The astronomers said the stellar black hole may have been created by an exploding star in the inner disk of the Milky Way. The black hole is 6,000 to 9,000 light years away, the researchers said. A report on the observations appears Tuesday in the journal Astronomy and Astrophysics.
A black hole is a point in space that is so dense with matter that its gravitational field will not let anything - not even light - escape. Stellar black holes, equal to 3.5 to about 15 solar masses, can be formed by the collapse of a single massive star. But galactic black holes, such as those in NGC6240, are much larger, equal perhaps to millions of solar masses, and are usually at the center of galaxies.The Milky Way, home galaxy of the sun and its planets, is thought to have a black hole at its center.With its immense gravitational pull, a black hole can suck in gas, dust and other matter from the surrounding space. Entire stars can be stripped and pulled into the bottomless maw. As it spirals in at near light speeds, matter captured by a black hole heats by millions of degrees and gives out intense radiation in several parts of the spectrum, including X-rays. The orbiting Chandra observatory is able to detect these X-rays and relay the data to Earth for study by astronomers. 黑洞就是太空中的一个点，此点密度甚高，使得任何物质甚至光都无法脱离它的引力。一个巨星的瓦解就足以产生质量相当于3.5至15个太阳的星球黑洞。但星系黑洞如NGC6240中的黑洞要大得多，质量相当于几百万个太阳，通常位于星系的中心。 银河系是太阳及其九大行星的家，科学家认为银河系的中心就存在着一个黑洞。靠着强大的引力牵拉，黑洞能吸入来自周围空间的气体、尘埃和其它物质。这个无底洞甚至将整个星球分解后吸入。物质被黑洞捕获后以几近光速的高速被旋转吸入洞中时，它所释放出的热量可高达几百万度，并可发出不同的强烈射线，包括X射线。正在轨道上运转的钱德拉望远镜可以检测到这些X射线，并将数据传回地球，供天文学家研究。
