Featured Research

from universities, journals, and other organizations

Magnetic jet shows how stars begin their final transformation

Date:
September 16, 2013
Source:
Royal Astronomical Society (RAS)
Summary:
Astronomers have for the first time found a jet of high-energy particles emanating from a dying star. The discovery is a crucial step in explaining how some of the most beautiful objects in space are formed -- and what happens when stars like the sun reach the end of their lives.

Two older objects, the Calabash nebula (a proto-planetary nebula) and M 2-9 (a young planetary nebula) show how IRAS 15445-5449 (left panel) may evolve in the future. The white bar indicates 0.5 light year.
Credit: E. Lagadec/ESO/A. Pérez Sánchez; NASA/ESA & Valentin Bujarrabal; B. Balick, V. Icke, G. Mellema and NASA/ESA

An international team of astronomers has for the first time found a jet of high-energy particles emanating from a dying star. The discovery, by a collaboration of scientists from Sweden, Germany and Australia, is a crucial step in explaining how some of the most beautiful objects in space are formed -- and what happens when stars like the sun reach the end of their lives.

The researchers publish their results in the journal Monthly Notices of the Royal Astronomical Society.

At the end of their lives, stars like the sun transform into some of the most beautiful objects in space: amazing symmetric clouds of gas called planetary nebulae. But how planetary nebulae get their strange shapes has long been a mystery to astronomers.

Scientists at Chalmers University of Technology in Sweden have together with colleagues from Germany and Australia discovered what could be the key to the answer: a high-speed, magnetic jet from a dying star.

Using the CSIRO Australia Telescope Compact Array, an array of six 22-metre radio telescopes in New South Wales, Australia, they studied a star at the end of its life. The star, known as IRAS 15445−5449, is in the process of becoming a planetary nebula, and lies 23,000 light years away in the southern constellation Triangulum Australe (the Southern Triangle).

"In our data we found the clear signature of a narrow and extremely energetic jet of a type which has never been seen before in an old, sun-like star," says Andrés Pérez Sánchez, graduate student in astronomy at Bonn University, who led the study.

The strength of the radio waves of different frequencies from the star match the expected signature for a jet of high-energy particles which are, thanks to strong magnetic fields, accelerated up to speeds close to the speed of light. Similar jets have been seen in many other types of astronomical object, from newborn stars to supermassive black holes.

"What we're seeing is a powerful jet of particles spiralling through a strong magnetic field," says Wouter Vlemmings, astronomer at Onsala Space Observatory, Chalmers. "Its brightness indicates that it's in the process of creating a symmetric nebula around the star."

Right now the star is going through a short but dramatic phase in its development, the scientists believe.

"The radio signal from the jet varies in a way that means that it may only last a few decades. Over the course of just a few hundred years the jet can determine how the nebula will look when it finally gets lit up by the star," says team member Jessica Chapman, astronomer at CSIRO in Sydney, Australia.

The scientists don't yet know enough, though, to say whether our sun will create a jet when it dies. "The star may have an unseen companion -- another star or large planet -- that helps create the jet. With the help of other front-line radio telescopes, like ALMA, and future facilities like the Square Kilometre Array (SKA), we'll be able to find out just which stars create jets like this one, and how they do it," says Andrés Pérez Sánchez.


Story Source:

The above story is based on materials provided by Royal Astronomical Society (RAS). Note: Materials may be edited for content and length.


Journal Reference:

  1. A. F. Pérez-Sánchez, W. H. T. Vlemmings, D. Tafoya, and J. M. Chapman. A synchrotron jet from a post-asymptotic giant branch star. MNRAS, September 15, 2013 DOI: 10.1093/mnrasl/slt117

Cite This Page:

Royal Astronomical Society (RAS). "Magnetic jet shows how stars begin their final transformation." ScienceDaily. ScienceDaily, 16 September 2013. <www.sciencedaily.com/releases/2013/09/130916090836.htm>.
Royal Astronomical Society (RAS). (2013, September 16). Magnetic jet shows how stars begin their final transformation. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2013/09/130916090836.htm
Royal Astronomical Society (RAS). "Magnetic jet shows how stars begin their final transformation." ScienceDaily. www.sciencedaily.com/releases/2013/09/130916090836.htm (accessed July 31, 2014).

Share This




More Space & Time News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Supply Ship Takes Off for International Space Station

Supply Ship Takes Off for International Space Station

AFP (July 30, 2014) — The European Space Agency's fifth Automated Transfer Vehicle (ATV-5) is takes off to the International Space Station on an Ariane 5 rocket from French Guiana. Duration: 00:34 Video provided by AFP
Powered by NewsLook.com
Raw: Rocket Launches Into Space With Cargo Ship

Raw: Rocket Launches Into Space With Cargo Ship

AP (July 30, 2014) — Arianespace launched a rocket Tuesday from French Guiana carrying a robotic cargo ship to deliver provisions to the International Space Station. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) — Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com
Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) — The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:  

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile iPhone Android Web
    Follow Facebook Twitter Google+
    Subscribe RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins