Michael Werner on dusty disks’ planet-forming clues
It has been a century or more that astronomers have had the picture of solar systems forming in great disks of dust around young stars. In our time, astronomers are able to directly study these star-forming disks.
With his colleagues, Michael Werner takes infrared images of young stars using NASA’s Spitzer Space Telescope.
Michael Werner: We know now that when stars form, they collapse out of clouds of dust and gas in the interstellar medium. And an inevitable part of that formation process as the star collapses is the formation of a disk, which orbits the star.
Werner told EarthSky that as a star forms, gravity pulls in the surrounding gas and dust. Like a spinning figure skater tucking in her arms, the star then spins faster.
Michael Werner: And, eventually that situation can only be resolved, from the star’s point of view, by leaving some material behind, which it does in the form of this disk. . . . And it’s in these disks that are quite common around young stars that we feel that planets and planetary systems like our own solar system eventually form.
No one knows how many young stars have disks. But Werner cited one study showing them around up to 75% of stars found in some star clusters in and around the plane of our own Milky Way galaxy.
Astronomers are still researching the conditions that favor planets such as Earth to form and survive in these disks around stars.
Thanks today to Research Corporation, a foundation for the advancement of science.
Our thanks to:
Spitzer Space Telescope
Jet Propulsion Laboratory