Earth and Moon
Jan 03, 2016
The Surface of Earth• Geologically Active with a surface that is
constantly changing– Weathering and erosion– Plate tectonics
Atmosphere of Earth• Oxygen rich
• Blocks out most of the sun’s damaging rays
• The atmosphere deflects millions of tiny and not so tiny meteors every day that otherwise would have hit the earth and us.
Characteristics of our Moon• Gravity is only one-sixth as strong as Earth’s
• Temperatures can range from 100oC to -170oC
• No air or liquid water
Apollo Moon Missions
• 1963-1972• Apollo 11, 12, 14, 16, 17 landed humans on the
surface of the moon• The six missions that landed on the moon returned
a wealth of data and 400 kg of lunar samples.• Experiments included soil mechanics, meteoroids,
seismic, heat flow, lunar ranging, magnetic fields, and solar wind experiments.
The Sun
• Average size yellow star
• 110 times the diameter of the Earth
• Approximely 4.6 billion years old
The Surface of the Sun• The photosphere
• 5,000-8,000 oC
• The sunlight that reaches Earth comes from the photosphere
Features of the SunSunspots
Areas of gas on the sun that are cooler than thegases around them
Sunspot cycle of 10-11 years
Features of the SunSolar Flares
An explosion ofHydrogen gas from The sun’s surfaceThat occurs when Loops in sunspot Regions connect
Increases solar wind Causes magnetic storms
Historical Contributions in Earth-moon-sun
Aristotle (384-322 BC)
-Greek philosopher and scientist
-Believed in an earth-centered universe
-Thought the heavens moved naturally and endlessly in a complex circular motion
Earth-Centered Models
Ptolemy (100-170 AD)• Astronomer and mathematician
• Believed the earth was stationary and was the center of the universe
• Tried to solve the problem of retrograde movement of Mars
marsmovie.gif
Sun-Centered Models
• Copernicus (1473-1543)– Believed in a sun-centered
universe (Heliocentric)– Earth orbits the sun in a circular motion– Did not publish his theory until his
death because of the Catholic Church