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This composite image shows a supernova within the galaxy M100 that may contain the youngest known black hole in our cosmic neighborhood. In this image, Chandra’s X-rays are colored gold, while optical data from ESO’s Very Large Telescope are shown in red, green, and blue, and infrared data from Spitzer are red. The location of the supernova, known as SN 1979C, is labeled.

SN 1979C was first reported to be seen by an amateur astronomer in 1979. The galaxy M100 is located in the Virgo Cluster about 50 million light years from Earth. This approximately 30-year age, plus its relatively close distance, makes SN 1979C the nearest example where the birth of a black hole has been observed, if the interpretation by the scientists is correct.

Data from Chandra, as well as NASA’s Swift, the European Space Agency’s XMM-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady for the 12 years from 1995 to 2007 over which it has been observed. This behavior and the X-ray spectrum, or distribution of X-rays with energy, support the idea that the object in SN 1979C is a black hole being fed either by material falling back into the black hole after the supernova, or from a binary companion.

The scientists think that SN 1979C formed when a star about 20 times more massive than the Sun collapsed. It was a particular type of supernova where the exploded star had ejected some, but not all of its outer, hydrogen-rich envelope before the explosion, so it is unlikely to have been associated with a gamma-ray burst (GRB). Supernovas have sometimes been associated with GRBs, but only where the exploded star had completely lost its hydrogen envelope. Since most black holes should form when the core of a star collapses and a gamma-ray burst is not produced, this may be the first time that the common way of making a black hole has been observed.

The very young age of about 30 years for the black hole is the observed value, that is the age of the remnant as it appears in the image. Astronomers quote ages in this way because of the observational nature of their field, where their knowledge of the Universe is based almost entirely on the electromagnetic radiation received by telescopes.

新浪科技讯 北京时间11月16日凌晨消息，据国外媒体报道，天文学家利用美国宇航局的钱德拉X射线望远镜发现地球附近最年轻的黑洞，这个黑洞形成只有30年，它为观测这类婴儿期天体提供了独一无二的机会。

这个形成只有30年的黑洞是距离地球约5000万光年的M100星系中的超新星SN 1979C的余烬，可以帮助科学家更好地理解大质量恒星是如何爆炸的，哪些恒星爆炸后留下的是黑洞还是中子星，以及我们这个星系和其他星系黑洞的数量。

从美国宇航局的钱德拉望远镜、欧洲航天局的XMM-Newton望远镜和德国ROSAT望远镜获得的数据显示一个明亮的X射线源，这个X射线源在1995年到2007年这段观测期内一直非常稳定。这显示这个天体是一个黑洞，正吞噬这颗超新星或一个双子伴星落下的物质。

美国马萨诸塞州剑桥哈佛-史密森天体物理学中心的丹尼尔-帕特诺德表示：“如果我们的解释没错的话，这是我们观测到的最近的一个黑洞诞生的实例。”

超新星SN 1979C发现于1979年。科学家认为，它是一颗质量相当于太阳20倍的恒星坍塌后形成的。以前，科学家通过伽玛射线爆发，探测到遥远宇宙中的许多新黑 洞，但SN 1979C不同，因为它距离地球更近，属于一颗不太可能与伽玛放线爆发有联系的超新星。相关的理论预测，宇宙中的黑洞应该是在恒星的星核坍塌后形成的，而 且也不会发出伽玛射线。

剑桥哈佛-史密森天体物理学中心的研究人员亚伯拉罕-朗布表示：“这可能不是我们首次观测到黑洞以我们常见的方式形成，但探测到这种类型的黑洞难度极大，因为需要对X射线进行数十年的观测才行。”

新发现的这一黑洞的观测年龄只有大约30岁，这个观点与最近天文学界提出的理论是一致的。2005年，天文学家提出，这个超新星的明亮的光由一 个黑洞的喷射流推动，而这个黑洞无法穿透这颗恒星的“氢外罩”，形成伽玛射线爆发。对SN 1979C的观测结果符合这一理论。

尽管有证据证明SN 1979C中有一个新形成的黑洞，但研究人员也在考虑另一种很吸引人的可能性：这些X射线可能是一颗带有高能粒子的快速旋转的中子星发出的。如果是这样的 话，SN 1979C中的这个天体将是迄今为止观测到的最年轻最明亮的“脉冲风星云”，是已知最年轻的中子星。而在此之前已知的明亮的脉冲风星云—-蟹状星云约 有950岁。

此前曾有媒体大肆宣称NASA的此次宣布的发现“足以震惊全人类”，引发网友广泛关注,钱德拉望远镜的官方网站也因为访问量过大无法访问。(孝文)