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what's up for november

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the crab nebula hello and welcome i'm

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jane houston jones at nasa's jet

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propulsion laboratory in pasadena

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california

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2009 is the international year of

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astronomy

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and this month's special viewing target

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is the crab nebula

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the only supernova remnant that's easy

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to see from a modest telescope

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in 1758 charles messier was scanning the

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skies for comet halley

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he noticed a whitish light shaped like

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the flame of a candle in the

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constellation taurus

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he soon noticed it wasn't moving against

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the background stars

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so it couldn't be the comet m1

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became the first entry in his catalog of

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110

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this object was discovered in 1731 by

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english amateur astronomer john beavis

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and sketched by irish astronomer william

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parsons

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the third earl of ross in 1844

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through his big 36-inch reflector

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telescope

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his sketch resembled a crab and the name

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crab nebula stuck

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the history of this object goes back

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even further

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a guest star was visible in the summer

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sky of 1054.

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ancient astronomers in both the old and

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new worlds documented a bright new star

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in the daytime sky it was a supernova in

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the constellation taurus

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and was visible with the unaided eye for

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nearly two years

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in the 1940s the 100-inch hooker

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telescope at mount wilson was used to

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compute back

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to when the crab nebula first began to

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expand

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it began near the time of the supernova

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of 1054.

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at the center of the nebula is a rapidly

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spinning neutron star

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or pulsar which emits pulses of

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radiation 30 times a second

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in 1967 british astronomy graduate

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student jocelyn bell discovered this

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first pulsar

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three of nasa's great observatories show

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that the super dense neutron star

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is energizing the expanding nebula

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the chandra x-ray image traces the most

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energetic particles

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the white dot in the center is the

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pulsar

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spitzer's infrared image traces the

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cloud of electrons trapped within the

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star's magnetic field

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and the hubble telescope's image

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invisible light is one of the largest

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images taken by hubble's wide field and

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planetary camera 2.

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the crab nebula is faint but it can be

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seen with binoculars if your sky

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conditions are really good

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aim your binoculars at the red giant

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star aldebaran in taurus

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draw a straight line out to the

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southernmost of the bull's horns

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and the crab nebula is right next to

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that star

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you'll see a fuzzy patch shaped like the

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it's difficult but not impossible to see

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the faint neutron star within the crab

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nebula

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if you can see two stars the fainter of

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the two is the crab pulsar

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it's one of the few historically

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observed supernovae

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in our milky way galaxy so go out and

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try to see it

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on november 17th if you can get away

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from city lights you'll have a great

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view of the annual leonid meteor shower

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after midnight local time you should see

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lots of shooting stars

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you can learn all about nasa's missions

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at www.nasa.gov