Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Much faster than a speeding bullet, planets and stars escape the Milky Way

30.03.2012
Idan Ginsburg, a graduate student in Dartmouth's Department of Physics and Astronomy, studies some of the fastest moving objects in the cosmos.

When stars and their orbiting plants wander too close to the supermassive black hole at the center of the Milky Way, their encounter with the black hole's gravitational force can either capture them or eject them from the galaxy, like a slingshot, at millions of miles per hour.

Although their origin remains a mystery and although they are invisible, black holes found at galaxy centers make their presence known through the effects they have on their celestial surroundings. The Milky Way's black hole, a monster with a mass four million times that of the Sun, feeds on some of its neighbors and thrusts others out into the intergalactic void.

It's the expelled objects that "become hypervelocity planets and stars," say Ginsburg. "What we learn from these high-speed travelers has significance for our understanding of planetary formation and evolution near the central black hole."

Ginsburg, along with his doctoral adviser Professor Gary Wegner, and Harvard Professor Abraham Loeb are publishing a paper in the Monthly Notices of the Royal Astronomical Society. It describes how the team constructed computer simulations of these hypervelocity bodies as a means to understanding the dynamics involved. "The paper is a 'call to arms' for other astronomers to join the search," Ginsburg announces.

Born in Israel, Ginsburg came to the United States as a child and grew up as a Midwesterner. After high school in Lawrence, Kan., graduating from the University of Illinois at Urbana-Champaign, and studies at Harvard, Ginsburg came to Dartmouth almost five years ago.

For the origin of hypervelocity bodies, Ginsburg and his colleagues point to the close interaction of a binary star system—two stars orbiting a common center—with a massive black hole. The likely scenario is the black hole draws one of the pair into its gravitational well while simultaneously ejecting the other at 1.5 million miles per hour. More than 20 of these hypervelocity stars have been identified in the Milky Way.

"You can also have a lone hypervelocity planet, peeled away from its star and ejected from the black hole. The same mechanism that produces a hypervelocity star produces a hypervelocity planet," Ginsburg explains. "But because it is so small and traveling up to 30 million miles per hour, it cannot be seen. That doesn't mean they won't eventually be found, but currently it is beyond the limitations of our technology."

Ginsburg contends, however, that you could see a hypervelocity star ejected with planets still in tow. In this case, you might be able to see the planets as they cross in front of the star like an eclipse, appearing as a dip in its light curve. While the paper discusses the lone hypervelocity planets, it also draws attention to the planets rotating around the hypervelocity stars.

"That is something that we can detect now," Ginsburg says, "which I think makes it very interesting. … As of yet nobody has looked for these planets transiting hypervelocity stars. We are telling people in this paper that you should look for these."

Joseph Blumberg | EurekAlert!
Further information:
http://www.dartmouth.edu

More articles from Physics and Astronomy:

nachricht New NASA study improves search for habitable worlds
20.10.2017 | NASA/Goddard Space Flight Center

nachricht Physics boosts artificial intelligence methods
19.10.2017 | California Institute of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>