Earth in Our Universe Big Bang Theory the

Earth in Our Universe

Big Bang Theory: the universe originated billions of years ago in an explosion from a single point of nearly infinite energy density. (red shift & cosmic background radiation evidence) https: //www. youtube. com/watch? v=koyoj. Pcpb. G 0 (2 min. video)

• Galaxies are a large-scale group of stars 100, 000 light years across (100 – 400 billion stars per galaxy). • Believed to be between 50 billion to 1 trillion galaxies in the universe. • 3 main types: Spiral, Elliptical, & Irregular. Light-year: distance light https: //www. youtube. com/watch? v=p. Oj. ZInwd 5 Ks (1 min. video) travels in one year at a rate of 186, 000 miles per second. (669, 600, 000 mph)

Nebular Theory: force of gravity caused gases and dust to contract with a densely packed core to form our solar system about 5 billion years ago. https: //www. youtube. com/watch? v=PL 3 YNQK 960 Y (3 minute video)

https: //www. youtube. com/watch? v=YU 6 X 3 SPZAJo (2 minute video)

• White dwarf stars are very dense: its mass is comparable to that of the Sun, while its volume is comparable to that of Earth. • Black dwarf stars are a white dwarf that has cooled down to the temperature of the cosmic microwave background, and so is invisible. • Neutron stars are city-size stellar objects with a mass about 1. 4 times that of the sun.