Paranormal Psychic Forums

Psychic paranormal community Forums for like minded individuals who wish to connect, chat and share.

Contracting white dwarf observed for the first time

Bringing some of the mysteries of the universe a little closer to home.

User avatar
Owlscrying
Posts: 1811
Joined: Mon Apr 03, 2017 3:21 am

Unread post Wed Nov 15, 2017 4:32 pm

Astrophysicists from MSU (Russia) and colleagues from Italy and Russian Academy of Sciences have found the first observational evidence for a contracting white dwarf. Constant high spin-up rate of a star of this type, located in an enigmatic binary system, can be easily explained if the white dwarf is contracting, the researchers argue. The discovery is reported in the Monthly Notices of the Royal Astronomical Society.

"Thanks to this discovery, astrophysicists will be able to study and evaluate the evolution patterns of young white dwarfs—and successfully look for similar systems in the galaxy," noted the main author of the article, astrophysicist Sergei Popov (SAI MSU).

It is widely believed, based on theoretical considerations, that young white dwarfs should experience a phase of contraction in their early life. The radius of a typical white dwarf can decrease by several hundred kilometers during its first million years. However, there was no observational evidence for this effect up to now, because most of the known white dwarfs are much older, and because scientists do not have a direct way to measure the variations of radii in these stars.

Source

 
Image

User avatar
Owlscrying
Posts: 1811
Joined: Mon Apr 03, 2017 3:21 am

Unread post Wed Nov 15, 2017 4:34 pm

Image
Credit: Francesco Mereghetti

White dwarf from HD49798/RX J0648.0-4418.

Source / Image Courtesy

 
Image

User avatar
Owlscrying
Posts: 1811
Joined: Mon Apr 03, 2017 3:21 am

Unread post Wed Nov 15, 2017 4:35 pm



An exotic binary star system 380 light-years away has been identified as an elusive white dwarf pulsar – the first of its kind ever to be discovered in the universe – thanks to research by the University of Warwick.

Professors Tom Marsh and Boris Gänsicke of the University of Warwick’s Astrophysics Group, with Dr David Buckley from the South African Astronomical Observatory, have identified the star AR Scorpii (AR Sco) as the first white dwarf version of a pulsar – objects found in the 1960s and associated with very different objects called neutron stars.

The white dwarf pulsar has eluded astronomers for over half a century.

AR Sco contains a rapidly spinning, burnt-out stellar remnant called a white dwarf, which lashes its neighbour – a red dwarf – with powerful beams of electrical particles and radiation, causing the entire system to brighten and fade dramatically twice every two minutes.
The latest research establishes that the lash of energy from AR Sco is a focused ‘beam’, emitting concentrated radiation in a single direction – much like a particle accelerator – something which is totally unique in the known universe.

AR Sco lies in the constellation Scorpius, 380 light-years from Earth, a close neighbour in astronomical terms. The white dwarf in AR Sco is the size of Earth but 200,000 times more massive, and is in a 3.6 hour orbit with a cool star one third the mass of the Sun.

With an electromagnetic field 100 million times more powerful than Earth, and spinning on a period just shy of two minutes, AR Sco produces lighthouse-like beams of radiation and particles, which lash across the face of the cool star, a red dwarf.
Image

Post Reply

Return to “The Universe”

  • Information
  • Who is online

    Users browsing this forum: No registered users and 2 guests