Deep in the galaxy’s country side, far from the hustle and bustle of the crowded core, stars are in full bloom, according to recent images taken by NASA’s Spitzer Space Telescope.
“We sometimes call this flyover country,” Barbara Whitney, an astronomer from the University of Wisconsin who uses Spitzer to study young stars, said in a news release.
The images are part of the Galactic Legacy Infrared Mid-Plane Survey Eztraordinaire, or Glimpse 360, project, dedicated to mapping the celestial topography of the Milky Way that, once completed, will provide a 360-degree view of the galaxy plane to anyone with a computer. And while Spitzer and other telescopes like it have pieced together mosaics of the plane looking in the direction of the galaxy's center, or “downtown” region, the expanse farther out is much sparser and less charted.
As a result, as the project progresses, Whitney said, astronomers are “finding all sorts of new star formation in the lesser-known areas at the outer edges of the galaxy,”
Among Whitney and her team’s finds is an area near Canis Major home to more than 30 young stars still sprouting out jets of material, signifying an early stage in their lives.
All told, researchers have identified 163 regions containing these jets in the Glimpse 360 data, some of which live in packs and others preferring a life by themselves.
Robert Benjamin is the head of a team from the University of Wisconsin using Spitzer to more carefully pinpoint the distance to the galaxy’s hinterlands.
“With Spitzer, we can see out to the edge of the galaxy better than before,” Benjamin said. “We are hoping this will yield some new surprises.”
Their discoveries so far include, among other things, a distinct and rapid drop-off of red giants, a type of older star, toward the edges of the galaxy.
Using this and other information, the astronomers are mapping the structure of the warp in the galaxy’s disc.
Meanwhile, data from NASA’s Wide-field infrared Survey Explorer (WISE) is helping to fill in the areas Spitzer left out. WISE was designed to survey the entire sky twice in infrared light, completing the job in early 2011. On the other hand, Sptizer continues to probe the infrared sky in greater detail.
And nor are these two the final say: amateur stagazers have joined in by scouring images from earlier Glimpse data in search of cosmic bubbles indicating hot, massive stars. Called The Milky Way Project, it was volunteers who were the first to identify a structure in a star-forming region that later turned out to be the result of massive stars.
“This crowdsourcing approach really works,” said Charles Kerton of Iowa State University. “We are examining more of the hierarchical bubbles identified by the volunteers to understand the prevalence of triggered star formation in our galaxy.”
Ultimately, by piecing all this information together, scientists are beginning to canvas the Milky Way in greater detail than ever before, filling in blanks in outer regions where little is known.