Solar Energy News  
STELLAR CHEMISTRY
Surface helium detonation spells end for white dwarf
by Staff Writers
Tokyo, Japan (SPX) Oct 05, 2017


The nuclear detonation of the surface helium layer triggered an inward shock wave, and now carbon nuclear fusion has begun at the center.

Some stars end their lives with a huge explosion called a supernova. The most famous supernovae are the result of a massive star exploding, but a white dwarf, the remnant of an intermediate mass star like our Sun, can also explode.

This can occur if the white dwarf is part of a binary star system. The white dwarf accretes material from the companion star, then at some point, it might explode as a type Ia supernova.

Because of the uniform and extremely high brightness (about 5 billion times brighter than the Sun) of type Ia supernovae, they are often used for distance measurements in astronomy. However, astronomers are still puzzled by how these explosions are ignited. Moreover, these explosions only occur about once every 100 years in any given galaxy, making them difficult to catch.

An international team of researchers led by Ji-an Jiang, a graduate student of the University of Tokyo, and including researchers from the University of Tokyo, the Kavli Institute for the Physics and Mathematics of the Universe (IPMU), Kyoto University, and the National Astronomical Observatory of Japan (NAOJ), tried to solve this problem.

To maximize the chances of finding a type Ia supernova in the very early stages, the team used Hyper Suprime-Cam mounted on the Subaru Telescope, a combination which can capture an ultra-wide area of the sky at once. Also they developed a system to detect supernovae automatically in the heavy flood of data during the survey, which enabled real-time discoveries and timely follow-up observations.

They discovered over 100 supernova candidates in one night with Subaru/Hyper Suprime-Cam, including several supernovae that had only exploded a few days earlier. In particular, they captured a peculiar type Ia supernova within a day of it exploding. Its brightness and color variation over time are different from any previously-discovered type Ia supernova.

They hypothesized this object could be the result of a white dwarf with a helium layer on its surface. Igniting the helium layer would lead to a violent chain reaction and cause the entire star to explode.

This peculiar behavior can be totally explained with numerical simulations calculated using the supercomputer ATERUI. "This is the first evidence that robustly supports a theoretically predicted stellar explosion mechanism!" said Jiang.

This result is a step towards understand the beginning of type Ia supernovae. The team will continue to test their theory against other supernovae, by detecting more and more supernovae just after the explosion. The details of their study were published in Nature on October 5.

STELLAR CHEMISTRY
Violent helium reaction on white dwarf surface triggers supernova explosion
San Francisco CA (SPX) Oct 09, 2017
An international team of researchers has found evidence a supernova explosion that was first triggered by a helium detonation, reports a new study in Nature this week. A Type Ia supernova is a type of white dwarf star explosion that occurs in a binary star system where two stars are circling one another. Because these supernovae shine 5 billion times brighter than the Sun they are used in ... read more

Related Links
National Institutes of Natural Sciences
Stellar Chemistry, The Universe And All Within It


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

STELLAR CHEMISTRY
A key step in synthetic fuel production from seawater patented by NRL

Breakthrough in direct activation of CO2 and CH4 into liquid fuels and chemicals

Surrounded by potential: New science in converting biomass

Olive mill wastewater transformed: From pollutant to bio-fertilizer, biofuel

STELLAR CHEMISTRY
US spacewalkers repair aging ISS robotic arm

Servosila introduces Mobile Robots equipped with Software Defined Radio payloads

Mattel scraps plan for digital assistant for kids

Sensitivity to time improves performance at remotely controlling devices

STELLAR CHEMISTRY
Germany gets economic lift with wind energy

French energy company to build wind power sector in India

Finding better wind energy potential with the new European Wind Atlas

Last of the 67 turbines for a British wind farm installed

STELLAR CHEMISTRY
The U.S. needs at least twice as many charging points for EV

Uber competitor hits Paris roads with Chinese help

UK car sales skid lower in September on poor consumer confidence

Renault plans China growth, more electric vehicles

STELLAR CHEMISTRY
A new way to produce clean hydrogen fuel from water using sunlight

Ultra-fast and ultra-sensitive hydrogen sensor

Tesla delays truck launch, eyes battery power for Puerto Rico

New nanomaterial can extract hydrogen fuel from seawater

STELLAR CHEMISTRY
New 'molecular trap' cleans more radioactive waste from nuclear fuel rods

Largest Nuclear Training Center In France Opens Its Doors

BWXT awarded contract extension for nuclear waste facility operations

UAE to open Arab Gulf's first nuclear reactor in 2018

STELLAR CHEMISTRY
'Fuel-secure' steps in Washington counterintuitive, green group says

SLAC-led project will use AI to prevent or minimize electric grid failures

Scientists propose method to improve microgrid stability and reliability

ADB: New finance model needed for low-carbon shift in Asia

STELLAR CHEMISTRY
Predicting insect feeding preferences after deforestation

DNA barcoding technology helping monitor health of all-important boreal forest

Poland rejects EU evidence on primeval forest dispute

Forest loss means tropics emit more carbon than they trap: study









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.