Summary of Videos and Relevant Text Chapters
Summaries from the Videos and Relevant Text Chapters
Summaries from the Videos and Relevant Text Chapters
Sun
Mars
Red color - from iron
Olympus Mons - largest in solar system, 15 miles high
Magnetic field protected it from solar winds, molten core could no longer support, loss of water on surface
1938 Orson Wells's War of the Worlds
1964 Mariner visited, only 1 pass - revealed craters
1971 Mariner 9 - multiple passes - complete mapping - Olympos Mons - about the size of Missouri
Mariner Valley - about size of US
1976 Viking mission landed on mars - at same time the orbiter photographed "the face"
Meteorite found in antarctica - thought it was part of asteroid, in early 1990 looked at it under electron microscope and some believed a worm was shown.
1996 - announcement that life had been found on Mars
Missions possible every 2 years due to alignment of planets
Many missions launched and planned for Mars: http://seds.org/~spider/mars/mars-l.html
Threats
The 1908 event in Siberia - explanations
Doomsday events discussed
1. Near Earth Encounter - comets from Oort cloud - almost a light year from the sun. Although no confirmed direct observations of the Oort
Cloud have been made, astronomers believe that it is the source of all long-period comets entering the inner Solar System.
Those that go into NEO - Near Earth Orbit - are most dangerous
2004 MN4, scheduled to return Friday 13, 2029: http://science.nasa.gov/headlines/y2005/13may_2004mn4.htm
2. Exploding Star - gamma ray bursts from - billions of light years away but carry a lot of energy
3. Death of our Sun
4. The Big Rip
Moon
A moon is a natural satellite rotating around a planet.
While moons vary in size, each moon is much smaller than its planet. Almost
140 moons are known in the Solar System.
Several moons are larger than the planet Pluto and two moons are larger than
the planet Mercury. There also are many small moons that may be asteroids
captured by their planets.
Only Mercury and Venus do not have any moons. By comparison, Earth has one
moon and Mars has two. Jupiter has the most of any planet. Saturn is second.
Earth's moon is one of the larger natural satellites with a diameter of
2,160 miles.
The largest moon is Ganymede with a diameter of 3,280 miles, even larger
than either of the planets Mercury and Pluto.
Why is the sky of our moon always black? no air molecules to scatter light
Theories for formation of our moon
1. The Fission Theory:
The Moon was once part of the Earth and somehow separated from the Earth early in the history of the Solar System. The present Pacific Ocean basin is the most popular site for the part of the Earth from which the Moon came
2. The Capture Theory:
The Moon was formed somewhere else, and was later captured by the gravitational field of the Earth.
3. The Condensation Theory:
The Moon and the Earth condensed together from the original nebula that formed the Solar System.
4. The Colliding Planetesimals Theory:
The interaction of earth-orbiting and Sun-orbiting planetesimals (very large chunks of rocks like asteroids) early in the history of the Solar System led to their breakup. The Moon condensed from this debris.
5. The Ejected Ring Theory:
A planetesimal the size of Mars struck the earth, ejecting large volumes of matter. A disk of orbiting material was formed, and this matter eventually condensed to form the Moon in orbit around the Earth.
Numbers
| Planet | Number of Moons |
| Earth | 1 |
| Mars | 2 |
| Mercury and Venus | 0 |
| Jupiter | 62 |
| Saturn | 33 |
| Uranus | 27 |
| Neptune | 13 |
| Pluto | 1 |
Earth
Jupiter
Huge: Could fit 1000 Earths inside Jupiter.
Largest planet in the Solar system
Failed star - not enough mass and pressure for fusion?
Jupiter has the most gravity in the Solar System
Some of Jupiter's moons
1. IO: some volcanos
2. Ganymede: largest moon in the Solar system
3. Europa: Ice Queen
Jupiter's magnetosphere - largest in the Solar system
Mercury
Venus