Data from the Gemini North telescope on Mauna Kea played a role in providing astronomers an illuminating look into a young, distant galaxy. Data from the Gemini North telescope on Mauna Kea played a role in providing astronomers an illuminating
Data from the Gemini North telescope on Mauna Kea played a role in providing astronomers an illuminating look into a young, distant galaxy.
A Harvard-based research team used light from a supernova, the explosion of a dying star, to learn about a galaxy 9.5 billion light years away. University of Hawaii at Manoa’s Institute for Astronomy professor John Tonry likened what the scientists were able to do to looking into the ocean from above the surface.
Without the light from the supernova, astronomers found their stargazing a little like looking at the ocean at night — they couldn’t see into the galaxy. With the light, it was more like looking at the ocean during the day, with sunlight penetrating the water and reflecting off the sand, giving observers a glimpse at what is in the water, Tonry said.
“By having a strong light bulb, this supernova, we can get a sense of what’s going on in the galaxy,” Tonry said.
Looking so far back in time helps scientists uncover more information about how our own galaxy formed, and how the gases from the Big Bang eventually led to planets, “people and wedding rings,” Tonry said.
Lead researcher Edo Berger, of Harvard-Smithsonian Center for Astrophysics, said the findings show the “enormous potential of using the most luminous supernovae to study the early universe. Ultimately it will help us understand how galaxies like our Milky Way came to be.”
The study was published in the most recent edition of “The Astrophysics Journal.” This is the first direct demonstration of the technique, which scientists said could be used to look up to 90 percent of the way back to the Big Bang.
Images from Pan-STARRS1 survey telescope on Haleakala helped with the discovery of the dying star, scientists said. Follow-up studies using Gemini and the Multiple Mirror Telescope in Arizona provided the data the team used to learn more about the gas of the distant galaxy’s environment, scientists said. What scientists found was evidence of iron and magnesium in the distant galaxy, which contained a young population of stars about 15 million to 45 million years old.
Alicia Soderberg, of Harvard University, explained the advantages of studying galaxies in this way.
“The beauty of studying distant galaxies using ultraluminous supernovae as a tool is that it eliminates the need for satellites and offers more time for study,”she said. “A typical ultraluminous supernova can take several weeks to fade away.”
Scientists generally either look directly for chemical elements leaving bright imprints on a galaxy’s spectrum of light, search indirectly for “dark signatures in the spectrum of an even more distant quasar, which reveals chemical elements in an intervening system that have absorbed light along our line of sight,” or, more recently, seek out dark absorption imprints in the afterglow of “gamma-ray bursts,” Gemini officials said.
Officials noted two drawbacks to using the latter method.
“These brief flashes are the brightest and most energetic explosions in the universe, but they fade away within hours,” Gemini officials said. “The method is also limited by the need for expensive Earth-orbiting satellites to first detect and pinpoint a burst’s location with precision before astronomers can make ground-based studies.”
