who discovered the first pulsar? jocelyn bell pulsars spin fast due to what physics concept?
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Who discovered the first pulsar?
Jocelyn Bell
Pulsars spin fast due to what physics
concept?
L = mvr v = L/(mr)
Conservation of Angular Momentum
Largest ~700Hz
Rapid Spin Rate
What is the average diameter of a pulsar?
Diameter = ~20km
How can pulsars help with nuclear physics?
Atomic Like Structures“atoms in the sky”
What does "PSC" stand for?
Pulsar Search Collaboratory
Which is correct for radio emission?
a) large wave length, high frequency, high energyb) small wave length, low frequency, low energyc) large wave length, low frequency, low energyd) small wave length, high frequency, low energy
c.) large wave length, low frequency, low energy
What does "DM" stand for?
Dispersion Measure
How high can pulsar space velocities be?
Over 1500 km/s
High Space Velocity
What household object can be compared to pulsars’ largest spin
rate?
Largest ~700Hz
Rapid Spin RateKitchen Blender
What is “noise”
Background radiation
What is the Dispersion Measure?
Dispersion Measure: A way measuring the number of electrons that a pulsar signal must pass through while traveling through space to the Earth. The units are parsecs per centimeter cubed.
Don’t forget that direction matters!
DM = Distance*Electron Density
What were pulsars first thought to be?
“Little Green Men” Theory
ALIENS
What two reasons do pulsars have a strong magnetic
field?
Strong Magnetic Field
extremely powerful magnetic fields of 108-1011 Tesla
-frozen magnetic field from the original star- rapid spin rate
How fast in hertz can a pulsar approximately
spin?
Largest ~700Hz
Rapid Spin Rate
Why do pulsars have a high space velocity?
Over 1500 km/s
High Space Velocity
Their supernova explosion was not perfectly symmetrical
What type of electromagnetic radiations
do pulsars emit?
radio, optical,
x-ray, gamma ray
What is ?
How can pulsars help further validate
Einstein's Relativity Theories?
Potentially directly
detecting gravitational
waves
Are pulsars broad band or narrow band
frequency?
Broad bandfrequency
What university were pulsars first discovered
at?
High space velocity is the vector sum of which two
vectors?
Over 1500 km/s
High Space Velocity
How can pulsars assist with future space
exploration?
Interstellar GPS System
Which telescope is the PSC data retrieved
from?
The Green Bank Telescope: The world’s largest fully steerable object in the world.
Who are the three sponsors of the PSC?
What is "RFI"
Man-made Radio
Frequency Interference
What type of electromagnetic radiation
does the PSC observe pulsars in?
RADIO
What type of space velocity stars are pulsars?
a) runaway starsb) halo starsc) hypervelocity stars
Over 1500 km/s
High Space Velocity
Hypervelocity Stars
Where is the Green Bank Telescope located?
Green Bank, West Virginia
How strong can pulsars’ magnetic fields be?
Strong Magnetic Field
extremely powerful magnetic fields of 108-1011 Tesla
-frozen magnetic field from the original star- rapid spin rate
How many solar masses is the Chandrasekhar Mass Limit?
Chandrasekhar Mass Limit1.4 solar masses =2.78474 × 1030 kilograms
How can pulsars assist in timing experiments?
Very Precise Spin Rates
What two officer positions are available in the Penn State
PSC?
What can DM help to measure?
Dispersion Measure: A way measuring the number of electrons that a pulsar signal must pass through while traveling through space to the Earth. The units are parsecs per centimeter cubed.
Don’t forget that direction matters!
DM = Distance*Electron Density
What year were pulsars discovered?
Jocelyn Bell
Name all five pulsar properties.
What do white dwarfs, neutron stars, and black holes all have
in common?
They are all at the end of a star’s life cycle.
What model is used to explain pulsars' pulse like signal?
Lighthouse Model
What university founded the PSC?
What are the three categories you can
categorize a PSC plot?
Pulsar
RFI
Noise
A pulsar is a super dense ______ star which emits dipole electromagnetic
radiation.
neutron
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