Stability lost as supernovae explode

May 15, 2014
Supernova
Credit: NASA

Exploding supernovae are a phenomenon that is still not fully understood. The trouble is that the state of nuclear matter in stars cannot be reproduced on Earth.

In a recent paper published in European Physical Journal E, Yves Pomeau from the University of Arizona, USA, and his French colleagues from the CNRS provide a new model of supernovae represented as dynamical systems subject to a loss of stability, just before they explode. Because similar stability losses also occur in in nature, this model could be used to predict before they happen. Previous studies of the creeping of soft solids, earthquakes, and sleep-wake transitions have already confirmed the validity of this approach.

The authors show that the stars' loss of stability can be described in mathematical terms as a so-called dynamical saddle-node bifurcation. This approach makes it possible to devise a universal equation describing supernovae dynamics at its onset, taking into account the initial physical conditions of stability. Unlike previous studies, this one sheds light on why the time scale of a —lasting between ten and thirty seconds—is considerably shorter than the overall pace of evolution of the star, in the billion year range.

This study also attempts to elucidate whether supernova explosions are genuine and do not result from a reversed implosion. Indeed, are believed to be initially subjected to an inward flow—as the star's core may collapse into a neutron star or a black hole—that is subsequently superseded by the violent outward flow of the supernova explosion. The authors attempt to explain this phenomenon through a detailed model, demonstrating that the star enters a global free fall following its loss of stability.

Explore further: ISOLDE sheds light on dying stars

More information: Y. Pomeau, M. Le Berre, P.H. Chavanis, and B. Denet (2013), Supernovae: an example of complexity in the physics of compressible fluids, European Physical Journal E, DOI: 10.1140/epje/i2014-14026-1

add to favorites email to friend print save as pdf

Related Stories

ISOLDE sheds light on dying stars

Apr 04, 2014

What happens inside a dying star? A recent experiment at CERN's REX accelerator offers clues that could help astrophysicists to recalculate the ages of some of the largest explosions in the universe.

Hubble catches stellar explosions in NGC 6984

Nov 08, 2013

Supernovae are intensely bright objects. They are formed when a star reaches the end of its life with a dramatic explosion, expelling most of its material out into space.

NuSTAR telescope takes first peek into core of supernova

Feb 19, 2014

(Phys.org) —Astronomers have peered for the first time into the heart of an exploding star in the final minutes of its existence. The feat by the high-energy X-ray satellite NuSTAR provides details of the ...

Astronomers discover new kind of supernova

Mar 26, 2013

(Phys.org) —Supernovae were always thought to occur in two main varieties. But a team of astronomers including Carnegie's Wendy Freedman, Mark Phillips and Eric Persson is reporting the discovery of a new ...

Recommended for you

Image: Multicoloured view of supernova remnant

7 hours ago

Most celestial events unfold over thousands of years or more, making it impossible to follow their evolution on human timescales. Supernovas are notable exceptions, the powerful stellar explosions that make ...

Ultra-luminous X-ray sources in starburst galaxies

7 hours ago

Ultra-luminous X-ray sources (ULXs) are point sources in the sky that are so bright in X-rays that each emits more radiation than a million suns emit at all wavelengths. ULXs are rare. Most galaxies (including ...

When a bright light fades

7 hours ago

Astronomer Charles Telesco is primarily interested in the creation of planets and stars. So, when the University of Florida's giant telescope was pointed at a star undergoing a magnificent and explosive death, ...

Image: Horsehead nebula viewed in infrared

7 hours ago

Sometimes a horse of a different color hardly seems to be a horse at all, as, for example, in this newly released image from NASA's Spitzer Space Telescope. The famous Horsehead nebula makes a ghostly appearance ...

The Milky Way's new neighbour

8 hours ago

The Milky Way, the galaxy we live in, is part of a cluster of more than 50 galaxies that make up the 'Local Group', a collection that includes the famous Andromeda galaxy and many other far smaller objects. ...

Image: Hubble sweeps a messy star factory

8 hours ago

This sprinkle of cosmic glitter is a blue compact dwarf galaxy known as Markarian 209. Galaxies of this type are blue-hued, compact in size, gas-rich, and low in heavy elements. They are often used by astronomers ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.