Lecture 1 Flashcards
(27 cards)
What are the things needed for Intelligent life?
1) A star that is just the right size, about 0.75 - 1.5 as large as earths sun
2) A planet that is about the size of earth
3) The planet must be a terrestrial planet
4) Has to have lots of liquid
5) The planet must be the right distance from the sun
6) The planet must maintain a relatively circular orbit
7) The planet must rotate on its axis relatively frequently
What are the 3 layers of the Earth
1) Hydrosphere
2) Atmosphere
3) Lithosphere
The hydrosphere is the
worlds oceans
The Atmosphere is the
very thin layer that holds gases to the earths surface via gravity
The Lithosphere is the
Earths rocks
The biosphere is the
area of the Hydrosphere, Atmosphere and lithosphere that contains life/living organisms
Is very thin layer
What gases make up the suns atmosphere
89% Hydrogen
11% Helium
What gases make up Venus atmosphere
96% carbon dioxide
4% nitrogen
What gases make up Earths atmosphere
78% Nitrogen
21% oxygen
0.9% Argon
What gases make up Mars atmosphere
95% Carbon dioxide
3% Nitrogen
What gases make up Jupitar atmosphere
90% Hydrogen
10% Helium
What gases make up Saturns atmosphere
96% hydrogen
4% Helium
What gases make up Uranus and neptones atmosphere
85% Hydrogen
15% Helium
The Big Bang happened how many years ago
13.9 Billion
The Sun formed how many years ago
5 Billion
The Earth formed how many years ago
4.6 Billion
Photosynthesis and the oldest Fossils are dated back how many years ago
3.7 Billion
Vertebrates in Fossil Records date back how many years ago
500 Million
What happened when the Ozone formed?
IT allowed for life on land possible as the Ozone blocks the Suns UV rays
When did the Ozone form?
400 million years ago
Mammals and reptiles date back how long ago
350 Million years
When did the dinosaurs become extinct? but what survived
65 million years ago except the birds survived
The Early homo-ancestors date back to
250 thousand years ago
Homosapiens date back to
50 thousand years ago
