通过探索围绕在一颗正在死亡恒星周围的正在成长的气体与尘埃所组成的气泡，NASA的哈勃空间望远镜展示了一个以前从未被发现过的丰富结构。
这个天体，叫做NGC2371，一个行星状星云，是一颗正在成长类太阳恒星的遗迹。在NGC2371中心可见的恒星遗迹是红巨星非常热的核心，现在被剥去了外层。其表面温度达到华氏240000度。NGC2371位于距双子座大约4300光年的地方。
哈勃拍的图片展示了几个值得注意的特征，位于中心恒星相反位置的非常引人注意的粉红色星云。这个颜色表明与余下的其他星云比起来，温度相对比较低，密度也相对较大。
尽管撞击是常有的，，非常小的粉红色圆点，标志着位于恒星完全相反一侧的相对密度较高的气体聚集物。这个特征表明了来自恒星的气体是从一个特殊方向发射的。喷射的方向已经在过去几千年中被改变了。对于此行为的原因现在还不是太清楚，但也许和第2颗围绕中心可见恒星运转的恒星的存在有关系。
行星状星云一个由来自中心濒临死亡恒星所释放出的气体组成的正在膨胀的星云。星云的膨胀是因为受到来自中心热恒星遗迹的紫外辐射。在仅仅的几千年里，星云将消散在太空中，中心的恒星将完全冷却下来，最后变成白矮星，这是几乎所有恒星演化的最后阶段。
哈勃拍的NGC2371是张假色合成的图象，通过率光片阻止来自S N（红色），H（绿色）和O（蓝色）。这张图片是由哈勃的大视场行星成相仪2在2007年11月拍摄的，作为哈勃的传统项目。
Probing a glowing bubble of gas and dust encircling a dying star, NASA's Hubble Space Telescope reveals a wealth of previously unseen structures.
The object, called NGC 2371, is a planetary nebula, the glowing remains of a sun-like star. The remnant star visible at the center of NGC 2371 is the super-hot core of the former red giant, now stripped of its outer layers. Its surface temperature is a scorching 240,000 degrees Fahrenheit. NGC 2371 lies about 4,300 light-years away in the constellation Gemini.
The Hubble image reveals several remarkable features, most notably the prominent pink clouds lying on opposite sides of the central star. This color indicates that they are relatively cool and dense, compared to the rest of the gas in the nebula.
Also striking are the numerous, very small pink dots, marking relatively dense and small knots of gas, which also lie on diametrically opposite sides of the star. These features appear to represent the ejection of gas from the star along a specific direction. The jet's direction has changed with time over the past few thousand years. The reason for this behavior is not well understood, but might be related to the possible presence of a second star orbiting the visible central star.
A planetary nebula is an expanding cloud of gas ejected from a star that is nearing the end of its life. The nebula glows because of ultraviolet radiation from the hot remnant star at its center. In only a few thousand years the nebula will dissipate into space. The central star will then gradually cool down, eventually becoming a white dwarf, the final stage of evolution for nearly all stars.
The Hubble picture of NGC 2371 is a false-color image, prepared from exposures taken through filters that detect light from sulfur and nitrogen (red), hydrogen (green), and oxygen (blue). These images were taken with Hubble's Wide Field Planetary Camera 2 in November 2007, as part of the Hubble Heritage program.
URL：http://spacespin.org/mediagaller ... s=20080304233206319
自翻，由于翻的比较匆忙，所以质量不高，见谅
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