Astronomers Nab Runaway Star
This image of the 30 Doradus nebula, a rambunctious stellar nursery, and the enlarged inset photo show a heavyweight star that may have been kicked out of its home by a pair of heftier siblings.
In the inset image at right, an arrow points to the stellar runaway and a dashed arrow to its presumed direction of motion. The image was taken by the Wide Field and Planetary Camera 2 (WFPC2) aboard NASA's Hubble Space Telescope. The heavyweight star, called 30 Dor #016, is 90 times more massive than the Sun and is traveling at more than 250,000 miles an hour.
In the wider view of 30 Doradus, the homeless star, located on the outskirts of the nebula, is centered within a white box. The box shows Hubble's field of view. The image was taken by the European Southern Observatory's (ESO) Wide Field Imager at the 2.2-meter telescope on La Silla, Chile.
The young star, only 1 million to 2 million years old, may have traveled about 375 light-years from its suspected home in R136, the bright star cluster marked by a circle. Nestled in the core of 30 Doradus, R136 is one of the most massive young star clusters in nearby galaxies, containing several stars topping 100 solar masses each. 30 Doradus, also called the Tarantula Nebula, resides roughly 170,000 light-years from Earth, in the Large Magellanic Cloud.
Instruments at three observatories, including Hubble's WFPC2 and recently installed Cosmic Origins Spectrograph, have provided tantalizing clues that the star was ejected from R136.
In the ESO and WFPC2 images, hot stars are represented by the color blue. Hydrogen is in red and oxygen in green. Radiation from the runaway star is making the nebula glow.
The Hubble image was taken on June 30, 1995; the ESO image was released in December 2006.
The runaway star research team consists of C. Evans, V. Henault-Brunet, and W. Taylor (Royal Observatory Edinburgh); N. Walborn and D. Massa (Space Telescope Science Institute, Baltimore); D. Lennon (European Space Agency/Space Telescope Science Institute); P. Crowther (University of Sheffield, UK); I. Howarth (University College London); H. Sana (ESO/University of Amsterdam); and J. van Loon (Keele University, UK).
Credit for ESO Image: ESO;
Acknowledgment: J. Alves (Calar Alto, Spain), and B. Vandame and Y. Beletski (ESO). Processing by B. Fosbury (ST-ECF).