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Дата индексирования: Mon Oct 1 21:18:35 2012
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Поисковые слова: crab nebula

<b style="color:black;background-color:#ffff66">Crab</b> <b style="color:black;background-color:#66ffff">Nebula</b>

NGC 1952

Crab Nebula

M 1

RA 5:35; Dec 22:01 (Taurus)
Type: supernova remnant
Distance: 6000 ly
In 1758, Charles Messier found this nebula while hunting for comets. When he noticed that, unlike a comet, it didn't move, he decided to create his now famous catalog (from his point of view a catalog of things that shouldn't be mistaken for comets).
The supernova explosion that created the Crab was seen on about July 4 1054 AD. It was recorded by Chinese astronomers and perhaps others.
The gas is expanding so fast that we can see actual changes by comparing new photographs with those taken early in this century. Notice how much more compact M 1 is than the Vela SNR which is 10 times older.
At the center of the Crab is a pulsar, the neutron star that remains from the original star. Neutron stars are fantastic objects -- just a few kilometers in diameter but with the mass of the Sun and very rapidly rotating (the Crab pulsar rotates 30 times per second, some pulsars ten times faster).

NOAO 32k jpg

UA 40k gif
(caption)

SEDS 196k gif
(caption)

HST 567k mpg
(caption)

SEDS 32k gif

SEDS 6k gif

SEDS 60k gif
UO 60k gif

SEDS 22k gif

Hale 49k gif

UO 70k gif
(caption)

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1999 Jan 12