Distant ‘binge-eating’ black hole observed

The X-ray jet streaming from a binge-eating black hole in the nearby galaxy of Andromeda has been detected, U.S. and European astronomers say.

Classified as an ultraluminous X-ray source or ULX, the object is only the second ever seen in Andromeda, also known as M31, and was the target of an intense observing campaign by orbiting X-ray telescopes and radio observatories on the ground, NASA reported Wednesday.

Astronomers say they believe a ULX is a binary system containing a black hole that is rapidly consuming gas from its stellar companion at a rate very near a theoretical maximum, a feeding frenzy that astronomers say they do not yet fully understand.

“There are four black hole binaries within our own galaxy that have been observed accreting at these extreme rates,” Matthew Middleton at the Anton Pannekoek Astronomical Institute in Amsterdam said. “Gas and dust in our own galaxy interfere with our ability to probe how matter flows into ULXs, so our best glimpse of these processes comes from sources located out of the plane of our galaxy, such as those in M31.”

As gas is pulled into a black hole, it undergoes compression and heating, eventually becoming so hot it emits X-rays. The X-ray brightness is a good measure of the rate a black hole is consuming its stellar companion, astronomers said.

At some point the X-ray emission becomes so strong it pushes back on the inflowing gas, creating a theoretical limit on the black hole‘s accretion rate, they said.

“The discovery of jets tells us that this particular ULX is a typical stellar remnant about 10 times the mass of the sun, swallowing as much material as it possibly can,” Middleton said. “We may well find jets in ULXs with similar X-ray properties in other nearby galaxies, which will help us better understand the nature of these incredible outflows.” (UPI)



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안드로메다 근처서 ‘괴물’ 블랙홀 포착돼


안드로메다 은하계 근처에서 모든 것을 닥치는 대로 먹어 치우는 블랙홀의 신호가 포착됐다고 미국과 유럽 천문학자들이 발표했다.

초고광도 엑스레이원(ULX)로 분류된 이 존재는 안드로메다 은하계 인근에서는 두 번째로 발표된 것이라고 미항공우주국(NASA)가 수요일 보도했다.

천문학자들에 따르면 ULX 등급의 블랙홀은 주변 성단의 가스층을 이론적으로 가능한 최대속도로 먹어 치우는 것으로 알려졌으며 아직 그에 대해 연구된 바가 많지 않다.

가스가 블랙홀에 흡수되면 압착과 열기를 받아 엑스선을 방출하는 초고열 형태로 변모하며, 이 엑스선의 밝기를 통해 블랙홀이 주변 성단을 흡수하는 속도를 측정할 수 있다고 천문학자들은 설명했다.

이번에 포착된 엑스선을 통해 이 ULX 블랙홀이 우리 태양의 10배에 달하는 거대한 천체의 일부였다는 사실을 알 수 있었으며 이를 바탕으로 우주에 산재하는 엄청난 블랙홀들의 특성에 대해 더 잘 이해할 수 있는 계기가 됐다고 연구진은 덧붙였다. (코리아헤럴드)