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Dwarf Galaxy Could Be an Ejected Black Hole

By David Reneke

Astronomers have observed what could be a massive black hole that has been ejected into space after two galaxies collided.

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Dwarf Galaxy Could Be an Ejected Black Hole

Astronomers have observed a mysterious phenomenon that could be a massive black hole that has been ejected into space in connection with two galaxies colliding. This may be due to gravitational waves from the collision.

If two galaxies are on a collision course and eventually collide, they will merge into a single larger galaxy. At the centre of each galaxy is a massive black hole and they will also merge. If gravitational waves have been formed in the process, spreading out into space, there might be a recoiling effect, causing one of the two black holes to be ejected.

In some cases, the recoil effect is relatively weak and the black hole is pulled back to the centre. In other cases, the recoil effect is so strong that the black hole is flung out of the galaxy forever.

Astronomers have long been searching for such recoil effects, and now they believe they’ve found one. It’s a black hole located 90 million light years from Earth, relatively close by.

An international team of researchers from the universities of Hawaii and Copenhagen have made observations with one of the largest telescopes in the world at the Keck Observatory in Hawaii. Using a technique called adaptive optics, which can compensate for disturbances from the atmosphere, it’s now possible to obtain precise observations with...

The full text of this article can be purchased from Informit.