Astronomy Phys 181 GR Simulation

Quotes “Gravity as Newton and Einstein knew it does not exist. When the United States launched the first space probe it kept going off course. Well, it took them awhile to re-analyze all the evidence and what they came up with is that gravity does not exist in space. This is how I was able to detect what has since been called the "Quasars" or" Quasi- Stellar Sources". -Don Albert from Brain in a Box “I've never earned a penny in my life, not one single penny from any of the research I've ever done, no matter what I've discovered. And I've literally discovered somewhere between five and ten thousand new things, and they all seem to be totally worthless.”

Readings: ASTRONOMY TODAY Chapter 22 and 23 ReadingsReadings

General Solar Properties Neutron Star: Eta Carinae Neutron stars are the remanant of Type II (rebound) Supernova events.

Roughly the size of a major city. 300,000 times more massive than the earth. Composed primarily of neutrons. Escape velocity is c/2 Strong emission of radio waves.

Jocelyn Bell: 24 year old Cambridge grad student. Detection of periodic radio signals in the constellation Cygnus. Mysteriously regular at second intervals. In 1974, her advisor, Anthony Hewish, was awarded the Nobel Prize in Physics for the discovery of the PULSAR!

Hubble Image of the Crab Nebula Pulsar Rotates once every s !!!!

Black Holes

Space-Time is Curved

Albert Einstein General Theory of Relativity

All massive objects distort space and time in their vicinity. The distortion is the cause of Gravity Time Effects Gravitational Red Shifting Gravitational Lensing

Black hole properties: Light cannot escape Event horizon Mass (5 times the mass of the sun and greater) Angular momentum Charge (most are neutral) How can we detect them if they are black?

Gravitational Lensing Accretion Disk Emissions

Cygnus X-1 Deneb Vega Altair End

Phys 181 Astronomy

Readings: ASTRONOMY TODAY Ch 23.1, 23.2 Ch 24.1, 24.2, 24.5 Ch 26 ReadingsReadings

Quotes There was no "before" the beginning of our universe, because once upon a time there was no time. * John D. BarrowJohn D. Barrow I don't pretend to understand the Universe--it's a great deal bigger than I am. * Thomas CarlyleThomas Carlyle A universe that came from nothing in the big bang will disappear into nothing at the big crunch. Its glorious few zillion years of existence not even a memory. * Paul DaviesPaul Davies Anyone informed that the universe is expanding and contracting in pulsations of eighty billion years has a right to ask, "What's in it for me?" * Peter De Vries Nothing puzzles me more than the time and space; and yet nothing troubles me less. * Charles LambPeter De VriesCharles Lamb

Milky Way Galaxy

The Milky Way Galaxy: Vital Statistics Diameter - 100,000 light years Thickness (Nucleus) - 20,000 light years Thickness (Disc) - 2,000 light years Number of Stars - 200,000,000,000 Age - 15,000,000,000 years

The Halo

The Disk

The Core

Elliptical Galaxies 1/3 of all galaxies Giant Ellipticals are the size of our galaxy but are rare Dwarf Ellipticals are more common (6000 light yrs across) Riesen-E

Spiral Galaxies Largest fraction of galaxies Andromeda

Barred Spiral Galaxy NGC-1365

Irregulars Large Magellanic Cloud

Galaxies form groups or Clusters Coma Cluster

Olber’s Paradox

The universe is expanding!

Hubbles Law