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Astronomy & Space vocabulary · Stars & Stellar Evolution

White dwarf

Meaning in astronomy & space, with examples

nounCommon term

In astronomy & space, white dwarf means: The small, very dense and hot core left behind when a Sun-like star dies. It is about the size of Earth but has a mass comparable to the Sun's.

In Turkish: beyaz cüce

How it is used

Common in explanations of stellar evolution. A white dwarf no longer produces energy by fusion; it slowly cools over billions of years. Sirius B, the faint companion of Sirius, is a famous example.

Example sentences

  1. Our Sun will end its life as a white dwarf surrounded by a planetary nebula.

  2. A teaspoon of white dwarf material would weigh several tonnes on Earth.

Common collocations

  • white dwarf star
  • cooling white dwarf
  • become a white dwarf
  • red giantA large, cool and very bright star in a late stage of its life. It forms when a star like the Sun uses up the hydrogen in its core and its outer layers swell.
  • neutron starThe extremely dense core left after a massive star explodes as a supernova. It packs more mass than the Sun into a ball only about 20 kilometres across.
  • nebulaA huge cloud of gas and dust in space. Some nebulae are places where new stars are born; others are material thrown off by dying stars.
  • supernovaA huge stellar explosion that can briefly shine as brightly as a whole galaxy. It happens when a massive star collapses or when a white dwarf gains too much mass.
  • main sequenceThe long, stable stage of a star's life when it fuses hydrogen into helium in its core. On a chart of star brightness against temperature, these stars form a diagonal band.

More terms: Stars & Stellar Evolution

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