California Institute of Technology | 2018 Dec 18
New visible and infrared observations of young star reveal clues about how it bulks up
Researchers have discovered a young star in the midst of a rare growth spurt—a dramatic phase of stellar evolution when matter swirling around a star falls onto the star, bulking up its mass. The star belongs to a class of fitful stars known as FU Ori's ...
"These FU Ori events are extremely important in our current understanding of the process of star formation but have remained almost mythical because they have been so difficult to observe," says Lynne Hillenbrand ... "This is actually the first time we've ever seen one of these events as it happens in both optical and infrared light, and these data have let us map the movement of material through the disk and onto the star."
The newfound star, called Gaia 17bpi, was first spotted by the European Space Agency's Gaia satellite ... members of the team then followed up and discovered that the star's brightening had been serendipitously captured in infrared light by NASA's asteroid-hunting NEOWISE satellite at the same time that Gaia saw it, as well as one-and-a-half-years earlier. ...
The new findings shine light on some of the longstanding mysteries surrounding the evolution of young stars. One unanswered question is: How does a star acquire all of its mass? Stars form from collapsing balls of gas and dust. With time, a disk of material forms around the star, and the star continues to siphon material from this disk. But, according to previous observations, stars do not pull material onto themselves fast enough to reach their final masses. ...
Gaia 17bpi: An FU Ori Type Outburst ~ Lynne A. Hillenbrand et al
- arXiv.org > astro-ph > arXiv:1812.06640 > 17 Dec 2018