White dwarf and ultra-cool dwarf keep their distance

Apr 18, 2007

Scientists from the University of Hertfordshire have discovered a rare binary system consisting of a white dwarf, a Sun-like star that has reached the end of its life, and an ultra-cool dwarf, which is the smallest kind of star. To make the discovery even more unusual, the co-orbiting pair has by far the widest separation ever detected in this type of binary system.

Avril Day-Jones, who is presenting results at the RAS National Astronomy Meeting in Preston, said, “This is a record breaking discovery for a system of this kind. In the other few binary cases that are known, the objects are relatively close together. In this new system, the objects are 600 billion kilometres apart which is hundreds of times wider.”

The group from Hertfordshire believes that the two objects formed at roughly the same time and were originally much closer together. During the death-throes of the white dwarf’s progenitor star, forces induced when gas and dust from the star were thrown off into space caused the ultra-cool dwarf spiral out to its remote position.

Miss Day-Jones said, “Ultra-cool dwarfs are elusive objects and we don’t know that much about them. This type of binary allows us to use our knowledge of white dwarfs, which we understand quite well, to infer properties of the ultra-cool dwarf, such as the temperature, surface gravity, mass and age. We need to discover more of this type of binary system if we want to improve our understanding of ultra-cool dwarfs.”

Source: RAS

Explore further: Astronomers solve decades-long mystery of the 'lonely old stars'

Related Stories

DARPA seeks new positioning, navigation, timing solutions

2 hours ago

The Defense Advanced Research Projects Agency (DARPA), writing about GPS, said: "The military relies heavily on the Global Positioning System (GPS) for positioning, navigation, and timing (PNT), but GPS access is easily blocked by methods such as jamming. In addition, many environments in which our mil ...

Lights out in Australia as Earth Hour kicks off

2 hours ago

The Sydney Harbour Bridge and the sails on the nearby Opera House went dark Saturday, as lights on landmarks around Australia were switched off for the global climate change awareness campaign Earth Hour.

Future US Navy: Robotic sub-hunters, deepsea pods

6 hours ago

The robotic revolution that transformed warfare in the skies will soon extend to the deep sea, with underwater spy "satellites," drone-launching pods on the ocean floor and unmanned ships hunting submarines.

Recommended for you

Dusty substructure in a galaxy far far away

18 hours ago

Scientists at the Max Planck Institute for Astrophysics (MPA) have combined high-resolution images from the ALMA telescopes with a new scheme for undoing the distorting effects of a powerful gravitational ...

ALMA disentangles complex birth of giant stars

18 hours ago

A research group led by Aya Higuchi, a researcher at Ibaraki University, conducted observations of the massive-star forming region IRAS 16547-4247 with the Atacama Large Millimeter/submillimeter Array (ALMA). ...

Image: The tumultuous heart of the Large Magellanic Cloud

Mar 31, 2015

A scene of jagged fiery peaks, turbulent magma-like clouds and fiercely hot bursts of bright light. Although this may be reminiscent of a raging fire or the heart of a volcano, it actually shows a cold cosmic ...

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.