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    Hungry, Hungry White Dwarfs: Solving the Puzzle of Stellar Metal Pollution

    May 5, 2024, Categories  Astronomy/Space

    Planetesimal orbits around a white dwarf. Initially, every planetesimal has a circular, prograde orbit. The kick forms an eccentric debris disk which with prograde (blue) and retrograde orbits (orange).
    Planetesimal orbits around a white dwarf. Initially, every planetesimal has a circular, prograde orbit. The kick forms an eccentric debris disk which with prograde (blue) and retrograde orbits (orange).
    Image Credit
    Steven Burrows/Madigan group

    Dead stars known as white dwarfs, have a mass like the sun while being similar in size to Earth. They are common in our galaxy, as 97% of stars are white dwarfs. As stars reach the end of their lives, their cores collapse into the dense ball of a white dwarf, making our galaxy seem like an ethereal graveyard.

    Despite their prevalence, the chemical makeup of these stellar remnants has been a conundrum for astronomers for years...

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    Metal Scar found on Cannibal Star

    February 28, 2024, Categories  Uncategorized

    A bright white-blue sphere, a star, sits in the upper left of this image on a deep blue background. The top of the star is shaded darker, and it is accompanied by white-blue spherical curved lines that close on the star at its top and bottom. In front of this, in the bottom and right of the image, are many almost black rocky chunks. Parts of them are lighter, lit up where they are facing the star.
    When a star like our Sun reaches the end of its life, it can ingest the surrounding planets and asteroids that were born with it. Now, using the European Southern Observatory’s Very Large Telescope (ESO’s VLT) in Chile, researchers have found a unique signature of this process for the first time — a scar imprinted on the surface of a white dwarf star. The results are published today in The Astrophysical Journal Letters.

    When a star like our Sun reaches the end of its life, it can ingest the surrounding planets and asteroids that were born with it. Now, using the European Southern Observatory’s Very Large Telescope (ESO’s VLT) in Chile, researchers have found a unique signature of this process for the first time — a scar imprinted on the surface of a white dwarf star...

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    Debris from Disintegrating Planets Hurtling into White Dwarfs across the Galaxy

    February 12, 2022, Categories  Astronomy/Space

    An impression of the high-mass X-ray binary called Cygnus X-1. It consists of a blue supergiant star (right) called HDE 226868, orbiting what is in all likelihood a black hole. The black hole is sucking gas from the blue star’s atmosphere, leading to the formation of an accretion disc around the black hole.

    The moment that debris from destroyed planets impacts the surface of a white dwarf star has been observed for the first time by astronomers at the University of Warwick.

    They have used Xrays to detect the rocky and gaseous material left behind by a planetary system after its host star dies as it collides and is consumed within the surface of the star.

    Published today (9 February) in the journal Nature, the results are the first direct measurement of the accretion of rocky mate...

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    How Stars form in the Smallest Galaxies

    August 15, 2020, Categories  Astronomy/Space

    Image: ESO
    Image: ESO

    The question of how small, dwarf galaxies have sustained the formation of new stars over the course of the Universe has long confounded the world’s astronomers. An international research team led by Lund University in Sweden has found that dormant small galaxies can slowly accumulate gas over many billions of years. When this gas suddenly collapses under its own weight, new stars are able to arise.

    There are around 2,000 billion galaxies in our Universe and, while our own Milky-Way encompasses between 200 and 400 billion stars, small dwarf galaxies contain only a thousand times less. How stars are formed in these tiny galaxies has long been shrouded in mystery.

    However, in a new study published in the research journal Monthly Notices of the Royal Astronomical Society, a resea...

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