1 / 10

ASTRONOMY

ASTRONOMY. Chapter 31 Black Holes. Relativity. Einstein published his General Theory of Relativity in 1916 His Special Theory of Relativity, published in 1905, predicted that the speed of light did not change for any observer despite their motion.

kira
Download Presentation

ASTRONOMY

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ASTRONOMY Chapter 31 Black Holes

  2. Relativity • Einstein published his General Theory of Relativity in 1916 • His Special Theory of Relativity, published in 1905, predicted that the speed of light did not change for any observer despite their motion. • The General Theory brought gravity into the mix.

  3. Space-Time • General Theory says gravity warps space-time.

  4. What We Know

  5. What If… • What if more than 2 or 3 M˳ remain after a supernova? • The star collapses through the neutron degeneracy phase and keeps contracting • As the collapse continues, radiation leaving the surface becomes more red shifted. • The star collapses into a point of infinite density with no size called a singularity. • This is a black hole.

  6. The Photon Sphere

  7. The Photon Sphere • When the star shrinks, only light shinning within the exit cone will escape. • The more the star contracts, the smaller the exit cone becomes.

  8. Event Horizon • The radius of the collapsing star at the time that light can no longer escape is called the Schwarzschild radius and the sphere is called the event horizon. • The event horizon is 2/3 the radius of the photon sphere. • Neither of these is an actual surface.

  9. Event Horizon • When the star becomes smaller than its Schwarzschild radius, we can no longer see it. • We believe that it will contract to a zero radius. • The event horizon stays where it is.

  10. Other Black Holes • Mini black holes. • Supermassive black holes • Located at the center of galaxies • May contain thousands to millions of M˳

More Related