1. Unit D - Space Exploration
1.0 - Human Understanding of Both Earth and Space has Changed Over Time

2. 1.1 - Early Views About the Cosmos
- Early beliefs and studies of the night sky varied among numerous cultures
- Here is a brief list of different views held by ancient civilizations:

3. Culture
Belief
Mayan
- Celestial events were evidence of communication with gods
- The appearance of certain constellations or planets signaled the planting season
Mesopotamia
- Certain patterns of stars represented mythical creatures (they created the Zodiac)
- The position of stars and constellations were used to identify seasons for sowing or harvesting crops
Egyptian
- Certain gods were represented by constellations
- Temples and pyramids were built to represent the position of stars and constellations
Cheyenne
- Medicine wheels were built that acted as calendars that could be used to predict the rising of certain stars at particular times of the year

4. Tracking Cosmological Events
- A number of different events had important roles in most cultures around the world:
Solstices:
Equinoxes:

5. - A number of different monuments have been used to predict or represent cosmological events:
Stonehenge:
The Great Pyramids:

6. Models of Planetary Motion
Early astronomers attempted to explain and predict the motion of stars and planets by developing models
Geocentric Model:
First developed by:
Features:

7. Problems With the Geocentric Model
- The geocentric model had several problems with it:
1. Poor Ability to Predict Motion:
2. Overly Complicated:

8. The Heliocentric Model
First Developed by:
Features:
- Unfortunately, this model was not able to accurately predict the positions of celestial objects because of one simple misconception:

9. Kepler & Brahe
- About 100 years after Copernicus developed the heliocentric model, it was revised
Revision:
- This new model could accurately determine the future positions of planets and is the model we use today

10. 1.2 - Discovery Through Technology
- Changes in the technology available to astronomers allowed them to make more accurate measurements and have better data to develop more accurate models of the universe
Early Tools:
Quadrant
- a tool that allowed astronomers to determine the angle of elevation to an object in the sky
Astrolabe
- a tool that projected the night sky onto a 2-D surface, allowing astronomers to determine the position of planets and stars based on the date and time
Cross-staff
- a tool that allowed an astronomer to determine the position of a star relative to the position of the moon

11. The Telescope Optical Telescopes Radio Telescopes
- The first simple telescopes were developed in the late 16th century
- There are two main types of telescopes:
Optical Telescopes
Radio Telescopes

12. Time and Distance in Space
- Space is so huge that using normal measurements that we use here on Earth (such as meters or kilometers) becomes impractical
- We have a number of different measurements that are used in space:
Astronomical Units (AU)
- the average distance between the center of the Earth and the center of the sun (about 150,000,000 km)
- used to measure distances in a solar system
Light Years (ly)
- the distance that light travels in a year (about 9,000,000,000,000 km)
- used to measure interstellar distances
Parsec (pc)
- equal to about 3.26 ly
- official unit used by professional astronomers

13. How Long Ago Light Left the Object
- Because the distances in space are so large, it takes time for light to travel from objects to us
- As a result, we see objects as they appeared in the past
- Here are some examples:
Object in the Sky
How Long Ago Light Left the Object
Sun
8 min, 20 sec
Pluto
5 1/2 hours
Outer Limit of the Solar System
16 1/2 hours
Alpha Centauri
4 1/4 years
Galactic Center
27,000 years
Andromeda Galaxy
2,540,000 years
Galaxy GN-z11
13,400,000,000 years

14. 1.3 - The Distribution of Matter in Space
Stars:
- Stars can be classified based on their brightness and temperature in a Hertzprung-Russell diagram:

15. The Life of Stars
- All stars follow the same general "life cycle": 1.
- Within a nebula (a cloud of gas & dust), particles begin to collapse together under their mutual gravity and begin to heat up 2.
- As more mass collects, the temperature climbs and the mass begins to glow 3.
- When the temperature at the core reaches 10,000,000 K, hydrogen atoms fuse to form helium, and the ball of gas becomes a star 4.
- After a long period of time (millions to billions of years), the hydrogen is used up and heavier elements fuse. This leads to cooling and expansion of the star 5.
- Eventually, the temperature drops and fusion stops, and the star collapses under its own mass

16. Ordinary vs. Massive Stars
- What happens to a star when it collapses depends on its mass
1. Sun-like stars:
2. Massive stars:
3. Super-massive stars:

17. Star Groups - Star groups are divided into 2 main categories:
Constellations:
Asterisms:
- Large groups of stars collect in galaxies, which can be spiral, elliptical, or irregular in shape

18. 1.4 - Our Solar Neighbourhood
- Our solar system was created in a series of steps: 1. 2. 3.

20. Mercury
Venus

21. Earth
Mars

22. Jupiter
Saturn

23. Uranus
Neptune

24. Dwarf Planets, Asteroids & Comets
- Planets are not the only objects in the solar system
- There are a number of different objects that are not identified as planets:
1. Dwarf Planets
2. Asteroids
3. Comets

25. 1.5 - Describing the Position of Objects in Space
- To locate the position of an object in the sky you need to know two things:
How high it is above the horizon?
In which direction?
- When describing the position of objects in the sky, we give them coordinates that answer those questions:
Altitude:
Azimuth:

26. Ex: Determine the altitude and azimuth of the moon and the planet in 
the diagram below

27. 2.0 - Technological Developments and The Exploration of Space

28. 2.1 - Technologies for Space Transport
- Getting a spacecraft into orbit is no easy task
- To escape Earth's gravitational field in order to orbit the Earth, an object must be travelling at least 28,000 km/h
- The only way to do this was to design powerful rockets

29. Rocket Propulsion
- All rockets use Newton's 3rd Law of motion in order to operate:
Newton's 3rd Law:
- In a rocket, the mass of propellant gases being pushed with a large force downwards results in an upwards force that pushes the mass of the rocket upwards

30. Types of Propulsion Solid Fuel Rockets Liquid Fuel Rockets
- Currently, there are two main types of propulsion used in rockets used to launch payloads into space:
Solid Fuel Rockets
Liquid Fuel Rockets

31. A Brief History of Space Exploration
9th Century
- Chinese produce first gunpowder-powered rockets
1926
- Robert Goddard launches first liquid-fueled rocket
1945
- Germany produces the first rocket to leave the atmosphere (V2 - designed by Werner von Braun)
1957
- Soviet Union launches first satellite (Sputnik)
1961
- Yuri Gagarin (Soviet Union) becomes first human in space, and first human to orbit the Earth
1969
- Neil Armstrong (United States) becomes the first human to walk on the moon
1971
- Soviet Union launches first space station into Earth Orbit
1981
- United States launches the first space shuttle

32. The Parts of a Rocket - Rockets all consist of 3 basic parts: 1. 2. 3.

33. The Future of Space Transport
- Despite their power, chemical rockets are relatively inefficient
- Scientists are currently developing new technologies in order to travel to distant planets
1. Ion Drives
2. Solar Sails

34. Current & Future Spacecraft
- Currently, there are 3 main spacecraft types in use:
1. Manned capsules:
2. Space stations:
3. Space probes:

35. 2.2 - Technologies for Living in Space
- Space can be a very dangerous place to work and live
- The hazards of living in space include:
1. Environmental Hazards
2. Psychological Challenges to Confined Living
3. The Effects of Microgravity

36. The Space Suit
- To protect themselves from the environment of space, astronauts wear a space suit
- These suits work like a tiny self-contained spacecraft and have been developed over the last century

37. Living on a Space Station
- Long-term space missions, such as those to the International Space Station (ISS) require independence from Earth-based resources
- The ISS has several systems that allow it to run independently for months at a time:
1. Water Recycling
2. Oxygen Production
3. Electrical Power

38. Dealing With Microgravity
- Many jobs need to be done differently in the microgravity environment in space
1. Exercise:
2. Eating:
3. Sleeping:
4. Washing:

39. 2.3 - Using Space Technology to Meet Needs on Earth
- There are a number of products and technologies that we use everyday that were first developed or used for exploring space
- Thousands of products have been produced and sold that are based on NASA patents
- We also directly benefit from space research and technology

40. Satellites Artificial Satellite:
Artificial satellites typically orbit the Earth using one of two types of orbits:
1. Low-Earth Orbit
2. Geosynchronous Orbit

41. - Satellites can carry out a number of different roles:
1. Communication
2. Observation & Research
3. Navigation

42. The Global Positioning System
- The Global Positioning System (GPS) uses a system of 32 satellites that are used to fix a receiver's location on Earth's surface
- A GPS receiver determines your position in the following manner: 1.
- Satellites send very accurate time stamps to a receiver 2.
- These time stamps are compared to the receiver's internal clock 3.
- The difference in time between the satellite message and the internal clock is converted into a distance 4.
- These distances are then used to create spheres with each satellite at the center. With at least 3 spheres, there will be a tiny area of overlap - this is where the receiver is

43. Space-Age Materials & Systems
- Many devices originally planned for use in space have been put to practical use on Earth
- Some examples include:
1. Food:
2. Computers:
3. Digital Imaging:
4. Robotics:

44. 3.0 - Using Technology to Advance our Understanding of Space

45. 3.1 - Using Technology to see the Visible
- Since the 16th century, astronomers have taken advantage of the optical telescope to study stars and planets
- There are two main types of optical telescopes:
Type
Diagram
Description
Refracting
Reflecting

46. A Comparison of Optical Telescopes
- Each type of optical telescope has its own advantages and drawbacks:
Refracting Telescopes
Reflecting Telescopes
Advantages
Disadvantages

47. Segmented Mirror Telescopes
- Segmented mirror telescopes consist of a number of smaller hexagonal mirrors that are combined into a single large mirror surface

48. Space Telescopes
- There is one main disadvantage of Earth-based telescopes:
- Space-based telescopes eliminate this problem
- Two examples of space-based telescopes are the Hubble Space Telescope and the James Webb telescope that is due to launch in 2018

49. 3.2 - Using Technology to see Beyond the Visible
- Stars emit all portions of the electromagnetic spectrum, not just visible light
- We have ways of detecting the emissions from stars and other objects 
that are not producing visible light

50. Radio Telescopes
- Stars and other radio telescopes produce a lot of radio waves and microwaves
Radio Telescope:
There are three main advantages that radio telescopes have over optical telescopes: 1. 2. 3.

51. Interferometry
- One disadvantage of radio telescopes is that they have much poorer resolution than optical telescopes
One solution to this problem is to improve their resolution via interferometry
Interferometry:

52. 3.3 - Using Technology to Interpret Space
- Although telescopes can show us magnified images of stars, we can't use those images to determine what they are made of, how far away they are, or if they are approaching us or moving away
- We must rely on other technology and techniques to determine the answers to these questions

53. Measuring Distance
- We can measure distances to far away objects indirectly by using triangulation
Triangulation:
This requires a series of steps: 1. 2.

54. 3. 4. 5. 6.

55. Using Parallax Parallax:
- We can use the parallax for distant objects when measuring from Earth
- We simply take our measurements 6 months apart, so that we are on the opposite side of Earth's orbit, giving us a baseline of 2 AU to work with

56. Determining a Star's Composition
- We can determine the composition of a star by the spectrum that it emits
- The spectrum of a star will not be a complete spectrum - it will be missing portions
- These missing lines correspond to specific elements that are absorbing the light coming from the core of the star

57. Determining a Star's Direction and Speed of Motion
- You may have noticed that when a train passes you the sound coming from it changes in pitch
This is known as the Doppler effect
Doppler Effect:
- This phenomenon affects all waves, including light

58. Using the Doppler Effect to Measure Stellar Motion
- By observing changes in the position of the lines of elements in a spectrum, we can determine whether a star is moving towards us or away from us, and how fast it is moving
We call these changes blue shift and red shift
Blue Shift:
Red Shift:

59. 4.0 - Society and the Environment are Affected by Space Exploration

60. 4.1 - The Risks and Dangers of Space Exploration
- Space exploration is hazardous
- There have been numerous deaths and several near-misses where missions nearly ended in the deaths of their crew
Date
Mission
Outcome
1967
Apollo 1
3 astronauts die in fire during training
Soyuz 1
A cosmonaut died when the capsule parachute did not open
1971
Soyuz 11
3 cosmonauts die when their capsule depressurized in space
1986
Challenger
7 astronauts die as the Space Shuttle Challenger exploded shortly after launch
2003
Columbia
7 astronauts die as the Space Shuttle Columbia disintegrates on re-entry

61. There are numerous dangers in space travel:
Launch:
Re-entry:
Radiation:
Space Junk:

62. 4.2 - Canadian Contributions to Space Exploration
- Canadians have a long history of space exploration:
1839
The first magnetic observatory is built at the University of Toronto to study the aurora borealis
1962
Canada becomes the 3rd country to launch a satellite, Alouette 1
1969
Canada supplies the landing gear used on the first moon landing
1984
Marc Garneau becomes the first Canadian astronaut
1992
Roberta Bondar becomes the first Canadian female astronaut
1997
A Canadian-designed ramp is used on the Mars Pathfinder mission
2001
Chris Hadfield becomes the first Canadian to walk in space
2013
Chris Hadfield becomes the first Canadian to command the ISS

63. The Canadarm
- In 1981, when NASA's space shuttle became operational, the Canadian Space Agency supplied the Canadarm, a remote-controlled robotic arm that could be used to capture and launch satellites
- On board the ISS, an advanced version of the arm, called Canadarm 2 was installed
- This new arm had more mobility and finer control than the original arm

64. 4.3 – Issues Related to Space Exploration
- Space exploration is very expensive – it costs billions of dollars per year
- Many people suggest that the money would be better spent somewhere else (such as healthcare and education)
- Others argue that space exploration is necessary because it may help us to find improvements to our way of life here

65. Space and its Resources
- Space may have numerous resources to offer
- It is estimated that a single tonne asteroid could yield $350 billion worth of resources
- As well, if we found fuel and other resources needed for space travel in space, it would be much cheaper to travel to other planets
- For instance, rocks on the Moon could be used to obtain both hydrogen and oxygen (both of which are used for fuel)

66. Issues with Space Exploration and Exploitation
- There are several issues to consider with space exploration and the use of the materials found there:
Political:
Who owns space?
Who has the right to use those resources?
Who will determine how space is used?

67. Do we have a right to alter materials in space to meet our needs?
Ethical:
Is it right to spend money on space exploration when it is needed here on Earth?
Do we have a right to alter materials in space to meet our needs?
How can we ensure that resources will be used to benefit all of mankind instead of only one nation or group?

68. Who is responsible for protecting space environments from alteration?
Environmental:
Who is responsible for protecting space environments from alteration?
Who is responsible for cleaning up space junk, and who should pay for it?
- One possible solution is to treat space like Antarctica
- In 1959, the 12 countries that had bases on Antarctica agreed that:
“Antarctica shall continue forever to be used exclusively for peaceful purposes and shall not become the scene or object of international discord.”