Email Print Share
January 28, 2016

Nearest bright 'hypervelocity star' found

An astrophysicist artist's conception of a hypervelocity star speeding away from the visible part of a spiral galaxy like our Milky Way and into the invisible halo of mysterious dark matter that surrounds the galaxy's visible portions. Zheng Zheng, an assistant professor of physics and astronomy at the University of Utah, and colleagues in the U.S. and China discovered the closest bright hypervelocity star yet found.

More about this image
Speeding at more than 1 million miles-per-hour, the bright hypervelocity star may provide clues about the supermassive black hole at the center of our Milky Way and the halo of mysterious dark matter surrounding the galaxy, astronomers say.

"The hypervelocity star tells us a lot about our galaxy -- especially its center and the dark matter halo," says Zheng. "We cant see the dark matter halo, but its gravity acts on the star. We gain insight from the stars trajectory and velocity, which are affected by gravity from different parts of our galaxy."

In the past decade, astronomers have found about 20 of these odd stars. Hypervelocity stars appear to be remaining pairs of binary stars that once orbited each other and got too close to the supermassive black hole at the galaxys center. Intense gravity from the black hole -- which has the mass of 4 million stars like our sun -- captures one star so it orbits the hole closely and slingshots the other on a trajectory headed beyond the galaxy.

Zheng and colleagues discovered the new hypervelocity star while conducting other research into stars with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope, located at the Xinglong Observing Station of the National Astronomical Observatories of China.

The study was funded by the National Science Foundation (grants AST 09-37523, PHY 08-22648 and AST 10-10039) and the National Development and Reform Commission of China.

To learn more, see the University of Utah news story Nearest bright 'hypervelocity star' found. (Date image taken: May 2015; date originally posted to NSF Multimedia Gallery: Jan. 28, 2016)

Credit: Ben Bromley, University of Utah

See other images like this on your iPhone or iPad download NSF Science Zone on the Apple App Store.

Images and other media in the National Science Foundation Multimedia Gallery are available for use in print and electronic material by NSF employees, members of the media, university staff, teachers and the general public. All media in the gallery are intended for personal, educational and nonprofit/non-commercial use only.

Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation.

Additional information about general usage can be found in Conditions.

Also Available:
Download the high-resolution JPG version of the image. (2.1 MB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.