Chapter 13-Neutron Stars and Black Holes
Characteristics of neutron stars
-extremely small and very massive -made of neutrons packed together -20 km across w/ a mass greater than the sun -incredibly dense -solid objects -gravity is extremely powerful -rotates extremely fast -strong magnetic fields
Einsteins 3 Key Premises of Relativity
1-speed of light is same for everyone 2-nothing travels faster than light 3-all things (including light) are affected by gravity
What are Pulsars?
Radio radiation in the form of rapid pulses -each has its own characteristic pulse shape and period
Do neutrons Stars have Pulsars?
Yes. Hot spots on a neutron star continually emit radiation in a narrow beam, particles at the hot spots emits beams of light that rotate (like a lighthouse) and we see pulses if the beam sweeps past earth.
What is a Black Hole?
concentrations of mass where gravity is so strong (not even light) can escape
How do we find a rotation period of a neutron star?
figure out the pulse period
So why can't light escape a black hole?
for light to escape, there has to be a minimum speed--so when the speed needed to escape is greater exceeds the speed of light, it can't escape
What is Einsteins theory on gravity?
gravity is not a result of force but from a curvature of space and time. Masses curve the space around them and the curve leads to gravity, the more mass the more curve there is
What Happens after a Type 2 Supernovae explosion?
iron core of a massive star collapses, the central part of the core rebounds, making a shock wave that destroys the rest of the star.
Why do Neutron Stars rotate extremely fast?
it is a result of the "law of conservation of angular momentum" that states any rotating body must spin faster as it shrinks and the core of the parent star most certainly already had a rotation.
What is Schwarzschild Radius?
radius where the escape speed is equal to the speed of light
What's left over after a Type 2 supernovae explosion?
ultra compressed ball of neutrons called a Neutron Star