module 1

Question 1

what is our current understanding of the formation of the earth

Answer 1

-A dense cloud of gas and dust approx 4.5-4.6 million years ago and the dust collapsed
- this formed a solar nebula and at the center was hydrogen and helium which combined and released energy, and created the sun and 99% of avalible matter
- matter aggregated and formed things.
EVIDENCE: meterorites, meteroite craters, shooting stars, sample of solar system material

Question 2

How do we get info about planetary age and composition

Answer 2

• isotopic dating
  -radioactive isotopes decay (protons and neutrons leave randomly).
  -they have a proportional decay rate and a half life
• produces a unique parent and daughter isotope which can be used to determine planetary age
• tungson isopte used to date formation of earth and stars

Question 3

what conditions are assumed for carbon dating

Answer 3

a)That the rock is not eroded or have lost material over time.
b)That the rock has not been contaminated while eroding

Question 4

how and when did earth form?

Answer 4

-earth melts and minerals mixed
- iron and nickle begin to settle towards the center
- differentiated earth with light rock crust, intermediate density mantle, liquid outer core, nickle and iron core

Question 5

how and when did the moon form

Answer 5

giant impact theory
- proto planet hits earth. ejection from this impact formed the moon
- created from proto planet and earth

Question 6

how do other planets in the solar system differ from earth

Answer 6

terrestrial and non-terrestrial planets

Question 7

terrestrial planets

Answer 7

• mercury, venus, earth and mars
• developed as hot rocky metals
  -all have undergone differentiation
• earth is THE ONLY ONE with tectonic plates which accounts for the structure of earth (mountains)
  -theory that other terrestial planets has tectonic plates because of their structure (ie venus has mountains)

Question 8

non terrestrial plantes

Answer 8

-formed from gases
- outer planets
- Jupiter Saturn, uranus, and neptune

Question 9

scientific evidence of planet formation

Answer 9

• metereorites
  -sample of solar system material
  -shooting stars

Question 10

meteroites

Answer 10

• may contain chondrules which are small particles solidified from molten droplets
• rich in iron and silion
  -types:iron, stony-iron, chronrites, carbonaceous chondrites

Question 11

periodic cycles in earth’s orbit

Answer 11

-changes in eccentrity
-axial precession
-changes in obliquity

Question 12

earths layers

Answer 12

• crust
  -upper mantle
  -lower mantle
  -outer core
  -inner core