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    Surface Helium Detonation Spells End for White Dwarf

    October 5, 2017, Categories  Uncategorized

    A hybrid type Ia supernova with an early flash triggered by helium-shell detonation. Nature, 2017; 550 (7674): 80 DOI: 10.1038/nature23908

    A hybrid type Ia supernova with an early flash triggered by helium-shell detonation. Nature, 2017; 550 (7674): 80 DOI: 10.1038/nature23908

    Researchers have found evidence that the brightest stellar explosions in our Universe could be triggered by helium nuclear detonation near the surface of a white dwarf star. 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 ...

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    Very Rare Discovery: Failed Star Orbits a Dead Star every 71 minutes

    June 11, 2017, Categories  Astronomy/Space

    K2 lightcurve (black jagged curve) folded about a period of 71.23 minutes. The red curve represents a simple geometrical model with a 5-minute long total eclipse and a 9% contribution to emulate an illumination effect on the companion star. The blue curve is the fit to the model based on the length of the K2 observations. Credit: Bishop's University

    1. K2 lightcurve (black jagged curve) folded about a period of 71.23 minutes. The red curve represents a simple geometrical model with a 5-minute long total eclipse and a 9% contribution to emulate an illumination effect on the companion star. The blue curve is the fit to the model based on the length of the K2 observations. 2. The final fate of WD1202 as a cataclysmic variable. The brown dwarf overflows its tear-drop-shaped Roche lobe and loses mass to the compact white dwarf accretor An accretion disk of hot hydrogen gas surrounds the white dwarf. Credit: Bishop’s University

    An international team using data from the rejuvenated Kepler space telescope have discovered a rare gem: A binary system consisting of a failed star, also known as a brown dwarf, and the remnant of a dead star known ...

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    Calculations Show Close Ia Supernova should be Neutrino detectable offering possibility of identifying Explosion type

    March 5, 2017, Categories  Astronomy/Space

    Density contour plots including deflagration (white) and detonation (green) surfaces. Credit: arXiv:1609.07403 [astro-ph.HE] Read more at: https://phys.org/news/2017-03-ia-supernova-neutrino-possibility-explosion.html#jCp

    Density contour plots including deflagration (white) and detonation (green) surfaces. Credit: arXiv:1609.07403 [astro-ph.HE]

    A team of researchers at North Carolina State University has found that current and future neutrino detectors placed around the world should be capable of detecting neutrinos emitted from a relatively close supernova. They also suggest that measuring such neutrinos would allow them to explain what goes on inside of a star during such an explosion—if the measurements match one of two models the team built to describe the inner workings of a supernova.

    Supernovae have been classified into different types depending on what causes them to occur—one type, a la supernova, occurs when a white dwarf pulls in enough material from a companion, eventually triggering carbon fus...

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    Will Earth still exist 5 Billion years from now?

    December 9, 2016, Categories  Astronomy/Space

    This is a schematic view of the candidate planet's orbit in L2 Puppis disk. Credit: © P. Kervella (CNRS / U. de Chile / Observatoire de Paris / LESIA)

    This is a schematic view of the candidate planet’s orbit in L2 Puppis disk. Credit: © P. Kervella (CNRS / U. de Chile / Observatoire de Paris / LESIA)

    Old Star offers sneak preview of the future. What will happen to Earth when, in a few billion years’ time, the Sun is a hundred times bigger than it is today? Using the most powerful radio telescope in the world, an international team of astronomers has set out to look for answers in the star L2 Puppis. 5 billion years ago, this star was very similar to the Sun as it is today.

    “Five billion years from now, the Sun will have grown into a red giant star, more than a hundred times larger than its current size,” says Professor Leen Decin from the KU Leuven Institute of Astronomy...

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