1. Introduction
2. Observations: initial knowledge about
the Solar System
3. Explaining the observations
4. Consequences for the Earth
5. The scientific method revisited
FORMATION OF EARTH AND
THE SOLAR SYSTEM
The Solar System- not to scale!
Sun Mercury
Venus Earth
Mars
Jupiter Saturn Uranus
Neptune
Pluto
The Solar System. Source: Christopherson, 2012, p. 41.
Pieces of the Allende meteorite. Source: Smithsonian Institution.
A chunk of Acasta gneiss, from northern Canada.
Source: Smithsonian Institution.
The Allende meteorite has been dated
radiometrically at about 4.6 billion years old.
The Acasta gneiss is the oldest rock yet found
on Earth, dated radiometrically at about 4.0
billion years old.
Thus, the Solar System is around 4.6 billion
years old, and the Earth formed somewhere
between 4.0 and 4.6 billion years ago.
The Solar System. Source: Christopherson, 2012, p. 41.
Planets all orbit the Sun in the same direction.
The inner Solar System. Source: Christopherson, 2012, p. 41.
Each planet rotates on its axis
in the same direction, except
for Venus and Uranus.
The Solar System- not to scale!
Rocky/terrestrial/inner planets:
Mercury, Venus, Earth, Mars
Gaseous/giant/outer planets:
Jupiter, Saturn, Uranus, Neptune
COMPOSITION OF ROCKY
vs. GASEOUS PLANETS
Rocky planets are ~90% iron, silicon, oxygen and
magnesium (Fe, Si, O and Mg)
Gaseous planets are mostly hydrogen, helium,
methane and ammonia (H, He, CH4, NH3)
SOLAR SYSTEM CHARACTERISTICS
1. Sun contains 99.9% of mass of solar system
2. Planets orbit the Sun in the same direction
3. Most planets rotate on their axes in the same
direction (Venus and Uranus are exceptions)
4. Orbits are elliptical, not circular, and lie roughly on
the same plane (the plane of the ecliptic)
5. Planets are roughly twice as far from the Sun as the
next planet in
6. Planets form two distinct groups- rocky vs. gaseous
Mercury The Moon
Mars
Meteor Crater, Arizona (Earth)
SO WHAT??
Consequences of Solar System’s
formation for the Earth
Consequences of Solar System’s
formation for the Earth
1. COMPOSITION
2. CHEMICAL DIFFERENTIATION
4. ORBITAL CHARACTERISTICS
Earth is >90% Fe, Si, O, Mg
Differences in crust vs. whole Earth (layers)
3. EARLY ATMOSPHERE
IRON
35%
IRON 6%
OXYGEN
30%
OXYGEN
46%
SILICON
15% SILICON
28%
MAGNESIUM
13%
MAGNESIUM
4%
ALUMINIUM 8%
NICKEL
2.4%
Consequences of Solar System’s
formation for the Earth
1. COMPOSITION
2. CHEMICAL DIFFERENTIATION
4. ORBITAL CHARACTERISTICS
Earth is >90% Fe, Si, O, Mg
Differences in crust vs. whole Earth (layers)
3. EARLY ATMOSPHERE Volcanic outgassing of CO2, CH4, etc.
Irregular- elliptical, tilt, wobble
Source: California and Carnegie Planet Search, www.exoplanets.org
Geographic location
• Latitude
• Longitude
Latitude. Source: Christopherson, 2012, p. 16.
Latitude. Source: Christopherson, 2012, p. 16.
Latitudinal zones. Source: Christopherson, 2012, p. 16.
Longitude. Source: Christopherson, 2012, p. 17.
Longitude. Source: Christopherson, 2012, p. 17.
Top Related