Planetary characteristics Review: Astronomy Main Ideas: Earth’s Motions Moon’s Cycle Satellites Orbits Planetary characteristics Star Classification Big Bang Theory
What determines the Earth’s time table? Rotation: spin on its axis; day; 24 hours : day/night Causes the Sun to appear to move 15 degrees per hour In NY State Sun highest in June lowest in Dec. Rises in East; Sets in West In Dec rises SE In June rises NE Sept/ March rise Due East
What is Earth’s other motion? Revolution: Orbit around the Sun; year 365.25 days Causes the seasons Equinox: 12 hours everywhere Sun above Equator March 21/ Sept 23 Solstice: Longer day/night Sun above Tropics Dec 21/ June 21
What does the Moon’s phases cause? Moon’s Phases: Caused by the Moon orbiting around the Earth. Always see the same side b/c the moon rotates and revolves at the same rate.
What else does the Moon’s Phases cause? Moon causes the tides Spring: higher highs; Sun & Moon are alligned Neap: Lower highs; Sun & Moon are at right angles
What are the two types of eclipses? Solar Eclipse: Moon is between the Earth and the Sun: New Moon phase Lunar Eclipse: Earth is between the Moon and the Sun Full Moon Phase
How do we determine a planet’s orbit? Orbit: planet revolving around Sun Ellipse: oval shape of orbit Eccentricity: shape of the ellipse E= Distance of foci length of major axis Answers between 0 and 1 One is a straight line Zero a perfect circle
How can we determine a planets characteristics? What is the only planets who’s day is longer than their year?
What is a star? Self luminating object. Energy emitted as elecromagnetic spectrum. Comes in different color and sizes. Sun is a main sequence star. Average in size and color
How can we classify stars? Stars are classified by either temperature, color or star class and by luminosity
What is a constellation? Constellation: Group of stars that make a character. Ancient people tell stories about them. Helped determine crops w/ planting. Big Dipper points to Polaris (North Star)
What is a galaxy? Galaxy: Billions of Stars Universe: Billions of galaxies
What is the Big Bang Theory? Theory of the start of the universe. Universe is still expanding. Proof: The Red Shift Expanding Contracting