Stellar pinwheels at our Galaxy's core

August 18, 2006

Astronomers have finally learned the identity of a mysterious "Quintuplet Cluster" of stars situated near the supermassive black hole at our galaxy's core: At least two of the objects are not individual stars, but binary pairs that live fast and die young, forming fiery pinwheels as they spin around one another.

A multinational team led by Peter Tuthill of the University of Sydney in Australia, used the extraordinary resolution of the 10-meter telescope at the W.M. Keck Observatory in Hawaii, to determine the nature of the enigmatic objects. They report their findings in the Aug. 18 issue of the journal Science.

Until these observations, researchers had not known whether the extremely red "cocoon" quintuplets were aging stars surrounded by shells of dust, or young stars accompanied by disks of bright gas. Neither hypothesis was convincing, and neither fully explained the enormous light output: Each quintuplet emits 10,000 to 100,000 times as much radiation as the Sun.

The new findings indicate the quintuplets are members of a rare class called "Wolf-Rayet colliding-wind binaries" -- massive, fast-burning star pairs that live only a few million years before exploding in terminal supernovae. By contrast, the Sun is about 5 billion years old and only middle-aged. The pinwheel effect is caused by the way each star's dusty mantle is affected by that of its partner, producing spiral plumes.

"The discovery of spiral plumes, the size of our entire solar system, has solved the enigma of the bright red stars in the Quintuplet Cluster located right next door (within 100 light-years) to the center of our Galaxy," says study co-author Andrea Ghez of the University of California, Los Angeles. "Within the astronomy world, there has been a surge of interest in these stars. Wolf-Rayets are very massive stars at the very end-point of their normal lives: they are the last stable phase before a supernova explosion. Massive binary systems such as these pinwheel stars will, in fact, explode three times: two explosions as each of the pair separately undergoes a core-collapse supernova, then a third explosion as the two fall into each other in an inspiral-merger event -- possibly in the quite-distant future."
-end-
The team also included researchers from the University of Michigan, the Jet Propulsion Laboratory at Caltech, Rochester Institute of Technology (RIT) and NASA's Goddard Space Flight Center. The research was funded by the Australian Research Council and the National Science Foundation's astronomy division.

For more information, see the RIT news release.

National Science Foundation

Related Supernova Articles from Brightsurf:

Scientists discover supernova that outshines all others
A supernova at least twice as bright and energetic, and likely much more massive than any yet recorded has been identified by an international team of astronomers, led by the University of Birmingham.

Supernova observation first of its kind using NASA satellite
Their research, detailed in the Monthly Notices of the Royal Astronomical Society, represents the first published findings about a supernova observed using TESS, and add new insights to long-held theories about the elements left behind after a white dwarf star explodes into a supernova.

Astronomers find possible elusive star behind supernova
Astronomers may have finally found a doomed star that seemed to have avoided detection before its explosive death.

Stellar thief is the surviving companion to a supernova
Hubble found the most compelling evidence that some supernovas originate in double-star systems.

Supernova may have 'burped' before exploding
Only by increasing the rate at which telescopes monitor the sky has it been possible to catch more Fast-Evolving Luminous Transients (FELTs) and begin to understand them.

An unusual white dwarf may be a supernova leftover
Astronomers have identified a white dwarf star in our galaxy that may be the leftover remains of a recently discovered type of supernova.

Researchers show how to make your own supernova
Researchers from the University of Oxford are using the largest, most intense lasers on the planet, to for the first time, show the general public how to recreate the effects of supernovae, in a laboratory.

The big star that couldn't become a supernova
For the first time in history, astronomers have been able to watch as a dying star was reborn as a black hole.

Seeing quadruple: Four images of the same supernova, a rare find
Galaxies bend light through an effect called gravitational lensing that helps astronomers peer deeper into the cosmos.

Explosive material: The making of a supernova
Pre-supernova stars may show signs of instability for months before the big explosion

Read More: Supernova News and Supernova Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.