NASA | Fermi Finds a Youthful Pulsar Among Ancient Stars
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In three years, NASA's Fermi has detected more than 100 gamma-ray pulsars, but something new has appeared. Among a type of pulsar with ages typically numbering a billion years or more, Fermi has found one that appears to have been born only millions of years ago.
A pulsar is a type of neutron star that emits electromagnetic energy at periodic intervals. A neutron star is the closest thing to a black hole that astronomers can observe directly, crushing half a million times more mass than Earth into a sphere no larger than a city. This matter is so compressed that even a teaspoonful weighs as much as Mount Everest.
Millisecond pulsars are thought to achieve such speeds because they are gravitationally bound in binary systems with normal stars. During part of their stellar lives, gas flows from the normal star to the pulsar. Over time, the impact of this falling gas gradually spins up the pulsar's rotation.
Be sure to go here (http://www.nasa.gov/externalflash/fermipulsar/) to see a new interactive map of all known pulsars.
This video is public domain and can be downloaded at: http://svs.gsfc.nasa.gov/goto?10858
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
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A pulsar is a type of neutron star that emits electromagnetic energy at periodic intervals. A neutron star is the closest thing to a black hole that astronomers can observe directly, crushing half a million times more mass than Earth into a sphere no larger than a city. This matter is so compressed that even a teaspoonful weighs as much as Mount Everest.
Millisecond pulsars are thought to achieve such speeds because they are gravitationally bound in binary systems with normal stars. During part of their stellar lives, gas flows from the normal star to the pulsar. Over time, the impact of this falling gas gradually spins up the pulsar's rotation.
Be sure to go here (http://www.nasa.gov/externalflash/fermipulsar/) to see a new interactive map of all known pulsars.
This video is public domain and can be downloaded at: http://svs.gsfc.nasa.gov/goto?10858
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.html
Or find NASA Goddard Space Flight Center on facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
