Featured Research

from universities, journals, and other organizations

Shrinking Giants, Exploding Dwarves

Date:
August 30, 2007
Source:
Weizmann Institute of Science
Summary:
New, detailed observations of a supernova show evidence that a white dwarf star "fed" off a red giant to gain the critical mass needed for explosion. When white dwarf stars explode, they leave behind a rapidly expanding cloud of 'stardust' known as a Type Ia supernova. These exploding events, which shine billions of times brighter than our sun, are all presumed to be extremely similar, and thus have been used extensively as cosmological reference beacons to trace distance and the evolution of the Universe. Astronomers have now -- for the first time ever -- provided a unique set of observations obtained with the ESO Very Large Telescope in Chile and the 10-meter Keck telescope in Hawaii, enabling them to find traces of the material that had surrounded a white dwarf star before it exploded.

New, detailed observations of a supernova show evidence that a white dwarf star "fed" off a red giant to gain the critical mass needed for explosion.

When white dwarf stars explode, they leave behind a rapidly expanding cloud of 'stardust' known as a Type Ia supernova. These exploding events, which shine billions of times brighter than our sun, are all presumed to be extremely similar, and thus have been used extensively as cosmological reference beacons to trace distance and the evolution of the Universe.

Astronomers have now -- for the first time ever -- provided a unique set of observations obtained with the ESO Very Large Telescope in Chile and the 10-meter Keck telescope in Hawaii, enabling them to find traces of the material that had surrounded a white dwarf star before it exploded. Their data set is unique in that no Type Ia supernova event has ever been observed at this level of detail over a several-month period following the explosion.

These observations support a widely accepted model proposing that a white dwarf star interacts with a companion star -- a red giant. Due to the white dwarf's strong gravitational pull, this companion star continuously loses mass through 'force feeding' its gases to the white dwarf. When the mass of the white dwarf grows past a critical value, it explodes.

Through their observations, which took place over the course of four months, and combined with archival data, the astronomers detected the presence of a number of expanding shells surrounding a Type Ia super-nova event. The make-up of these shells suggests they are the remnants of the red giant star that fed the white dwarf.

These results were recently published in the journal Science. The data were collected by two teams of researchers; one at ESO headed by Dr. Ferdinando Patat, and one at the California Institute of Technology, USA, led by Dr. Avishay Gal-Yam. Dr. Gal-Yam has recently joined the Weizmann Institute of Science as a senior scientist in the Condensed Matter Physics Department.


Story Source:

The above story is based on materials provided by Weizmann Institute of Science. Note: Materials may be edited for content and length.


Cite This Page:

Weizmann Institute of Science. "Shrinking Giants, Exploding Dwarves." ScienceDaily. ScienceDaily, 30 August 2007. <www.sciencedaily.com/releases/2007/08/070828084421.htm>.
Weizmann Institute of Science. (2007, August 30). Shrinking Giants, Exploding Dwarves. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2007/08/070828084421.htm
Weizmann Institute of Science. "Shrinking Giants, Exploding Dwarves." ScienceDaily. www.sciencedaily.com/releases/2007/08/070828084421.htm (accessed September 2, 2014).

Share This




More Space & Time News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: NASA Captures Solar Flare

Raw: NASA Captures Solar Flare

AP (Sep. 1, 2014) NASA reported the sun emitted a mid-level solar flare, on August 24th. NASA's Solar Dynamics Observatory captured the images of the flare, which erupted on the left side of the sun. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Space Shuttle Discovery's Legacy, 30 Years Later

Space Shuttle Discovery's Legacy, 30 Years Later

Newsy (Aug. 30, 2014) The space shuttle Discovery launched for the very first time 30 years ago. Here's a look back at its legacy. Video provided by Newsy
Powered by NewsLook.com
Experiment Tests Whether Universe Is Actually A Hologram

Experiment Tests Whether Universe Is Actually A Hologram

Newsy (Aug. 27, 2014) Researchers at Fermilab are using a device called "The Holometer" to test whether our universe is actually a 2-D hologram that just seems 3-D. Video provided by Newsy
Powered by NewsLook.com
SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. 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