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#Star collision may explain the lonely supernova University of Warwick rightoriginal Studyposted by Tom Frew-Warwick on August 11 2014 A massive collision between white dwarf
instead between a white dwarf star and neutron star it would fit their observations because: hat we therefore propose is these are systems that have been ejected from their galaxy.
A good candidate in this scenario is a white dwarf and a neutron star in a binary system. The neutron star is formed
and if the binary system survives the kick the white dwarf and neutron star will merge causing the explosive transient. he researchers who say such merging systems of white dwarfs
and neutron stars may produce high energy gamma-ray bursts will next look for any new examples of calcium-rich transients to confirm this.
which monitors two thousand red dwarf stars for transiting planets. The planet was targeted next for follow-up observations to characterize its atmosphere.
our solar system orbiting a white dwarf star 170 light years away. Using observations obtained with the Hubble Space Telescopeâ
In the study published in Science researchers suggest it is most likely that the water detected around the white dwarf GD 61 came from a minor planet at least 90 kilometers (56 miles) in diameterâ
##but potentially much biggerâ##that once orbited the parent star before it became a white dwarf.
From the amount of rocks and water detected in the outer envelope of the white dwarf the researchers estimate that the disrupted planetary body had a diameter of at least 90 kilometers.
and became a white dwarf yet parts of its planetary system survived. The water-rich minor planet was knocked out of its regular orbit
Researchers believe that destabilizing the orbit of the minor planet requires a so far unseen much larger planet going around the white dwarf. t this stage in its existence all that remains of this rocky body is simply dust
. or their analysis the researchers used ultraviolet spectroscopy data obtained with the Cosmic Origins Spectrograph on board the Hubble space telescope of the white dwarf GD 61.
The Hubble and Keck data allows the researchers to identify the different chemical elements that are polluting the outer layers white dwarf.
Using a sophisticated computer model of the white dwarf atmosphere developed by Detlev Koester at the University of Kiel they were able to infer the chemical composition of the shredded minor planet.
which a white dwarf star somehow reaches a critical mass of about 1. 4 solar masses and explodes.
They found the classic signature of a thermonuclear explosion of a white dwarf. The process begins with the compression of the white dwarf leading to the formation of nickel-56
which decays to cobalt-56 which in turn decays to a stable isotope of iron producing characteristic gamma rays.
In the favoured model called the single degenerate system a white dwarf reaches its critical mass by stealing material from an ordinary companion star.
In an alternative double degenerate model two white dwarfs orbiting each other cause the explosion either by merging or by one poaching matter from the other.
In a single degenerate system the shock wave from the white dwarf explosion should smash into the surrounding gas from the companion star generating radio waves.
so concluded SN 2014j probably began as two white dwarfs. Robert Kirshner of Harvard university who studies type IA supernovae is convinced not yet.
and his team used a technique called gravitational microlensing to study a binary system with two red dwarfs small stars that are dimmer than the sun. The distance between the stars is about 10 to 15 times that of Earth
But this discovery argues that yes indeed at least in this system of two red dwarfs you can form planets at these sorts of longer distances says Gaudi.
Sometimes when a white dwarf star dies it explodes as a type 1a supernova. All supernovae in this class reach a very specific colour and peak brightness creating
and thought to be caused by the collision of two neutron stars black holes or white dwarfs. The pair suggest that the odd isotope levels in the trees
while looking for brown dwarfs or â##failed stars. â#PSO J318. 5-22â#s ultrared color stood apart from the other objects in the survey astronomers said.
The#study detailed the prevalence of these planets orbiting red dwarf stars and found#that about 15 percent have Earth-size planets within habitable zones.
#Red dwarfs#are one-third the size and one-thousandth as bright as the sun. But in this week's PNAS Online Early Edition a team of researchers from#University of California at#Berkeley released a study that looks at how common Earth-size planets
These stars'surface temperatures range from just a bit hotter than the sun's 5778 Kelvin to as cool as 4100 Kelvin all of which are hotter than the M-class red dwarfs studied previously.
but from a low-mass star at the boundary between stars and brown dwarfs. The discovery reveals a major difference between the magnetic activity of more-massive stars and that of brown dwarfs and planets,
the scientists said. ll the magnetic activity we see on this object can be explained by powerful auroras,
his indicates that auroral activity replaces solar-like coronal activity on brown dwarfs and smaller objects,
Brown dwarfs, sometimes called ailed stars, are objects more massive than planets, yet too small to trigger the thermonuclear reactions at their cores that power stars.
and brown dwarfs have outer atmospheres that support auroral activity, rather than the type of magnetic activity seen on more-massive and hotter stars.
#First Direct evidence of the Formation Process of Brown dwarfs Using the Very Large Array, an international team of astronomers has discovered jets of material ejected by still-forming young brown dwarfs,
revealing the first direct evidence that brown dwarfs are produced by a scaled-down version of the same process that produces stars.
The astronomers studied a sample of still-forming brown dwarfs in a star-forming region some 450 light-years from Earth in the constellation Taurus,
and found that four of them have the type of jets emitted by more-massive stars during their formation.
The scientists also observed the brown dwarfs with the Spitzer and Herschel space telescopes to confirm their status as very young objects. his is the first time that such jets have been found coming from brown dwarfs at such an early stage of their formation,
and shows that they form in a way similar to that of stars, said Oscar Morata, of the Institute of Astronomy and Astrophysics of the Academia Sinica in Taiwan. hese are the lowest-mass objects that seem to form the same way as stars,
Brown dwarfs are less massive than stars, but more massive than giant planets such as Jupiter. They have insufficient mass to produce the temperatures
whether brown dwarfs form like stars or like planets. Stars form when a giant cloud of gas
Previous evidence strongly suggested that brown dwarfs shared the same formation mechanism as their larger siblings
Based on this discovery, e conclude that the formation of brown dwarfs is scaled a-down version of the process that forms larger stars,
and even look for rocky planets in the habitable zones around nearby M dwarf stars. And because Law and co intend to store all the data produced by the Evryscope,
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