant research scientist in the university's Department of Physics and Astronomy. "The ozone layer protects us from the sun's radiation but we want the gas cover the other way around. The star-forming regions in galaxies are covered with cold gases, so the radiation cannot come out. If we can find out how the radiation gets out of the galaxy, we can learn what mechanisms ionized the universe."
Reionization is central to the birth of the universe's first stars. Directly after the Big Bang the universe started to expand and cool, several hundred thousand years later free proton and electron particles started to connect with each other and form neutral hydrogen atoms. This neutral gas eventually collapsed into the universe's first stars and galaxies.
The researchers looked at observation with the Cosmic Origin Spectrograph aboard the Hubble Space Telescope, the team finally located the perfect galaxy to study. The team credits "a combination of unusually strong winds, intense radiation and a massive, highly star-forming galaxy" for the validity of the indicator, Johns Hopkins reported. The method can effectively determine the amount of holes in a galaxy as well as what gas is present.
"The confirmation of the indicator is key," Borthakur said. "The implications are now people can use this indicator to study distant galaxies at longer wavelengths."
The findings were published Oct. 9 in the journal Science.
