哈勃捕捉到一死亡恒星附近的气体碰撞

夜空

EMBARGOED UNTIL:  April 15, 1996

PHOTO NO.: STScI-PRC96-13a


HUBBLE CAPTURES COLLISION OF GASES NEAR DYING STAR
[哈勃捕捉到一死亡恒星附近的气体碰撞]

This colorful image from the Hubble Space Telescope shows the
collision of two gases near a dying star.  Astronomers have dubbed
the tadpole-like objects in the upper right-hand corner "cometary
knots" because their glowing heads and gossamer tails resemble
comets.  Although astronomers have seen gaseous knots through
ground-based telescopes, they have never seen so many in a single
nebula.

Hubble captured thousands of these knots from a doomed star in the
Helix nebula, the closest planetary nebula to Earth at 450 light-years
away in the constellation Aquarius.  Each gaseous head is at least
twice the size of our solar system; each tail stretches 100 billion
miles, about 1,000 times the Earth's distance to the Sun.  The most
visible gaseous fragments lie along the inner edge of the star's ring,
trillions of miles from the star at its center.  The comet-like tails
form a radial pattern around the star like the spokes on a wagon
wheel. Astronomers have seen the spoke pattern using ground-based
telescopes, but Hubble reveals for the first time the sources of
these objects.

Astronomers theorize that the gaseous knots are the results of a
collision between gases. The doomed star spews the hot gas from
its surface, which collides with the cooler gas that it had ejected
10,000 years before. The crash fragments the smooth cloud
surrounding the star into smaller, denser finger-like droplets, like
dripping paint.  Astronomers expect the gaseous knots, each several
billion miles across, to eventually dissipate into the cold blackness
of interstellar space.

This image was taken in August, 1994 with Hubble's Wide Field
Planetary Camera 2.  The red light depicts nitrogen emission
([NII] 6584A); green, hydrogen (H-alpha, 6563A); and blue,
oxygen (5007A).

Credit:  Robert O'Dell, Kerry P. Handron (Rice University,
Houston, Texas) and NASA

Image files in GIF and JPEG format and captions may be accessed
on Internet via anonymous ftp from oposite.stsci.edu in /pubinfo.

                         GIF             JPEG
PRC96-13a  Helix Nebula  gif/HelixF.gif  jpeg/HelixF.jpg

Higher resolution digital versions (300dpi JPEG) of the release
photographs will be available temporarily in /pubinfo/hrtemp:
96-13a.jpg (color) and 96-13aBW.jpg (black/white).   

GIF and JPEG images, captions and press release text are available
via World Wide Web at http://www.stsci.edu/pubinfo/PR/96/13.html
and via links in http://www.stsci.edu/pubinfo/Latest.html or
http://www.stsci.edu/pubinfo/Pictures.html.

从哈勃太空望远镜拍摄的彩色图像显示了在一垂死恒星附近的两股相撞的气体。天文学家称右上角那蝌蚪状的物体彗星结，因为他们那炽热的头部和细丝状的尾部像彗星。尽管天文学家曾经通过地面望远镜看过这类的气体结，但他们还未曾在单一的星云里看到如此之多的气体结。
    哈勃在一个旋涡星云里一颗死亡恒星上捕捉到成千上万的这种气体结，离地球最近的行星状星云，450光年之外的水瓶座。每个气体头的大小至少是我们太阳系的两倍;每个气体的尾部延伸到一千亿英里之外,大约是一百倍的日地距离.最明显的气体碎块都在星体附近的环形内,以万亿英里远处的恒星为中心. 该彗星般的尾巴从恒星周围辐射出去,就像一个货车车轮.
    天文学家所看到的是利用地面望远镜,但哈勃首次发现这些物体的来源.
    天文学家推测这些气体结形成于气体之间的碰撞:从死亡的恒星表面喷出炽热气体与它在10000万年前所喷出的较冷气体相碰撞.在星体附近的那些碰撞出来的碎片、那些小块的云，变成小块的，稠密的，手指状的微滴，就像一滴滴的颜料天文学家预想这些气体结,每个都横跨越数十亿英里,最终会消散于黑暗寒冷的星际空间.

[ 本帖最后由 夜空 于 2006-3-3 04:38 PM 编辑 ]

夜猫子

这张图似乎在哪里见过，但这么详细的说明还是第一次见。还得感谢夜空斑竹的翻译，呵呵！

夜空

是我从电驴上拉回来的，这类图片还有很多，我会慢慢把他们都翻译过来的，大家耐心的等等:lol

夜猫子

好，再顶！