Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Closest, brightest supernova in decades is also a little weird


Faster brightening than expected may typify cosmic yardstick Type Ia supernovae

A bright supernova discovered only six weeks ago in a nearby galaxy is provoking new questions about the exploding stars that scientists use as their main yardstick for measuring the universe.

This image features a color composite of SN 2014J in the 'cigar galaxy' M82, 11.4 million light years away, made from KAIT images obtained through several different filters. The supernova is marked with an arrow. Other round objects are relatively nearby stars in our own Milky Way Galaxy.

Credit: W. Zheng and A. Filippenko, University of California Berkeley

Called SN 2014J, the glowing supernova was discovered by a professor and his students in the United Kingdom on Jan. 21, about a week after the stellar explosion first became visible as a pinprick of light in its galaxy, M82, 11.4 million light years away. Still visible today through small telescopes in the Big Dipper, it is the brightest supernova seen from Earth since SN1987A, 27 years ago, and may be the closest Type Ia supernova – the kind used to measure cosmic distances – in more than 77 years.

When University of California, Berkeley, astronomer Alex Filippenko's research team looked for the supernova in data collected by the Katzman Automatic Imaging Telescope (KAIT) at Lick Observatory near San Jose, Calif., they discovered that the robotic telescope had actually taken a photo of it 37 hours after it appeared, unnoticed, on Jan. 14.

Combining this observation with another chance observation by a Japanese amateur astronomer, Filippenko's team was able to calculate that SN 2014J had unusual characteristics – it brightened faster than expected for a Type Ia supernova and, even more intriguing, it exhibited the same unexpected, rapid brightening as another supernova that KAIT discovered and imaged last year – SN 2013dy.

"Now, two of the three most recent and best-observed Type Ia supernovae are weird, giving us new clues to how stars explode," said Filippenko, referring to a third, though apparently 'normal,' Type Ia supernova, SN 2011fe, discovered three years ago. "This may be teaching us something general about Type Ia supernovae that theorists need to understand. Maybe what we think of as 'normal' behavior for these supernovae is actually unusual, and this weird behavior is the new normal."

A paper describing the SN 2014J observations – the first published on this newly discovered supernova – was posted online this week by The Astrophysical Journal Letters and will appear in the March 1 print issue.

Type Ia supernovae as standard candles

Astronomers noticed decades ago that Type Ia supernovae explode with about the same brightness, no matter where they are in the universe. This makes them good "standard candles" with which to judge distance. In the 1990s, two teams (both of them included Filippenko) used Type Ia supernovae to determine the distances to galaxies, compared distance with velocity and discovered that the universe is expanding faster and faster, rather than slowing down as expected. The teams' leaders, including UC Berkeley astrophysicist Saul Perlmutter, shared the 2011 Nobel Prize in Physics for this discovery.

While the latest discoveries do not contradict these results, refinements in understanding Type Ia explosions could help improve distance measurements and lead to more precise calculations of the expansion rate of the universe, thereby setting constraints on the nature of "dark energy," a still mysterious energy comprising 70 percent of the universe and thought to be responsible for its acceleration.

The new data also provide information about the physics occurring in the core of the explosion.

A Type Ia supernova is thought to be the explosion of a white dwarf – an old and very dense star that has shrunk from the size of the Sun to the size of Earth. When a white dwarf has a stellar companion, it can sometimes gain matter from it until the white dwarf becomes unstable, completely obliterating itself through a gigantic nuclear explosion.

New telescopes to catch more supernovae

Because of the importance of supernovae in measuring the universe, many new telescopes, such as the Palomar Transient Factor in San Diego County and the Pan-STARRS in Hawaii, continually rescan the sky to discover more of them. The KAIT telescope has a smaller field of view than newer ones do, so Filippenko's team has switched its focus to discovering supernovae earlier: it scans the same patches of sky every night or every other night. The sooner a new explosion is discovered, the sooner astronomers can capture information, such as spectra showing how the supernova brightens in different colors or wavelengths.

Last year, for example, KAIT and Filippenko's Lick Observatory Supernova Search (LOSS) team discovered and photographed SN 2013dy within two and a half hours of its appearance, earlier than for any other Type Ia. KAIT, which is operated by postdoctoral scholar WeiKang Zheng, is programmed to automatically take images of likely supernovae in five different wavelength bands, and in 2012 captured one supernova, SN 2012cg, three minutes after its discovery.

"Very, very early observations give us the most stringent constraints on what the star's behavior really is in the first stages of the explosion, rather than just relying on theoretical speculation or extrapolating back from observations at later times, which is like observing adolescents to understand early childhood," Filippenko said.

Filippenko's colleagues include Zheng; UC Berkeley graduate student Isaac Shivvers; assistant specialist Kelsey I. Clubb; postdoctoral scholars Ori D. Fox, Melissa L. Graham, Patrick L. Kelly and Jon C. Mauerhan; and amateur astronomer Koichi Itagaki of the Itagaki Astronomical Observatory in Yamagata, Japan, who captured an image of SN 2014J just 20 hours after it exploded.

The research was funded by the TABASGO Foundation, the Sylvia & Jim Katzman Foundation, the Christopher R. Redlich Fund, Gary and Cynthia Bengier, the Richard and Rhoda Goldman Fund, Weldon and Ruth Wood, and the National Science Foundation.

Robert Sanders | EurekAlert!

More articles from Physics and Astronomy:

nachricht Move over, lasers: Scientists can now create holograms from neutrons, too
21.10.2016 | National Institute of Standards and Technology (NIST)

nachricht Finding the lightest superdeformed triaxial atomic nucleus
20.10.2016 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>