Featured Research

from universities, journals, and other organizations

Astronomers identify 12-billion-year-old white dwarf stars only 100 light years away

Date:
April 11, 2012
Source:
University of Oklahoma
Summary:
Astronomers have identified two white dwarf stars considered the oldest and closest known. Astronomers identified these 11- to 12-billion-year-old white dwarf stars only 100 light years away from Earth. These stars are the closest known examples of the oldest stars in the universe forming soon after the Big Bang.

Astronomers identified 11- to 12-billion-year-old white dwarf stars only 100 light years away from Earth. These stars are the closest known examples of the oldest stars in the Universe forming soon after the Big Bang, according to the researchers.
Credit: Image courtesy of University of Oklahoma

A University of Oklahoma assistant professor and colleagues have identified two white dwarf stars considered the oldest and closest known. Astronomers identified these 11- to 12-billion-year-old white dwarf stars only 100 light years away from Earth. These stars are the closest known examples of the oldest stars in the Universe forming soon after the Big Bang, according to the OU research group.

Related Articles


Mukremin Kilic, assistant professor of physics and astronomy in the OU College of Arts and Sciences and lead author on a recently published paper, announced the discovery. Kilic says, "A white dwarf is like a hot stove; once the stove is off, it cools slowly over time. By measuring how cool the stove is, we can tell how long it has been off. The two stars we identified have been cooling for billions of years."

Kilic explains that white dwarf stars are the burned out cores of stars similar to the Sun. In about 5 billion years, the Sun also will burn out and turn into a white dwarf star. It will lose its outer layers as it dies and turn into an incredibly dense star the size of Earth.

Known as WD 0346+246 and SDSS J110217, 48+411315.4 (J1102), these stars are located in the constellations Taurus and Ursa Major, respectively. Kilic and colleagues obtained infrared images using NASA's Spitzer Space Telescope to measure the temperature of the stars. And, over a three-year period, they measured J1102's distance by tracking its motion using the MDM Observatory's 2.4m telescope near Tucson, Arizona.

"Most stars stay almost perfectly fixed in the sky, but J1102 is moving at a speed of 600,000 miles per hour and is a little more than 100 light years from Earth," remarks co-author John Thorstensen of Dartmouth College. "We found its distance by measuring a tiny wiggle in its path caused by the Earth's motion -- it's the size of a dime viewed from 80 miles away."

"Based on the optical and infrared observations of these stars and our analysis, these stars are about 3700 and 3800 degrees on the surface," said co-author Piotr Kowalski of Helmholtz Centre Potsdam in Germany. Kowalski modeled the atmospheric parameters of these stars. Based on these temperature measurements, Kilic and his colleagues were able to estimate the ages of the stars.

"It is like a crime scene investigation," added Kilic. "We measure the temperature of the dead body -- in our case a dead star, then determine the time of the crime. These two white dwarf stars have been dead and cooling off almost for the entire history of the Universe."

Kilic was the lead author on the paper accepted for publication in the Monthly Notices of the Royal Astronomical Society. Kilic's co-authors include John Thorstensen, Dartmouth College; Piotr Kowalski, Helmholtz Centre Potsdam, Germany; and Jeff Andrews, Columbia University.


Story Source:

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


Cite This Page:

University of Oklahoma. "Astronomers identify 12-billion-year-old white dwarf stars only 100 light years away." ScienceDaily. ScienceDaily, 11 April 2012. <www.sciencedaily.com/releases/2012/04/120411144326.htm>.
University of Oklahoma. (2012, April 11). Astronomers identify 12-billion-year-old white dwarf stars only 100 light years away. ScienceDaily. Retrieved March 30, 2015 from www.sciencedaily.com/releases/2012/04/120411144326.htm
University of Oklahoma. "Astronomers identify 12-billion-year-old white dwarf stars only 100 light years away." ScienceDaily. www.sciencedaily.com/releases/2012/04/120411144326.htm (accessed March 30, 2015).

Share This


More From ScienceDaily



More Space & Time News

Monday, March 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

What NASA Wants To Learn From Its 'Year In Space' Tests

What NASA Wants To Learn From Its 'Year In Space' Tests

Newsy (Mar. 28, 2015) Astronaut Scott Kelly and cosmonaut Mikhail Kornienko will spend a year in space running tests on human physiology and psychology. Video provided by Newsy
Powered by NewsLook.com
Crew Starts One-Year Space Mission

Crew Starts One-Year Space Mission

Reuters - News Video Online (Mar. 28, 2015) Russian-U.S. crew arrives safely at the International Space Station for the start of a ground-breaking year-long stay. Paul Chapman reports. Video provided by Reuters
Powered by NewsLook.com
Why So Many People Think NASA's Asteroid Mission Is A Waste

Why So Many People Think NASA's Asteroid Mission Is A Waste

Newsy (Mar. 27, 2015) The Asteroid Retrieval Mission announced this week bears little resemblance to its grand beginnings. Even NASA scientists are asking, "Why bother?" Video provided by Newsy
Powered by NewsLook.com
Space Station Crew Docks Safely

Space Station Crew Docks Safely

Reuters - News Video Online (Mar. 27, 2015) NASA TV footage shows the successful docking of a Russian Soyuz craft to the International Space Station for a year-long mission. Rough cut (no reporter narration). Video provided by Reuters
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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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