1.1 Scale and Organization

Question 1

What are atoms expressed in?

Answer 1

Nanometers; one billionth of a meter

Question 2

How big is a micrometer?

Answer 2

One-millionth of a meter
(size of cells, bacteria, and other small structures)

Question 3

What is an AU

Answer 3

• Astronomical Unit
• One AU is the average distance between the earth and sun’s centres: 149.6 million kilometers

Question 4

How much is a light year?

What is it typically used for?

Answer 4

• A unit of astronomical distance equal to the distance light travels in ONE YEAR in a vaccum
• The light year is used to express distances to stars and other celestial objects

Question 5

What is a parsec?

Answer 5

• Unit of distance larger than light years
• Equivalent to 3.26156 light years

Question 6

What is the Andromeda galaxy? How far away is it?

Answer 6

The Andromeda galaxy is the closest neighboring galaxy?

Question 7

What is the Proxima Centauri?

Answer 7

• Closest star to our sun: 1.301 pc

Question 8

What can we use for truly vast distances?

Answer 8

• Megaparsecs (MPS)
• equivalent to 1 million PC or 3.26 million ly

Question 9

How old is the universe?

Answer 9

• 13.77 billion years
• Based on microwave background radiation and the movement of galaxies following the big bang

Question 10

How old is the universe? - What is this estimate based on?

Answer 10

Microwave radiation and the movement of galaxies following the big bang

Question 11

What is “deep time”?

Answer 11

• “Deep” as in the time the Earth has existed, over 4.54 billion years

Question 12

How many units are there in the Geological Time Scale?

Answer 12

SEVERAL

Question 13

Which are the largest subdivisions of the GTS?

Answer 13

1. Eon
2. Era
3. Period
4. Epoch
5. Age

Question 14

How much does the precambrian represent?

Answer 14

• 87% of geological time
• NOTE: an informal division, not a main subdivision

Question 15

What is the Hadean Eon?

Answer 15

• A unit of time meant to represent the very earliest part of the Archean Eon
• NOTE: an informal division, not a main subdivision

Question 16

What is the upper part of the precambrian?

Answer 16

• The Proterozoic Eon
• Starts at 2.5Ga

Question 17

Which Eon is the most finely divided?

Answer 17

• The Phanerozoic
• 538.8Ma
• Because it’s younger than other Eons and more rock available for study

Question 18

How was each period in the Phanerozoic defined?

Answer 18

• When it was recognized that life became sufficiently different to warrant the erection of a new subdivision

Question 19

What do the differences between the eras in the Phanerozoic Eon represent?

Answer 19

• Sudden catastrophes in the biosphere called MASS EXTINCTION EVENTS

Question 20

FIGURE 9

Question 21

What is a system?

Answer 21

• A system is a set of interacting or interdependent components or elements that form a unified whole and exhibit properties and behaviours that emerge from the interactions among the components

Question 22

Earth’s 4 major systems:

Answer 22

• The biosphere
• The hydrosphere
• The geosphere
• The atmosphere