Science

Distant galaxy threatened by 'death star'

The powerful jet produced by a massive black hole is blasting away at a nearby galaxy, prompting researchers to dub it the "death star" for its destructive effect on planets in its path.

Thepowerful jet produced by a massive black hole is blasting away at a nearby galaxy, prompting researchers to dub it the "death star" forits destructive effect on planets in its path.

Researchers said the jet being spewed by the black hole is anevent of "never-before witnessed galactic violence" that may have a profound effect on anything in its way.

"We've seen many jets produced by black holes, but this is the first time we've seen one punch into another galaxy like we're seeing here," said Dan Evans, a scientist at the Harvard-Smithsonian Center for Astrophysics and leader of the study. "This jet could be causing all sorts of problems for the smaller galaxy it is pummelling."

Jets from large black holes produce high amounts of radiation, especially high-energy X-rays and gamma rays, which can be lethal in large quantities. The combined effects of the radiation and particles travelling at almost the speed of light could severely damage the atmospheres of planets lying in the path of the jet, the researchers said. The jet could destroy the protective layers of ozone in the upper atmosphere of a planet.

The jet's effect on the neighbouring galaxy is likely to be substantial, the researchers said, because the two are relatively close together. They are only about 20,000 light years apart, or the same distance that Earth is from the centre of the Milky Way.

The system in which the two galaxies are found is known as 3C321. Its "death star" effect, a reference to the space weapon in the Star Wars movies, was discovered through both space and ground-based telescopes, includingNASA's Chandra X-ray Observatory, Hubble Space Telescope and Spitzer Space Telescope. The Very Large Array telescope in Socorro, N.M., and the Multi-Element Radio Linked Interferometer Network (MERLIN) telescopes in the United Kingdom were also used.

The studies will appear in an upcoming issue of the Astrophysical Journal.

The researchers said the massive influx of energy and radiation could also induce the formation of stars and planets after its initial wake of destruction is complete.

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