在1572年，丹麦的天文学家Tycho Brahe观测并研究了恒星的爆发，如今被命名Tycho遗迹。4个多世纪过后，钱德拉所拍摄的遗迹图片展现了一个正在膨胀的拥有数百万碎片（绿色和红色）其中包含了许多快速移动壳体特别是高能电子的气泡。
恒星的碎片以超音速扩张，导致了两个X射线源发射了冲击波-一个从外面跑进恒星内部的气体中，另一个则回到碎片中。这些冲击波瞬间产生，很大程度上改变了气压和温度，好比一个由超音速飞机所制造的极端声震模型。
In 1572, the Danish astronomer Tycho Brahe observed and studied the explosion of a star that became known as Tycho's supernova. More than four centuries later, Chandra's image of the supernova remnant shows an expanding bubble of multimillion degree debris (green and red) inside a more rapidly moving shell of extremely high energy electrons (filamentary blue).
The supersonic expansion (about six million miles per hour) of the stellar debris has created two X-ray emitting shock waves - one moving outward into the interstellar gas, and another moving back into the debris. These shock waves produce sudden, large changes in pressure and temperature, like an extreme version of sonic booms produced by the supersonic motion of airplanes.
这张由钱德拉拍摄的假色超新星遗迹图片展现了由高能粒子（蓝色）和数以百万计的气体（红色/绿色）所产生X射线。在公元1006年，被认为是“新星”的一个天体突然出现在天空，并持续了数天，其亮度比金星还亮。1006超新星或者SN1006，也许是记录中最亮一颗超新星了。
This false-color Chandra image of a supernova remnant shows X-rays produced by high-energy particles (blue) and multimillion degree gas (red/green). In 1006 AD, what was thought to be a "new star" suddenly appeared in the sky and over the course of a few days became brighter than the planet Venus. The supernova of 1006, or SN 1006, may have been the brightest supernova on record.
X射线
X射线 可见光 红复合图
高能X射线
低能X射线
可见光
红外
使用NASA的钱德拉X射线天文台，科学家们已经获得一张极好的星系中的最年轻超新星遗迹图片。这个爆炸恒星碎片的新视野帮助天文学家解决了一个长期的疑惑—了解恒星是如何悲惨的结束其生命和测量宇宙膨胀。
在400多年前，天空观测者—包括了著名的天文学家Johannes Kepler —发现了夜晚天空中的一个明亮天体。自从天文望远镜还没被发明前，只能通过肉眼观测新星—起初亮度超过木星并维持了数周。
Using NASA's Chandra X-ray Observatory, scientists have created a stunning new image of one of the youngest supernova remnants in the galaxy. This new view of the debris of an exploded star helps astronomers solve a long-standing mystery, with implications for understanding how a star's life can end catastrophically and for gauging the expansion of the universe.
Over 400 years ago, sky watchers -- including the famous astronomer Johannes Kepler -- noticed a bright new object in the night sky. Since the telescope had not yet been invented, only the unaided eye could be used to watch as a new star that was initially brighter than Jupiter dimmed over the following weeks.
DEM L238和DEM L249是两个在大麦哲伦星云中的超新星遗迹。来自NASA的钱德拉和ESA的XMM-NEWTON天文台的X射线数据说明了恒星所产生的碎片区在被热核爆炸摧毁时还非常年轻。
DEM L238 and DEM L249 are two supernova remnants in the Large Magellanic Cloud. X-ray data from NASA's Chandra and ESA's XMM-Newton observatories suggest that the stars responsible for these debris fields were unusually young when they were destroyed by thermonuclear explosions.
这是一张DEM L238和钱德拉拍摄位于银河系的Ia超新星遗迹做成4格对照图片。Kepler遗迹的X射线发射源包含了一个类似DEM L238一样明亮的中心，同时Tycho遗迹的X射线发射和SN1006的一般都是非常均匀的。这些结果表明了恒星的爆炸形成的DEM L238和Kepler超新星遗迹比Tycho和SN1006遗迹年轻很多。
This 4-panel compares the Chandra image of DEM L238 with the Chandra image of 3 Type Ia supernova remnants located in the Milky Way. The X-ray emission for Kepler\'s remnant contains a bright central region similar to DEM L238, while the X-ray emission for Tycho\'s remnant and SN 1006 are generally much more uniform. These results suggest that the stars that exploded and caused the DEM L238 and Kepler supernova remnants were much younger than the stars that produced the Tycho and SN 1006 remnants.
自翻
[ 本帖最后由 江涛 于 2008-3-2 15:52 编辑 ] |
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江兄又出自翻作品了。