w****l
发帖数: 344 | 1 http://www.phys.ncku.edu.tw/~astrolab/mirrors/apod/image/0301/abell1689_hstacs_c1
.jpg
影像提供: N. Benitez (JHU), T. Broadhurst (Hebrew Univ.), H. Ford (JHU),
M. Clampin(STScI),
G. Hartig (STScI), G. Illingworth (UCO/Lick), ACS Science Team, ESA, NASA
說明: 離我們二十億光年遠的星系團Abell 1689，是宇宙中最大質量的天體之一。
在上面這幅由哈伯望遠鏡先進巡天相機所拍攝的影像裡，Abell 1689正如同愛因斯坦
重力理論所預測的，扭曲了它後面星系所發出的光，產生了多個變形的影像。 天體
巨大重力透鏡效應的強度和它的質量有關，不過影像中這群泛黃星系的可見物質，只
佔造成這些背景星系弧狀影像所需要質量的百分之一而已！ 事實上，造成這種宇宙
空間扭曲，並產生這種重力透鏡效應的大部份質量，是一種仍然很神祕的暗物質。
我們會知道星團的主要重力來源 |
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s*****t
发帖数: 1994 | 2 Abell 1689 Warps Space
Credit: N. Benitez (JHU), T. Broadhurst (Hebrew Univ.), H. Ford (JHU), M.
Clampin(STScI),
G. Hartig (STScI), G. Illingworth (UCO/Lick), ACS Science Team, ESA, NASA
Explanation: Two billion light-years away, galaxy cluster Abell 1689 is one of the most
massive objects in the Universe. In this view from the Hubble Space Telescope's Advanced
Camera for Surveys, Abell 1689 is seen to warp space as predicted by Einstein's theory of
gravity -- |
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s*****t
发帖数: 1994 | 3 Light Echoes from V838 Mon
Credit: H. Bond (STScI), A. Henden (USNO Flagstaff), Z. Levay (STScI), et al., ESA,
NASA
Explanation: Nominated for most mysterious star in the Milky Way, V838 Monocerotis
briefly became one of the brightest stars in our galaxy. Its outburst discovered in January
2002, observations have indicated that V838 Mon somehow transformed itself over a period
of months from a small under-luminous star a little hotter than the Sun, to a
highly-lum |
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s*****t
发帖数: 1994 | 4 V838 Light Echo: The Movie
Credit: H. Bond (STScI), A. Henden (USNO Flagstaff), Z. Levay (STScI), et al., ESA,
NASA
Explanation: What caused this outburst of V838 Mon? For reasons unknown, star V838
Mon's outer surface suddenly greatly expanded with the result that it became the brightest star
in the entire Milky Way Galaxy. Then, just as suddenly, it faded. A stellar flash like this has
never been seen before -- supernovas and novas expel matter out into space. A |
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s*****t
发帖数: 1994 | 5 The Egg Nebula in Polarized Light
Credit: Hubble Heritage Team (STScI/AURA), W. Sparks (STScI) & R. Sahai (JPL), NASA
Explanation: Where is the center of the unusual Egg Nebula? Like a baby chick pecking its
way out of an egg, the star in the center of the Egg Nebula is casting away shells of gas and dust
as it slowly transforms itself into a white dwarf star. The Egg Nebula is a rapidly evolving
pre-planetary nebula spanning about one light year toward the constellation of Cygnus. Thick
dust, t |
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s*****t
发帖数: 1994 | 6 Warped Spiral Galaxy ESO 510-13
Credit: Hubble Heritage Team (STScI / AURA), C. Conselice (U. Wisconsin / STScI) et al.,
NASA
Explanation: How did spiral galaxy ESO 510-13 get bent out of shape? The disks of many
spirals are thin and flat, but not solid. Spiral disks are loose conglomerations of billions of
stars and diffuse gas all gravitationally orbiting a galaxy center. A flat disk is thought to be
created by sticky collisions of large gas clouds early in the gal |
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s*****t
发帖数: 1994 | 7 Disappearing Clouds in Carina
Credit: Hubble Heritage Team (STScI/AURA), N. Walborn (STScI) & R. Barb_ (La Plata
Obs.), NASA
Explanation: This dense cloud of gas and dust is being deleted. Likely, within a few million
years, the intense light from bright stars will have boiled it away completely. Stars not yet
formed in the molecular cloud's interior will then stop growing. The cloud has broken off of
part of the greater Carina Nebula, a star forming region about 8000 |
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w****l
发帖数: 344 | 8 http://www.phys.ncku.edu.tw/~astrolab/mirrors/apod/image/0301/abell1689_hstacs_c1
.jpg
影像提供: N. Benitez (JHU), T. Broadhurst (Hebrew Univ.), H. Ford (JHU),
M. Clampin(STScI),
G. Hartig (STScI), G. Illingworth (UCO/Lick), ACS Science Team, ESA, NASA
說明: 離我們二十億光年遠的星系團Abell 1689，是宇宙中最大質量的天體之一。
在上面這幅由哈伯望遠鏡先進巡天相機所拍攝的影像裡，Abell 1689正如同愛因斯坦
重力理論所預測的，扭曲了它後面星系所發出的光，產生了多個變形的影像。 天體
巨大重力透鏡效應的強度和它的質量有關，不過影像中這群泛黃星系的可見物質，只
佔造成這些背景星系弧狀影像所需要質量的百分之一而已！ 事實上，造成這種宇宙
空間扭曲，並產生這種重力透鏡效應的大部份質量，是一種仍然很神祕的暗物質。
我們會知道星團的主要重力來源 |
|
s*****t
发帖数: 1994 | 9 Abell 1689 Warps Space
Credit: N. Benitez (JHU), T. Broadhurst (Hebrew Univ.), H. Ford (JHU), M.
Clampin(STScI),
G. Hartig (STScI), G. Illingworth (UCO/Lick), ACS Science Team, ESA, NASA
Explanation: Two billion light-years away, galaxy cluster Abell 1689 is one of the most
massive objects in the Universe. In this view from the Hubble Space Telescope's Advanced
Camera for Surveys, Abell 1689 is seen to warp space as predicted by Einstein's theory of
gravity -- |
|
s*****t
发帖数: 1994 | 10 Light Echoes from V838 Mon
Credit: H. Bond (STScI), A. Henden (USNO Flagstaff), Z. Levay (STScI), et al., ESA,
NASA
Explanation: Nominated for most mysterious star in the Milky Way, V838 Monocerotis
briefly became one of the brightest stars in our galaxy. Its outburst discovered in January
2002, observations have indicated that V838 Mon somehow transformed itself over a period
of months from a small under-luminous star a little hotter than the Sun, to a
highly-lum |
|
s*****t
发帖数: 1994 | 11 V838 Light Echo: The Movie
Credit: H. Bond (STScI), A. Henden (USNO Flagstaff), Z. Levay (STScI), et al., ESA,
NASA
Explanation: What caused this outburst of V838 Mon? For reasons unknown, star V838
Mon's outer surface suddenly greatly expanded with the result that it became the brightest star
in the entire Milky Way Galaxy. Then, just as suddenly, it faded. A stellar flash like this has
never been seen before -- supernovas and novas expel matter out into space. A |
|
s*****t
发帖数: 1994 | 12 The Egg Nebula in Polarized Light
Credit: Hubble Heritage Team (STScI/AURA), W. Sparks (STScI) & R. Sahai (JPL), NASA
Explanation: Where is the center of the unusual Egg Nebula? Like a baby chick pecking its
way out of an egg, the star in the center of the Egg Nebula is casting away shells of gas and dust
as it slowly transforms itself into a white dwarf star. The Egg Nebula is a rapidly evolving
pre-planetary nebula spanning about one light year toward the constellation of Cygnus. Thick
dust, t |
|
s*****t
发帖数: 1994 | 13 Warped Spiral Galaxy ESO 510-13
Credit: Hubble Heritage Team (STScI / AURA), C. Conselice (U. Wisconsin / STScI) et al.,
NASA
Explanation: How did spiral galaxy ESO 510-13 get bent out of shape? The disks of many
spirals are thin and flat, but not solid. Spiral disks are loose conglomerations of billions of
stars and diffuse gas all gravitationally orbiting a galaxy center. A flat disk is thought to be
created by sticky collisions of large gas clouds early in the gal |
|
s*****t
发帖数: 1994 | 14 Disappearing Clouds in Carina
Credit: Hubble Heritage Team (STScI/AURA), N. Walborn (STScI) & R. Barb_ (La Plata
Obs.), NASA
Explanation: This dense cloud of gas and dust is being deleted. Likely, within a few million
years, the intense light from bright stars will have boiled it away completely. Stars not yet
formed in the molecular cloud's interior will then stop growing. The cloud has broken off of
part of the greater Carina Nebula, a star forming region about 8000 |
|
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m***r
发帖数: 1801 | 16 Astrophysics PhDs had, are having, and will have quite some difficulties
finding real jobs. Since the tenure track positions are so few. This year
is a better year, but about 20 or so only. If you are so into science and
couldn't find a tenure track for now, definitely continue for a next postdoc
, in a place like CFA or STScI or NRAO, so you'll have more connections and
get the next term.
That said, many of my classmates from undergrad came to the states, started
as an astrophysics phd, and ... 阅读全帖 |
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f*r
发帖数: 3968 | 17 哈勃发现前所未有的激波
译：Jack
这张全新的哈勃照片向我们展示了正在形成行星状星云的原行星状星云。一垂死的恒
星（位于星云中央，隐藏在尘埃和气体之后）喷出大量的气体。一部分气体可以达到每小
时50-100万公里的高速。
蓝色的光源自超生激波与周围的物质相碰撞激发的氢和电离氮。这张图片第一次展示
了星云前所未有的复杂结构。
这张图片在四块不同的滤镜下由宽视场行星照相机2摄于2000年圣诞节。红色的光波
长为791nm（曝光900s），红色的为675nm（曝光900s），同时混合氢的光（656nm）和电
离氮的光（658nm）而成蓝光（曝光14700s）。
版权：ESA和Valentin Bujarrabal
天体类型：星云
天体：葫芦星云
设备：宽视场行星照相机2
译自 哈勃网站（http://oposite.stsci.edu）
▲ BACK |
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f*r
发帖数: 3968 | 18 NGC 2440（英文原文）
译：Jack
NGC 2440是另一个行星状星云，但它较NGC 2346有更加复杂的结构。NGC 2440的中央
星是已知最热的恒星之一，表面温度大约200，000摄氏度。其周围星云的复杂结构暗示天
文学家那儿存在源自中央星的周期性的喷射，有点类似NGC 2346。但是对于NGC 2440，每
次喷射的方向是不确定。同时，星云中充满着尘埃云，它们形成了从中央星向外辐射的暗
而长的条纹。另外，对于其中明亮的星云，是由于受中央星辐射的紫外线激发所至。NGC
2440被一个大而冷的星云所包围，它在一般的望远镜中是不可见，但在红外望远镜中却可
以被探测到。NGC 2440坐落在距地球4，000光年的船尾座内。
此照片由哈勃Heritage小组获得。
译自 哈勃网站（http://oposite.stsci.edu）
NGC 2440
（Chinese Version）
NGC 2440 is another planetary nebula ejected by a dying star, but it has |
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f*r
发帖数: 3968 | 19 “斯宾若格拉芙”星云（英文原文）
译：Jack
像一颗精心雕琢的宝石，行星状星云IC 418坐落在距地球2，000光年的天兔座内。这
张照片是哈勃太空望远镜的宽视场行星照相机2 近期拍摄的照片之一。
行星状星云是类似于太阳的恒星的演化归宿。IC 418中央的恒星在几千年前是一颗红
巨星，但之后它便抛射出它的外壳，形成了星云，现今它的直径已达到约0.1光年左右。
星云中心的恒星遗迹是红巨星炽热的核，从那儿发射出的紫外线激发周围的气体使之发射
出荧光。在以后的数千年中，这个星云会逐渐的解体，并且这颗恒星在其后的几十亿年中
会渐渐地冷却进而变成一颗白矮星。我们的太阳注定也会有同样的命运，但那时50亿年之
后的事了。
这是一张伪彩色的照片，使用宽视场行星照相机2 摄于1999年9月。红色代表离子氮
的发射（星云中最冷的气体），绿色代表氢的发射，蓝色代表离子氧的发射（星云中最热
的气体，最靠近中央的恒星）。在星云中出现的这些惊人的结构是全新的，它们的形成原
因还不为人所知。
译自 哈勃网站（http://oposite.stsci |
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f*r
发帖数: 3968 | 20 蝴蝶状的“派碧隆”（Papillon）星云揭示大质量恒星诞生之谜（英文原文）
译：Jack
NASA哈勃太空望远镜对位于N159中的恒星诞生区进行了观测，N159坐落在离我们170
，000光年远的伴星系——大麦哲伦星云中。其中，来自新生大质量恒星的星风奔流着穿
过大星云中的脊状和丝状结构。
译自 哈勃网站（http://oposite.stsci.edu）
A Butterfly-Shaped "Papillon" Nebula Yields Secrets of Massive Star Birth
（Chinese Version）
A NASA Hubble Space Telescope view of a turbulent cauldron of starbirth,
called N159, taking place 170,000 light-years away in our satellite galaxy,
the Large Magellanic Cloud (LMC). Torrential stellar w |
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f*r
发帖数: 3968 | 21 木星和木卫一的罕见合影（英文原文）
译：Jack
这张照片，展示了1996年7月24日有着火山活动的木星卫星——木卫一正经过木星湍
动的云层的上方。木星上那个醒目的黑点是木卫一的阴影。这个影子的大小与木卫一的大
小（3640公里）相仿，它以每秒17公里的速度扫过木星的上空。
这张照片的分辨率大致为100英里。木卫一上的亮斑是二氧化硫的结晶区。木卫一与
月亮的大小差不多，但是却远了2000倍。
这是哈勃太空望远镜配合伽利略探测器而拍摄的一系列照片。尽管伽利略探测器可以
提供分辨率更高的图像，但哈勃却可以提供伽利略探测器无法看到的紫外波段的照片。
此照片使用宽视场行星照相机2在紫波段拍摄
译自 哈勃网站（http://oposite.stsci.edu）
Rare Hubble Portrait Of Io And Jupiter
（Chinese Version）
This image, shows Jupiter's volcanic moon Io passing above the turbulent
clouds of t |
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f*r
发帖数: 3968 | 22 我们的家——地球
译：Jack
在看了这么多的天体照片之后，让我们来看一下我们的家——地球。这是一张地球的
全景照片，由环境应用同步卫星GOES-8于世界时1999年9月2日18时拍摄。
另一张照片是出现在南中国海的台风。
译自 哈勃网站（http://oposite.stsci.edu）
▲ BACK |
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s*****t
发帖数: 1994 | 23 The Colors and Mysteries of Centaurus A
Credit: X-ray (NASA/CXC/M. Karovska et al.); Radio 21-cm image
(NRAO/VLA/Schiminovich, et al.),
Radio continuum image (NRAO/VLA/J.Condon et al.); Optical (Digitized Sky Survey, U.K.
Schmidt Image/ STScI)
Explanation: Why is spiral galaxy Centaurus A in so much turmoil? The above composite
image shows different clues to the unusual galaxy's past in different bands of light. In low
energy radio waves, sh |
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s*****t
发帖数: 1994 | 24 Spiral Galaxy NGC 7742
Credit : Hubble Heritage Team (AURA/ STScI/ NASA)
Explanation: This might resemble a fried egg you've had for breakfast, but it's actually much
larger. In fact, ringed by blue-tinted star forming regions and faintly visible spiral arms, the
yolk-yellow center of this face-on spiral galaxy, NGC 7742, is about 3,000 light-years across.
About 72 million light-years away in the constellation Pegasus, NGC 7742 is known to be a
Seyfert galaxy - a type of active spir |
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s*****t
发帖数: 1994 | 25 The Hubble Deep Field
Credit: R. Williams, The HDF Team (STScI), NASA
Explanation: Galaxies like colorful pieces of candy fill the Hubble Deep Field - one of
humanity's most distant optical views of the Universe. The dimmest, some as faint as 30th
magnitude (about four billion times fainter than stars visible to the unaided eye), are very
distant galaxies and represent what the Universe looked like in the extreme past, perhaps
less than one billion years after the Big Bang. To make |
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s*****t
发帖数: 1994 | 26 Hoag's Object: A Strange Ring Galaxy
Credit: R. Lucas (STScI/AURA), Hubble Heritage Team, NASA
Explanation: Is this one galaxy or two? This question came to light in 1950 when
astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring
dominated by bright blue stars, while near the center lies a ball of much redder stars that are
likely much older. Between the two is a gap that appears almost completely dark. How Hoag's
Object formed remains unknown, alt |
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s*****t
发帖数: 1994 | 27 Ring Galaxy AM 0644-741 from Hubble
Image Credit: Hubble Heritage Team (AURA / STScI), J. Higdon (Cornell) ESA, NASA
Explanation: How could a galaxy become shaped like a ring? The rim of the blue galaxy pictured on the right is an immense ring-like structure 150,000 light years in diameter composed of newly formed, extremely bright, massive stars. That galaxy, AM
0644-741, is known as a ring galaxy and was caused by an immense galaxy collision. When galaxies collide, they pass through each other |
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w****l
发帖数: 344 | 28 木星 Jupiter [小百科首页]
哈伯太空望远镜, 1995.2. (C) NASA / STScI
木星是从太阳数来第五颗行星，也是太阳系最大的行星，它的轨道半径为77
,833万公里 (5.20AU)；赤道处直径为142,984公里；质量是1.900x1027公斤，超
过太阳系其它所有行星总合的2倍，是地球质量的318倍。
木星自史前时代就已为人所知，是全天第四亮的星体，仅次於太阳、月球和
金星之後，火星则在某些时候会比它亮。1610年，伽利略首先发现木星的四大卫
星－木卫一 (Io)、木卫二 (Europa)、木卫三 (Ganymede) 及木卫四 (Callisto
)，也就是着名的伽利略卫星，这是人类首度发现绝对不可能绕着地球运转的星体
，这是当时支持哥白尼的日心说最有力的证据之一。
1973年，先锋10号 (Pioneer 10)探测船首次造访木星，其後先锋11号 (Pio
neer 11)、航海家1、2号 (Voyager 1/2) 及尤利西斯号 (Ulysses) 也陆续到过
木星。新一代探测船伽利略号 (Galileo) 现正在木星轨道上，已传回许多极有价
值的资 |
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w****l
发帖数: 344 | 29 冥王星 Pluto [小百科首页]
哈伯太空望远镜, 1996.3. (C) NASA / STScI
冥王星是从太阳数来第九颗、目前已知离太阳最远的行星，也是太阳系最小的行星，
甚至太阳系中有七颗卫星都还比它大（分别是月球、木卫一、木卫二、木卫三、木卫四、
土卫六及海卫一）！冥王星的平均轨道半径为591,352万公里 (39.5AU)；直径为2,274公
里；质量是1.27x1022公斤。
由天王星及海王星的公转轨道异常，可预测出在海王星之外应该还有一颗行星的存在
，於是美国亚历桑那洲罗威尔天文台 (Lowell Observatory) 的 Clyde W. Tombaugh 在
经过非常绵密的研究和搜寻之後，终於在1930年找到了冥王星；但是这颗新行星的公转根
本和预测轨道不合，只在观测当时很接近预测的位置，再早一点或晚一点就不可能在预测
位置上找到它了，所以说冥王星的发现真是意料之外的幸运。
在冥王星被发现之後不久，大家就知道它实在是小得不足以解释其它行星轨道的异常
，因而接下来就是找寻所谓的「10号行星」(Planet X)，可是始终一无所获；当航海家2
号量测出海王星真正的 |
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s*****t
发帖数: 1994 | 30 The Outer Shells of Centaurus A
Credit: E. Peng and H. Ford (JHU), K. Freeman (ANU), R. White (STScI), CTIO, NOAO,
NSF
Explanation: What causes the surrounding shells in peculiar galaxy Cen A? Last month a
fascinating image of peculiar galaxy Centaurus A was released, processed to highlight a faint
blue arc indicating an ongoing collision with a smaller galaxy. Another interesting feature of
Cen A, however, is the surrounding system of shells, better visible here in |
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w****l
发帖数: 344 | 31 NGC 6240内的超大质量双黑洞
Credit: Optical: R.P.van der Marel & J.Gerssen (STScI), NASA;
X-ray: S.Komossa & G.Hasinger (MPE) et al., CXC, NASA
说明: 在图左哈勃望远镜拍摄的可见光照片里，可见距离我们4亿光年远的NGC 6240
，正处在一场星系碰撞的挣扎之中，合并中的星系展现出由恒星、云气和尘埃所组成
的扭曲潮汐尾，并引发暴发性的恒星诞生活动。天文学家用钱德拉X射线观测站，对
NGC 6240的明亮核心区进行了观测，检测到星际物质回旋掉进黑洞时所辐射出的特征
X射线辐射。天文学家因此推断出NGC 6240的核心有二个互相环绕的黑洞！右边这张
伪彩色特写照片里，X射线波段的数据明确的指出，这两颗黑洞相距约3000光年。爱
因斯坦的广义相对论预测，这对黑洞一定会盘旋着掉向对方，经过数亿年后，它们最
后会合并在一起，形成一颗质量更庞大的黑洞。在这两颗超大质量黑洞合并的最后时
刻，还会发出极强烈的引力波辐射。
原文来自： http://antwrp.gsfc.nasa. |
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发帖数: 344 | 32 自由漂浮的哈勃太空望远镜
Credit: STS-82 Crew, STScI, NASA
说明: 大部分望远镜都架设在地表上，为何要把一些望远镜放到太空中呢？在地表上
，你可以架设一个较重的望远镜，而且可以比较容易从事维修工作。然而，地面上的
望远镜不可避免地受到地球大气的影响。首先，地球大气遮挡了大部分的电磁波段，
只有可见光与部分电波到达地面,其它波段的探测设备就只好被放到大气外的太空中
，钱德拉X-光观测站就是其中的一个典型例子。其次，地球大气也会是使得星点变得
模糊不清,这主要是由于大气持续的抖动以及大气密度不停的变化所致。上图所示的
哈勃太空望远镜，是人类第一次将光学望远镜置于太空之中,直径2.4米，由于没有大
气的影响，可以获得比地面上大得多的望远镜尚无法达到的极高清晰度的影像。未来
，一个更大型的光学太空望远镜（已命名为韦伯望远镜）已列入计划之中。
原文来自： http://antwrp.gsfc.nasa.gov/apod/ap021124.html (linq编译) |
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发帖数: 344 | 33 年轻星系POX 186
Credit: Michael Corbin (CSC/STScI), William Vacca (MPE), NASA
说明: 不是很久以前，也不是那么遥远的地方，一个星系诞生了！这个由恒星、云气
和尘埃所组成的“宇宙岛”名为POX 186，位于室女座一处不太拥挤的天区里，距离
我们只有6800万光年而已。和我们的银河系相比，POX 186是个很小很小的星系。例
如，我们银河系横跨了十万光年的范围，含有2000亿颗恒星，而这个娇小星系的大小
只有900光年，含有大约1000万颗恒星。以宇宙的尺度来说，POX 186也很年轻。这张
哈勃太空望远镜拍摄的照片表明，这个扭曲星系的年龄可能只有一亿年，而且是两个
更小星系互撞的结果。分析表明象POX 186这种孤立的小型星系，可能是宇宙最后形
成的一批星系。
原文来自： http://antwrp.gsfc.nasa.gov/apod/ap030103.html (linq编译) |
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s*****t
发帖数: 1994 | 34 The Seasons of Saturn
Credit: R. G. French (Wellesley College) et al., Hubble Heritage Team (AURA / STScI /
NASA)
Explanation: Since Saturn's axis is tilted as it orbits the Sun, Saturn has seasons, like those
of planet Earth ... but Saturn's seasons last for over seven years. So what season is it on Saturn
now? Orbiting the equator, the tilt of the rings of Saturn provides quite a graphic seasonal
display. In fact, this month, Saturn's ring |
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s*****t
发帖数: 1994 | 35 NGC 7293: The Helix Nebula
Credit: NASA, NOAO, ESA, Hubble Helix Nebula Team, M. Meixner (STScI), & T. A.
Rector (NRAO)
Explanation: Will our Sun look like this one day? The Helix Nebula is the closest example of
a planetary nebula created at the end of the life of a Sun-like star. The outer gasses of the star
expelled into space appear from our vantage point as if we are looking down a helix. The
remnant central stellar core, destined to become a white dwarf star, gl |
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s*****t
发帖数: 1994 | 36 The Pencil Nebula Supernova Shockwave
Credit: Hubble Heritage Team (STScI/AURA), W. Blair (JHU) & D. Malin (David Malin
Images), NASA
Explanation: At 500,000 kilometers per hour, a supernova shockwave plows through
interstellar space. This shockwave is known as the Pencil Nebula, or NGC 2736, and is part of
the Vela supernova remnant, an expanding shell of a star that exploded about 11,000 years
ago. Initially the shockwave was moving at millions of kilometers per hou |
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s*****t
发帖数: 1994 | 37 Galaxies in the GOODS
Credit: NASA, ESA, GOODS Team, M. Giavalisco (STScI)
Explanation: This tantalizing view of galaxies scattered near and far is part of the Hubble
Space Telescope's contribution to the GOODS - the Great Observatories Origins Deep
Survey project. The GOODS' goal is to study galaxy formation and evolution over an
unprecedent wide range of cosmic distances, therefore spanning time from the present to the
early Universe. Joined by the Chandra X-ray Observatory and soon |
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s*****t
发帖数: 1994 | 38 NGC 1068 and the X-Ray Flashlight
Credit: X-ray: P. Ogle (UCSB) et al.; Optical: A.Capetti (INAF) et al.; CXO, STScI, NASA
Explanation: At night, tilting a flashlight up under your chin hides the glowing bulb from the
direct view of your friends. Light from the bulb still reflects from your face though, and can
give you a startling appearance. Spiral Galaxy NGC 1068 may be playing a similar trick on a
cosmic scale, hiding a central powerful source of x-rays -- likely a supermassive black hole -- |
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g****e
发帖数: 612 | 39 发信人: kuux (KUUX), 信区: Astronomy
标 题: [每日一图] 笔状星云的震波
发信站: BBS 水木清华站 (Tue Jul 15 19:54:03 2003)
Credit: Hubble Heritage Team (STScI/AURA), W. Blair (JHU) & D. Malin (David M
alin Images), NASA
说明: 一颗超新星爆炸的震波，以每小时50万公里的速度扫过整个星际空间,这便是造成著
名的笔状星云(NGC2736)的主因。这个星云是11,000年前一颗恒星爆炸之后所留下扩张壳状
的船帆座超新星爆炸遗骸的一部份。起初，震波是以每小时数百万公里的速度前进，然而
它在向外扩张过程中在周围气体的阻碍下，速度渐渐变慢。从上图这一照片中，我们可以
从左侧云气较少的情形推断出震波是由左向右移动的。这一张哈勃太空望远镜于2002年10
月间所拍摄的影像，跨度约1光年，它只是横跨约100光年的整个船帆座超新星爆炸遗骸的
一小部份。
原文来自： http://antwrp.gsfc.nasa.gov/apod/ap0306 |
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s*****t
发帖数: 1994 | 40 Big Mars from Hubble
Credit: J. Bell (Cornell U.), M. Wolff (SSI) et al., STScI, NASA
Explanation: At about 10 am Universal Time today, Mars and Earth will pass closer than in
nearly 60,000 years. Mars, noticeably red, will be the brightest object in the eastern sky just
after sunset. Tonight and through much of this week, many communities around the world
are running a public Mars Watch 2003 campaign, where local telescopes will zoom in on the
red planet. Pictured above is an image of |
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s*****t
发帖数: 1994 | 41 NGC 3370: A Sharper View
Credit: Hubble Heritage Team, A. Riess (STScI) NASA
Explanation: Similar in size and grand design to our own Milky Way, spiral galaxy NGC 3370 lies about 100
million light-years away toward the constellation Leo. Recorded here in exquisite detail by the Hubble Space
Telescope's Advanced Camera for Surveys, the big, beautiful face-on spiral does steal the show, but the sharp
image also reveals an impressive array of background galaxies in the field, str |
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s*****t
发帖数: 1994 | 42 Saturn: Lord of the Rings
Credit: Hubble Heritage Team, (AURA / STScI), R.G. French (Wellesley College), J. Cuzzi (NASA/Ames), L. Dones (SwRI), J. Lissauer (NASA/Ames)
Explanation: Born in 1564, Galileo used a telescope to explore the Solar System. In 1610, he became the first to be amazed by Saturn's rings, After nearly 400 years, Saturn's magnificent rings still offer one of the most stunning astronomical sights.
Uniquely bright compared to the rings of the other gas giants, Saturn's ring syst |
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s*****t
发帖数: 1994 | 43 M64: The Sleeping Beauty Galaxy
Credit: NASA and the Hubble Heritage Team (AURA/STScI), S. Smartt (IoA) & D. Richstone (U. Michigan) et al.
Explanation: The Sleeping Beauty galaxy may appear peaceful at first sight but it is actually tossing and turning. In an unexpected twist, recent observations have shown that the gas in the outer regions of this photogenic spiral is rotating in the
opposite direction from all of the stars! Collisions between gas in the inner and outer regions are creating ma |
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s*****t
发帖数: 1994 | 44 Persistent Saturnian Auroras
Credit: J. Clarke (Boston U.) & Z. Levay (STScI), ESA, NASA
Explanation: Are Saturn's auroras like Earth's? To help answer this question,
the Hubble Space Telescope and the Cassini spacecraft monitored Saturn's
South Pole simultaneously as Cassini closed in on the gas giant in
January 2004. Hubble snapped images in ultraviolet light, while Cassini
recorded radio emissions and monitored the solar wind. Like on Earth,
Saturn's auroras make total or partial rings around |
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s*****t
发帖数: 1994 | 45 Celebrating Hubble With NGC 6751
Credit: A. Hajian (USNO) et al., Hubble Heritage Team (STScI/ AURA), NASA
Explanation: Planetary nebulae can look simple, round, and planet-like in
small telescopes. But images from the orbiting Hubble Space Telescope
have become well known for showing these fluorescent gas shrouds of dying
Sun-like stars to possess a staggering variety of detailed symmetries
and shapes. This composite color Hubble image of NGC 6751 is a beautiful
example of a classic planetary n |
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s*****t
发帖数: 1994 | 46 The Cat's Eye Nebula from Hubble
Credit: NASA, ESA, HEIC, and The Hubble Heritage Team (STScI/AURA)
Explanation: Staring across interstellar space, the alluring Cat's Eye
nebula lies three thousand light-years from Earth. A classic planetary
nebula, the Cat's Eye (NGC 6543) represents a final, brief yet glorious
phase in the life of a sun-like star. This nebula's dying central star may
have produced the simple, outer pattern of dusty concentric shells by
shrugging off outer layers in a series of |
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f*r
发帖数: 3968 | 47 哈勃发现前所未有的激波
译：Jack
这张全新的哈勃照片向我们展示了正在形成行星状星云的原行星状星云。一垂死的恒
星（位于星云中央，隐藏在尘埃和气体之后）喷出大量的气体。一部分气体可以达到每小
时50-100万公里的高速。
蓝色的光源自超生激波与周围的物质相碰撞激发的氢和电离氮。这张图片第一次展示
了星云前所未有的复杂结构。
这张图片在四块不同的滤镜下由宽视场行星照相机2摄于2000年圣诞节。红色的光波
长为791nm（曝光900s），红色的为675nm（曝光900s），同时混合氢的光（656nm）和电
离氮的光（658nm）而成蓝光（曝光14700s）。
版权：ESA和Valentin Bujarrabal
天体类型：星云
天体：葫芦星云
设备：宽视场行星照相机2
译自 哈勃网站（http://oposite.stsci.edu）
▲ BACK |
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f*r
发帖数: 3968 | 48 NGC 2440（英文原文）
译：Jack
NGC 2440是另一个行星状星云，但它较NGC 2346有更加复杂的结构。NGC 2440的中央
星是已知最热的恒星之一，表面温度大约200，000摄氏度。其周围星云的复杂结构暗示天
文学家那儿存在源自中央星的周期性的喷射，有点类似NGC 2346。但是对于NGC 2440，每
次喷射的方向是不确定。同时，星云中充满着尘埃云，它们形成了从中央星向外辐射的暗
而长的条纹。另外，对于其中明亮的星云，是由于受中央星辐射的紫外线激发所至。NGC
2440被一个大而冷的星云所包围，它在一般的望远镜中是不可见，但在红外望远镜中却可
以被探测到。NGC 2440坐落在距地球4，000光年的船尾座内。
此照片由哈勃Heritage小组获得。
译自 哈勃网站（http://oposite.stsci.edu）
NGC 2440
（Chinese Version）
NGC 2440 is another planetary nebula ejected by a dying star, but it has |
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f*r
发帖数: 3968 | 49 “斯宾若格拉芙”星云（英文原文）
译：Jack
像一颗精心雕琢的宝石，行星状星云IC 418坐落在距地球2，000光年的天兔座内。这
张照片是哈勃太空望远镜的宽视场行星照相机2 近期拍摄的照片之一。
行星状星云是类似于太阳的恒星的演化归宿。IC 418中央的恒星在几千年前是一颗红
巨星，但之后它便抛射出它的外壳，形成了星云，现今它的直径已达到约0.1光年左右。
星云中心的恒星遗迹是红巨星炽热的核，从那儿发射出的紫外线激发周围的气体使之发射
出荧光。在以后的数千年中，这个星云会逐渐的解体，并且这颗恒星在其后的几十亿年中
会渐渐地冷却进而变成一颗白矮星。我们的太阳注定也会有同样的命运，但那时50亿年之
后的事了。
这是一张伪彩色的照片，使用宽视场行星照相机2 摄于1999年9月。红色代表离子氮
的发射（星云中最冷的气体），绿色代表氢的发射，蓝色代表离子氧的发射（星云中最热
的气体，最靠近中央的恒星）。在星云中出现的这些惊人的结构是全新的，它们的形成原
因还不为人所知。
译自 哈勃网站（http://oposite.stsci |
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发帖数: 3968 | 50 蝴蝶状的“派碧隆”（Papillon）星云揭示大质量恒星诞生之谜（英文原文）
译：Jack
NASA哈勃太空望远镜对位于N159中的恒星诞生区进行了观测，N159坐落在离我们170
，000光年远的伴星系——大麦哲伦星云中。其中，来自新生大质量恒星的星风奔流着穿
过大星云中的脊状和丝状结构。
译自 哈勃网站（http://oposite.stsci.edu）
A Butterfly-Shaped "Papillon" Nebula Yields Secrets of Massive Star Birth
（Chinese Version）
A NASA Hubble Space Telescope view of a turbulent cauldron of starbirth,
called N159, taking place 170,000 light-years away in our satellite galaxy,
the Large Magellanic Cloud (LMC). Torrential stellar w |
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