Map
of Dark Matter 黑暗物質地圖 (18/7/2003)
這個世界上原來有很多物質是存在著，但是看不見的，稱為黑暗物質。不要看輕這些看不見的物質，它比正常看得到的物質多出5倍，果真，它們非常神秘。天文學家根據一些觀測資料和模型計算，把一個叫CL0024+1654的星系團的質量分佈圖製作了出來。當中紅色的正常的物質(星系)，而藍色的是黑暗物質。
Caption::
This is a mass map of galaxy cluster CL0024+1654 derived from an extensive
Hubble Space Telescope campaign. The colour image is made from two images:
a dark-matter map (the blue part of the image) and a 'luminous-matter'
map determined from the galaxies in the cluster (the red part of the image).
They were constructed by feeding Hubble and ground-based observations
into advanced mathematical mass-mapping models. The map shows that dark
matter is present where the galaxies clump together. The mass of the galaxies
is shown in red, the mass of the dark matter in blue. The dark matter
behaves like a 'glue', holding the cluster together. The dark-matter distribution
in the cluster is not spherical. A secondary concentration of dark-matter
mass is shown in blue to the upper right of the main concentration.
Credit::
European Space Agency, NASA and Jean-Paul Kneib (Observatoire Midi-Pyrenees,
France/Caltech, USA)
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Clouds
雲 (17/7/2003)
又是，沒有什麼特別好說，這些雲很美，就是這樣。
Caption::
Again, nothing special to say. The clouds are very beautiful, that's all.
Credit::
Kai Chiang
|
NGC
6520 & B86 (16/7/2003)
平時看上去銀河，看到的是一團光，或是覺得它是一塊雲，但原來銀河其實是由很多又很多的星組合而成，肉眼分辨不到，但用大望遠鏡就清楚看到一點點的星(好像圖中一樣)。這圖裏面有2個天體，一個是疏散星團
NGC6520，即左面那個，而右面那個是一個黑暗星雲B86。
Caption::
The majority of old stars in our Galaxy, as in most others, are yellowish
in colour. This is because the hotter, bright blue stars have relatively
short but spectacular lives. We see these old stars in vast numbers as
the brightest patches of the Milky Way and a powerful telescope like the
AAT is needed to see them as individuals. Superimposed on this distant
background is a small cluster of young blue stars, NGC 6520. In the same
region and possibly associated with the cluster is a dark cloud, Barnard
86. The cluster and cloud are probably associated and the dust is visible
only because it blocks out light from the myriads of stars beyond.
Credit::
David Malin, Anglo-Australian Observatory
|
Rising
Mars 火星出 (15/7/2003)
有否留意到最近晚上，在天上有一顆很亮又很紅的星？如果有留意下消息，都可能聽過火星會在八月大衝，即跟地球非常接近，而且是幾萬年來最近的一次，不過其實我無計過，我唔知係咪，人咁講我咁講，不過有趣的是每人講的數字都不同
:D，雖然如此，但今次的火星很接近是無所置疑的。所以有機會記得去看看火星，圖中在石中紅色的就是火星。
Caption::
Mars is heading for its closest encounter with Earth in over 50,000 years.
Although Mars and Earth continue in their normal orbits around the Sun,
about every two years Earth and Mars are on the same part of their orbit
as seen from the Sun. When this happens again in late August, Mars will
be almost as near to the Sun as it ever gets, while simultaneously Earth
will be almost as far from the Sun as it ever gets. This means that now
is a great time to launch your space probe to Mars. Alternatively, these
next few months are a great time to see a bright red Mars from your backyard.
Mars is so close that global features should be visible even through a
small telescope. Look for Mars to rise about 11 pm and to remain the brightest
red object in the sky until sunrise. Mars will rise increasingly earlier
until its closest approach in late August. Mars was captured above rising
through the Arch Rock in Valley of Fire State Park, Nevada, USA.
Credit::
Wally Pacholka
|
Flock
of Geese 雁群 (14/7/2003)
沒什麼特別要介紹，只是想給大家看看這張相，一群雁在飛翔的景況。這輻相於新麥西哥拍攝的。
Caption::
That's nothing special with this pic, just want to let you to have a look
at it only. This picture shows a flock of geese flying over New Mexico.
Credit::
John Warden
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