Featured Research

from universities, journals, and other organizations

Solving a supernova mystery

Date:
December 14, 2011
Source:
Carnegie Institution
Summary:
A team of scientists has observed the early stages of a Type Ia supernova that is only 21 million light years away from Earth -- the closest of its kind discovered in 25 years. The team's detection of a supernova less than half a day after it exploded will refine and challenge our understanding of these stellar phenomena.

SN 2011fe in the Pinwheel Galaxy (M101) at maximum brightness, a composite of optical data from the Las Cumbres Observatory Global Telescope Network 0.8m Byrne Observatory Telescope at the Sedgwick Reserve and (purple) hydrogen emission data from the Palomar Transient Factory. The left side shows the galaxy with no labels and the right shows the same with the SN2011fe labeled.
Credit: Image courtesy of Carnegie Institution

A team of scientists, including Carnegie's Mansi M. Kasliwal, has observed the early stages of a Type Ia supernova that is only 21 million light years away from Earth--the closest of its kind discovered in 25 years. The Palomar Transient Factory team's detection of a supernova less than half a day after it exploded will refine and challenge our understanding of these stellar phenomena. Their breakthrough observations are published December 15 in Nature.

Related Articles


Type Ia supernovae are violent stellar explosions. Observations of their brightness are used to determine distances in the universe and have shown scientists that the universe is expanding at an accelerating rate. The Nobel Prize in Physics was awarded December 10 to three astronomers for their "discovery of the accelerating expansion of the Universe through observations of distant supernovae."

The PTF team, led by Professor Shri Kulkarni of the California Institute of Technology, discovered this supernova, named SN2011fe, just 11 hours after it exploded. They were able to pinpoint the explosion in the Pinwheel Galaxy to August 23 at about 4:30 p.m. Universal Time.

"For several years, I had been taking images with robotic telescopes at Palomar Observatory of the Pinwheel Galaxy every night I possibly could, hoping it would give birth to a rare cosmic feat," Kasliwal said. "When we saw SN2011fe, I fell off my chair as its brightness was too faint to be a supernova and too bright to be nova. Only follow-up observations in the next few hours revealed that this was actually an exceptionally young Type Ia supernova."

The widely accepted theory is that Type Ia supernovae are thermonuclear explosions of a white dwarf star that's part of a binary system--two stars that are physically close and orbit around a common center of mass.

There are two different models for how Type Ia supernovae are created from this type of binary system. In the so-called double-degenerate (or DD) model, the orbit between two white dwarf stars shrinks until the lighter star's path is disrupted and it moves close enough for some of its matter to be absorbed into the primary white dwarf and initiate an explosion. In the so-called single-degenerate (or SD) model, the white dwarf slowly accretes mass from a different, non-white dwarf type of star, until it reaches an ignition point. There are three potential methods for the transfer of mass and--depending on which one is used--the second star is likely to be a red giant, a helium star, or a so-called subgiant or main-sequence star.

Observations of the early stages of the supernova--presented in a paper by lead author Peter Nugent of Lawrence Berkeley Laboratory--showed direct evidence that the primary star was a type of white dwarf called a carbon-oxygen white dwarf. Very sensitive and early radio and X-ray observations, presented in a separate paper to be published in The Astrophysical Journal, show no evidence of interaction with surrounding material. Combining this data with an analysis of historical images, the team ruled out luminous red giants and the vast majority of helium stars for the second star in the binary system before the explosion.

These clues meant that the secondary star was either another white dwarf, as in the DD model, or a subgiant or main-sequence star, as created by one of the three SD model methods.

Analysis of the matter ejected by the supernova's explosion suggests that the second star is less likely to be another white dwarf. Thus, the solution to the mystery of SN2011fe's origin is probably a primary white dwarf accreting matter from a neighboring subgiant or main-sequence star.

"The fact that we discovered this supernova in its infancy, and that the Pinwheel Galaxy is in our cosmic backyard, has given us an unprecedented opportunity to make this the best studied supernova to date," Kulkarni said.


Story Source:

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


Journal References:

  1. Peter E. Nugent, Mark Sullivan, S. Bradley Cenko, Rollin C. Thomas, Daniel Kasen, D. Andrew Howell, David Bersier, Joshua S. Bloom, S. R. Kulkarni, Michael T. Kandrashoff, Alexei V. Filippenko, Jeffrey M. Silverman, Geoffrey W. Marcy, Andrew W. Howard, Howard T. Isaacson, Kate Maguire, Nao Suzuki, James E. Tarlton, Yen-Chen Pan, Lars Bildsten, Benjamin J. Fulton, Jerod T. Parrent, David Sand, Philipp Podsiadlowski, Federica B. Bianco, Benjamin Dilday, Melissa L. Graham, Joe Lyman, Phil James, Mansi M. Kasliwal, Nicholas M. Law, Robert M. Quimby, Isobel M. Hook, Emma S. Walker, Paolo Mazzali, Elena Pian, Eran O. Ofek, Avishay Gal-Yam, Dovi Poznanski. Supernova SN 2011fe from an exploding carbon–oxygen white dwarf star. Nature, 2011; 480 (7377): 344 DOI: 10.1038/nature10644
  2. Weidong Li, Joshua S. Bloom, Philipp Podsiadlowski, Adam A. Miller, S. Bradley Cenko, Saurabh W. Jha, Mark Sullivan, D. Andrew Howell, Peter E. Nugent, Nathaniel R. Butler, Eran O. Ofek, Mansi M. Kasliwal, Joseph W. Richards, Alan Stockton, Hsin-Yi Shih, Lars Bildsten, Michael M. Shara, Joanne Bibby, Alexei V. Filippenko, Mohan Ganeshalingam, Jeffrey M. Silverman, S. R. Kulkarni, Nicholas M. Law, Dovi Poznanski, Robert M. Quimby, Curtis McCully, Brandon Patel, Kate Maguire, Ken J. Shen. Exclusion of a luminous red giant as a companion star to the progenitor of supernova SN 2011fe. Nature, 2011; 480 (7377): 348 DOI: 10.1038/nature10646

Cite This Page:

Carnegie Institution. "Solving a supernova mystery." ScienceDaily. ScienceDaily, 14 December 2011. <www.sciencedaily.com/releases/2011/12/111214135741.htm>.
Carnegie Institution. (2011, December 14). Solving a supernova mystery. ScienceDaily. Retrieved January 30, 2015 from www.sciencedaily.com/releases/2011/12/111214135741.htm
Carnegie Institution. "Solving a supernova mystery." ScienceDaily. www.sciencedaily.com/releases/2011/12/111214135741.htm (accessed January 30, 2015).

Share This


More From ScienceDaily



More Space & Time News

Friday, January 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Video Shows Stars If They Were as Close to Earth as Sun

Video Shows Stars If They Were as Close to Earth as Sun

Buzz60 (Jan. 30, 2015) Russia&apos;s space agency created a video that shows what our sky would look like with different star if they were as close as our sun. Patrick Jones (@Patrick_E_Jones) walks us through the cool video. Video provided by Buzz60
Powered by NewsLook.com
Dog-Loving Astronaut Wins Best Photo of 2015

Dog-Loving Astronaut Wins Best Photo of 2015

Buzz60 (Jan. 30, 2015) Retired astronaut and television host, Leland Melvin, snuck his dogs into the NASA studio so they could be in his official photo. As Mara Montalbano (@maramontalbano) shows us, the secret is out. Video provided by Buzz60
Powered by NewsLook.com
NASA Holds Memorial to Remember Astronauts

NASA Holds Memorial to Remember Astronauts

AP (Jan. 29, 2015) NASA is remembering 17 astronauts who were killed in the line of duty and dozens more who have died since the agency&apos;s beginning. A remembrance ceremony was held Thursday at NASA&apos;s Marshall Space Flight Center in Alabama. (Jan. 29) Video provided by AP
Powered by NewsLook.com
Asteroid's Moon Spotted During Earth Flyby

Asteroid's Moon Spotted During Earth Flyby

Rumble (Jan. 27, 2015) Scientists working with NASA&apos;s Deep Space Network antenna at Goldstone, California discovered an unexpected moon while observing asteroid 2004 BL86 during its recent flyby past Earth. Credit to &apos;NASA JPL&apos;. Video provided by Rumble
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:

More Coverage


Supernova Caught in the Act

Dec. 14, 2011 The earliest detection ever of a Type Ia supernova has led to unparalleled observations of the initial stages of the supernova and characterization of the stars that formed it. Early detection and ... read more

'Supernova of a Generation' Shows Its Stuff: Astronomers Determine How Brightest and Closest Stellar Explosion in 25 Years Happened

Dec. 14, 2011 It was the brightest and closest stellar explosion seen from Earth in 25 years, dazzling professional and backyard astronomers alike. Now, thanks to this rare discovery -- which some have called the ... read more

New Findings About the 'supernova of a Generation'

Dec. 14, 2011 Astrophysicists have discovered that a supernova that exploded in August -- dubbed the supernova of a generation -- was a "white dwarf" star, and that its companion star could not have been ... read more

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