Galaxy

A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek galaxias, literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 million stars, range in size from dwarfs with less than a hundred million stars, to the largest galaxies known – supergiants with one hundred trillion stars, each orbiting its galaxy's center of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few percent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies. Galaxies are categorized according to their visual morphology as elliptical, spiral, or irregular. Many are thought to have supermassive black holes at their centers. The Milky Way's central black hole, known as Sagittarius A, has a mass four million times greater than the Sun.

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Astrophysicists explore our galaxy's magnetic turbulence in unprecedented detail using a new computer model

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Our galaxy's swirling gases and magnetic lines create cosmic artwork in new simulation

Not one, but two massive black holes are eating away at this galaxy

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Astrophysicists explore our galaxy's magnetic turbulence in unprecedented detail using a new computer model

Scientists precisely simulate turbulence in the Galaxy — it doesn’t behave like they thought - e3.eurekalert.org

Scientists precisely simulate turbulence in the Galaxy — it doesn’t behave like they thought - EurekAlert!

Astrophysicists explore our galaxy’s magnetic turbulence in unprecedented detail using a new computer model - EurekAlert!

Was a famous supernova an alien invader from another galaxy?

A star has been destroyed by a wandering supermassive black hole | Second supermassive black hole is a long way from the galaxy's core.

The Galaxy That Devoured Its Neighbors – And the Tiny One That Escaped

What Is a Galaxy?

Not one, but two massive black holes are eating away at this galaxy