NASA scientists and European researchers say the agency's Spitzer Space Telescope has detected cosmic clumps of gas so dark and dense they create the darkest shadows in our galaxy.
The inky areas are a portion of a giant cloud of particles and gas expected to condense eventually into what are called O-type stars among the biggest and brightest stars found throughout the observable universe, NASA and the University of Zurich announced.
The shadows that are cast by the dark clumps against their background are helping astrophysicists measure the overall mass and structure of the giant gas cloud, located around 16,000 light-years from Earth.
Those measurements suggest the gas cloud is likely to end up creating a cluster of young stars that will be among the biggest in the Milky Way galaxy, they say.
The formation process of giant O-type stars, which have major effects on local cosmic environment and also seed the galaxy with the heavier elements necessary for life, has long puzzled astronomers.
"The map of the structure of the cloud and its dense cores we have made in this study reveals a lot of fine details about the massive star and star cluster formation process," lead study author Michael Butler, a postdoctoral researcher at Switzerland's University of Zurich, says.
Spitzer observations at infra-red wavelengths have allowed the researchers to create a map of the cloud which shows it has a mass equal to 7,000 stars of our sun's size packed into a relatively small area just 50 light-years across, they reported in The Astrophysical Journal Letters.
While most of the universe's stars, probably including our sun, are believed to form in these sorts of environments as groups of low-mass stars that are common and therefore well-studied, clusters such as the one in the current study expected to give birth to stars of higher mass are distant and scarce, making them more difficult to investigate, the researchers said.
"In this rare kind of cloud, Spitzer has provided us with an important picture of massive star cluster formation caught in its earliest, embryonic stages," study co-author Jonathan Tan of the University of Florida says.
O-type stars will shine with an intense blue-white light, are at a minimum 16 times as massive as our sun, and have short lives, exploding as supernovas to forge the heavier elements that can create planets and life.
