Astronomy

What is Astronomy? The science that studies

Kepler’s Laws Purpose: Explain the motion of the Earth and how that affects the creation of the lithosphere in the past and present

Formation of the Universe The Big Bang Theory States that the universe started as a small, hot dense mass then began to enlarge rapidly in a hot explosion, and it is still expanding today.

Kepler’s Laws Kepler: 1571 – 1630 1st law: The orbits of the planets are ellipses, with the Sun at one focus of the ellipse.

Kepler’s Laws A planet moves fastest when it is 2nd law: A planet moves fastest when it is closest to the sun and slowest when it is furthest from the sun.

Kepler’s Laws 3rd law: relationship between the distance of planets from the Sun, and their orbital periods.

Kepler’s Laws - Pictures First Law Second Law Third Law

Electromagnetic Radiation What does the Sun Emits? Electromagnetic Radiation Different waves of light based on wavelengths and frequency Arranged on the Electromagnetic Spectrum

Electromagnetic Spectrum Radio Waves—lowest energy Infrared waves Visible Light (ROY G BIV) UV Rays X-rays Gamma Rays—highest energy

Photosynthesis

Producing Energy Fusion Atoms combine together Used to produce energy https://www.youtube.com/watch?v=3rn339v_Q-w Producing Energy Fusion Atoms combine together Used to produce energy Helium & Hydrogen Fission Atoms split in two Used to produce energy What nuclear power plants do

Earth’s Motions Nutation Oscillatory (movement of the axis back and forth) of a rotating body Observed during precession Occurs about 18.6 years

Rotation The turning or spinning of a body on its axis Causes day and night The whole process takes 24 hours 14

Earth’s Motions Precession Tilt on a plane in an elliptical motion The North Star is not always the starting point of rotation

Tides and Gravity https://www.youtube.com/watch?v=5ohDG7RqQ9I

Tidal Currents Currents generated by tides Gravitational pull of the moon Strongest at high and low tides

What are Tides? What causes Tides? changes in elevation of the ocean surface What causes Tides? Gravitational forces of the moon and sun

Spring Tides Occur during the new and full moons All gravitational forces are added together Extreme high and low tides High tidal range

Neap Tides During the 1st and 3rd quarters of the Moon Gravitational forces are offset (__) Tidal range is the smallest value

Earth’s Motions Barycenter The center of mass where two or more celestial bodies orbit each other and balance each other out. Barycenter website with animation

Motion of a body along a path around some point in space. Revolution Motion of a body along a path around some point in space. Earth’s orbit is elliptical Earth’s distance from the sun varies 23

Seasons are caused by the tilting of the earth on its axis (23.5°) When the Earth is tilted towards the Sun – warmer seasons When the Earth is tilted away from the Sun – cooler seasons 24