Scientists Discover Milky Way's Youngest Exploding Star (1/2）

Astronomers using NASA's Chandra X-ray Observatory and the Very Large Array radio telescope in New Mexico have discovered the remains of a supernova, known as "G1.9", which must have lit up our galaxy with a bright flash of light about 140 years ago.

At a NASA news conference Wednesday, scientists said they were able to estimate the age of the supernova by tracking its remnant's rate of expansion over the last 20 years. They say it expanded by 16 percent - a surprisingly large amount - indicating it is much younger than previously thought.

The scientist who led the study, Stephen Reynolds of North Carolina State University, said radio and X-ray technology allowed scientists to track the dying star through a dense field of gas and dust that had previously obscured the view.

The second most recent supernova is believed to have occurred around 1680. Ever since astronomers discovered that supernova more than 50 years ago, they have been searching for more "missing" supernovae and their remnants. Reynolds explains that scientists have measured the rates of exploding stars in other galaxies, and found out that our own Milky Way galaxy seems to be lagging behind in the number of supernovae per century.

参考译文：

天文学家利用美国宇航局的钱德拉X射线天文台和位于新墨西哥州的一个巨阵射电望远镜发现了一颗超新星的残骸，这颗叫做"G1.9"的超新星在140年前用绚丽夺目的光芒点燃了我们的银河系。

在星期三的宇航局新闻发布会上，科学家说他们可以通过追踪过去20年中超新星残骸的膨胀速率来估算它的年龄。他们说该超新星以惊人的16%的速度膨胀，表明它比先前预想的年轻得多。

领导这项研究的科学家，北方卡罗莱纳州国立大学的斯蒂芬.雷诺兹说，无线电波和X射线技术使得科学家能穿透原先遮挡视线的浓厚气体和粉尘区域来跟踪垂死的星体。

第二个最新产生的超新星据说在1680年左右就存在了。天文学家已经发现那颗超新星50多年了，他们仍一直在寻找更多失踪的超新星和它们的残骸。雷诺兹解释说科学家已经测得爆炸星体在其他银河系的速度，而且发现我们的银河系每个世纪产生超新星的数量要落后其他银河系。

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