Subscribe free to our newsletters via your
. 24/7 Space News .


Subscribe free to our newsletters via your




















STELLAR CHEMISTRY
Strong magnetic fields in the cores of many stars
by Staff Writers
Santa Barbara CA (SPX) Jan 05, 2016


Internal magnetic fields of red giants are up to 10 million times stronger than the Earth's. Image courtesy UCSB. For a larger version of this image please go here.

Using a recently developed technique to detect magnetic fields inside stars, a group of astronomers - including Matteo Cantiello and Lars Bildsten from UC Santa Barbara's Kavli Institute for Theoretical Physics (KITP) - has discovered that strong magnetic fields are very common in stars. The group's findings appear in the journal Nature.

"We have applied a novel theoretical idea that we developed just a few months ago to thousands of stars and the results are just extraordinary," said Cantiello, a specialist in stellar astrophysics at KITP.

Previously, only a very small percentage of stars were known to have strong magnetic fields. Therefore, current scientific models of how stars evolve do not include magnetic fields as a fundamental component.

"Such fields have simply been regarded as insignificant for our general understanding of stellar evolution," said lead author Dennis Stello, an astrophysicist at the University of Sydney in Australia. "Our result clearly shows this assumption needs to be revisited because we found that up to 60 percent of stars host strong fields."

Until now, astronomers have been unable to detect these magnetic fields because such fields hide deep in the stellar interior, out of sight from conventional observation methods that measure only the surface properties of stars. The research team turned to asteroseismology, a technique that probes beyond the stellar surface, to determine the presence of very strong magnetic fields near the stellar core.

"The stellar core is the region where the star produces most of its energy through thermonuclear reactions," Cantiello explained. "So the field is likely to have important effects on how stars evolve since it can alter the physical processes that take place in the core."

Most stars - like the sun - are subject to continuous oscillations. "Their interior is essentially ringing like a bell," noted co-author Jim Fuller, a postdoctoral scholar from the California Institute of Technology in Pasadena. "And like a bell or a musical instrument, the sound produced reveals physical properties, such as size, temperature and what they are made of."

The researchers used very precise data from NASA's Kepler space telescope to measure tiny brightness variations caused by the ringing sound inside thousands of stars. They found that certain oscillation frequencies were missing in 60 percent of the stars due to suppression by strong magnetic fields in the stellar cores.

"It's like having a trumpet that doesn't sound normal because something is hiding inside it, altering the sound it produces," Stello said.

This magnetic suppression effect had previously been seen in only a few dozen stars. However, the new analysis of the full data set from Kepler revealed that this effect is prevalent in stars that are only slightly more massive than the sun.

According to Cantiello, such intermediate mass stars are hotter and more luminous, and their cores are stirred by convection. "We believe that the magnetic field is created by this 'boiling' sequence and stored inside the star for the remaining evolutionary phase. Astrophysicists previously have suggested this but it was very speculative; now it seems clear that this is the case," he said.

"This is a very important result that will enable scientists to test more directly current theories for how magnetic fields form and evolve in stellar interiors," said co-author Bildsten, the director of KITP. "When a star dies, the presence of strong magnetic fields can have a profound impact, possibly resulting in some of the brightest explosions in the universe."

This research could potentially lead to a better general understanding of stellar magnetic dynamos, including the one controlling the sun's 11-year sunspot cycle, which is known to affect communication systems and cloud cover on Earth.

"So far, the study of stellar magnetic dynamos principally relied on computer simulations, which now can be tested using these new exciting observations," said Fuller.

.


Related Links
University of California - Santa Barbara
Stellar Chemistry, The Universe And All Within It






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
STELLAR CHEMISTRY
Astronomers look to high-mass stars for clues to the origins of life
Tokyo (UPI) Dec 29, 2015
New research out of Japan promises to bolster the search for the origins of life in the distant cosmos. The chemical building blocks of biological life were born in the fiery formations of stars. But which stars, and where and how? Astrophysicist Takeshi Sakai believes large stars born in the stellar clusters 10,000 light-years away hold clues to the origins of life. But studying ... read more


STELLAR CHEMISTRY
Russia Postpones Plans on Extensive Moon Exploration Until 2025

South Korea to launch lunar exploration in 2016, land by 2020

Death rumors of Russian lunar program 'greatly exaggerated' - Deputy PM

Rare full moon on Christmas Day

STELLAR CHEMISTRY
Boulders on a Martian Landslide

NASA suspends March launch of InSight mission to Mars

University researchers test prototype spacesuits at Kennedy

Marshall: Advancing the technology for NASA's Journey to Mars

STELLAR CHEMISTRY
Congress to NASA: Hurry up on that 'habitation augmentation module'

NASA Reaches New Heights

Gadgets get smarter, friendlier at CES show

Astronauts Tour Future White Room, Crew Access Tower

STELLAR CHEMISTRY
China launches HD earth observation satellite

Chinese rover analyzes moon rocks: First new 'ground truth' in 40 years

Agreement with Chinese Space Tech Lab Will Advance Exploration Goals

China launches new communication satellite

STELLAR CHEMISTRY
NASA Delivers New Video Experience On ISS

British astronaut dials wrong number on Xmas call from space

Space Station Receives New Space Tool to Help Locate Ammonia Leaks

Two whacks is all it takes for spacewalk repair

STELLAR CHEMISTRY
Russian Space Forces launched 21 spacecraft in 2015

Russian Proton-M Carrier Rocket With Express-AMU1 Satellite Launched

45th Space Wing launches ORBCOMM; historically lands first stage booster

SpaceX rocket landing opens 'new door' to space travel

STELLAR CHEMISTRY
Nearby star hosts closest alien planet in the 'habitable zone'

ALMA reveals planetary construction sites

Monster planet is 'dancing with the stars'

Exoplanets Water Mystery Solved

STELLAR CHEMISTRY
Watch: Six decades worth of space junk orbit Earth

Infrared encoding of images with metasurfaces

Tooth fillings of the future may incorporate bioactive glass

Transition metal catalyst prompts 'conjunctive' cross-coupling reaction




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News








The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.