Astronomers have used new, high-frequency capabilities of the National Science Foundation’s Robert C. Byrd Green Bank Telescope, or GBT, to capture secrets of a starburst galaxy, called M82, in the Milky Way’s neighborhood.
According to the scientists, new data about M82 highlight streamers of material fleeing the disk of the galaxy, and concentrations of dense molecular gas surrounding pockets of intense star formation. M82 is located approximately 12 million light years away in the constellation Ursa Major, which is a classic example of a starburst galaxy that can produce new stars tens to hundreds-of-times faster than the Milky Way.
“With this new vision, we were able to look at M82 to explore how the distribution of molecular gas in the galaxy corresponded to areas of intense star formation,” Amanda Kepley of the National Radio Astronomy Observatory (NRAO) in Green Bank, W. Va., and the lead author of a paper accepted for publication in the Astrophysical Journal Letters, said in a statement. “Having this new capability may help us understand why stars form where they do.”
According to scientists, M82’s relative closeness helped the GBT target the galaxy. The new telescope’s “W-Band” receiver can detect the millimeter wavelength light that is emitted by molecular gas -- a capability that makes it the world’s largest single-dish, millimeter-wave telescope.
Although dense molecular gas is connected to areas of star formation, the link is poorly understood and this relationship may be different in different types of galaxies. However, astronomers hope to better understand this complex interplay by creating wide-angle maps of the gas in galaxies.
According to scientists, with its new W-Band receiver, the GBT was able to capture highly sensitive, wide-angle images of these gases in and around M82.
“The GBT data clearly show billowing concentrations of dense molecular gas huddled around areas that are undergoing bursts of intense star formation,” Kepley said. “They also reveal giant outflows of ionized gas fleeing the disk of the galaxy. These outflows are driven by star formation deep within the galaxy.”
Astronomers expect that this capability of the GBT will help them quickly survey entire galaxies and different regions of the galaxies in future observations.