1. Celestial Motion:
Looking Up

2. Constellation Polaris Star Planet
OUTCOME QUESTION(S):
S1-4-03:
Why were the position and motion of visible celestial objects important to past cultures?
How can you measure the location of objects in the sky?
Vocabulary & Concepts 
Constellation Polaris
Star Planet

3. The Science of Astronomy
Astronomy is the study of the Universe
Scientists who study Astronomy are known as Astronomers
Like most scientists, Astronomers aim to answer specific questions
What kind of questions do you think Astronomers are trying to answer?

4. The Science of Astronomy
Astronomers differ from most other scientists in one aspect…
Unlike most scientists, Astronomers cannot actually touch the objects they study because everything is so far away.
This makes Astronomy an observational science rather than an experimental science

5. Early History of Astronomy
Ancient people saw seven celestial bodies moving through the stars:
Sun
Moon
Mercury
Venus
Mars
Jupiter
Saturn

6. Early History of Astronomy
5 of these objects were considered to be “special stars” due to their movement patterns.
Ancient people called these special stars planets.
Only five planets can be seen without the naked eye…Which ones?
My Very Educated Master Just Showed Us Nine Planets

7. 1. Agricultural revolution: tracking stars became necessary to accurately mark the growing season.
Position allowed for creation of a calendar that had 365 days in a year.
There was both a spiritual and practical significance to tracking the celestial movements

8. Zodiac is Greek for “circle of animals”
2. Exploration and Trade: tracking stars used to navigate water for trade and conquest.
Stars and the Sun became the "landmarks" used.
Groups of stars are “constellations”
used to organize the sky
named for animals and gods
Zodiac is Greek for “circle of animals”

9. STONEHENGE

11. A star (Sun) and all the objects orbiting it
What is Up there?
Stars: very large collection of matter that emits an intense amount of energy (light and heat).
Planets: collection of matter that is generally spherical and revolves (orbits) around a star.
Our solar system:
A star (Sun) and all the objects orbiting it

12. Scientists estimate our solar system is 4.6 billions years old
Feature
Planet
Star
Location
Distance from Earth
Real size
Reason we see it
Surface temperature
Composition
Look
Motion over time
Far beyond the solar system
In the solar system
Fairly near
Very, very, very far
Smaller than most stars
Larger than planets
Reflects light
Emits light
Cold or very cool
Very hot
Rocks and/or gases
Gases
A constant light
Twinkles / flickers
Very slowly wanders through constellations
Move only as part of a constellation
Scientists estimate our solar system is 4.6 billions years old

13. CAN YOU ANSWER THESE QUESTIONS?
Why were the position and motion of visible celestial objects important to past cultures?
How can you measure the location of objects in the sky?
Vocabulary & Concepts 
Constellation Polaris
Star Planet

14. Ptolemy Copernicus Galileo
OUTCOME QUESTION(S):
S1-4-04:
How was the process of science important in showing the Sun is the centre of our solar system?
S1-4-05:
How does the position and motion of Earth produce day/night, the phases of the moon, and the seasons?
Vocabulary & Concepts 
Ptolemy Copernicus Galileo
Kepler Retrograde Geocentric Heliocentric Solstice Equinox

15. Celestial Motion:
History and Earth

16. Planet is Greek for “wanderer”
Ptolemy (100 AD)
Hypothesized “epicycles” to explain observations and knowledge of that time
Earth was centre of the universe - Geocentric
In good with the Church
Planet is Greek for “wanderer”
Observation:
Some planets seem to move backwards in orbits:
“Retrograde motion”

17. Called the “Founder of modern astronomy”
Copernicus (1473)
Produced mathematical evidence for a Sun-
centered system – heliocentric
Much simpler explanation for retrograde motion
Hypothesized Earth rotated on axis once daily and revolved around Sun once yearly
Not in good with Church
Called the “Founder of modern astronomy”

18. Galileo (1564)
Perfected the telescope (built a few years earlier)
First to state and use the scientific method
Discovered moons around Jupiter
1 Proof that not all objects traveled around Earth
Venus had phases (day/night) like Earth/moon
2 Proof that it traveled around the Sun
Not in good with the Church

19. Galileo’s drawings and scientific records of his observations

20. Galileo published his evidence confirming Copernicus’ mathematics, and was accused of heresy by the Church.
Would not recant his work as a mistake and spent entire life under house arrest
By the way, Pope John Paul II made a public apology and exonerated Galileo in 1992

21. Brahe’s goal was to prove Copernicus incorrect
Kepler (1571)
Worked as assistant for astronomer, Tycho Brahe
Brahe’s goal was to prove Copernicus incorrect
He received loads of money from the Church in hopes he could prove the Earth-centred view…he failed
Brahe built one of the best
observatories in the world
Measured positions of 777 stars and five planets that were known at that time

22. Kepler used Brahe’s data after his death to describe three laws of planetary motion:
1. Planets orbit the Sun in ellipses (not circles)
2. Planets move faster close to Sun, slower farther away
3. Planets farther away have a longer orbital period

23. What do we know today?

24. Earth rotates towards the East
The Earth rotates on its axis once a day.
At any time - half of Earth is in “day” and half in “night.”
Earth rotates towards the East
winter
summer
The Earth revolves around the Sun once a year.
At any time - half of Earth is in “winter” and half in “summer.”

25. Our axis is tilted at 23.5o (degrees)
This tilt and the curvature of the Earth is responsible for the variations in the Sun’s energy – and creates our seasons.

26. Summer Solstice (June 21)
Summer: not only more “direct” but also more hours of the Sun’s energy
Spring Equinox
(Mar 21)
12h and 12h
Winter
“indirect” energy
Winter Solstice
(Dec 21)
Shortest Day
Fall Equinox
(Sept 22)
12h and 12h
Summer Solstice (June 21)
Longest Day
Summer
“direct” energy

27. What do you notice?

28. That’s why there is a “dark side” of the Moon
Moon Rotation
Moon completes 1 rotation on its axis in the same time as it completes 1 revolution around the Earth (synchronous)
We always see the same side facing the Earth
That’s why there is a “dark side” of the Moon
Orbit is elliptical
Tilted 5°
Mean Distance: 384,400 km

29. Phases of the Moon
Shines only by reflected sunlight
Depends on fraction of sunlit half visible to us

31. What do people in the Southern hemisphere use?
The North Star – Polaris – is used for navigation.
Polaris is due north How high Polaris is in the sky (altitude) equals your latitude on the earth's surface.
What do people in the Southern hemisphere use?
LAND coordinates are called latitude and longitude.

32. This is Winnipeg

33. Measuring Angles in the Sky
Measuring Angles in the Sky

34. Astrolabe
Instrument used to calculate the position of objects in the sky with high accuracy
Perfected during Islamic Golden Age ( s)
Period of enormous growth in math, science and medicine

35. (measured with a compass)
Vertical (up/down) angle is called altitude:
Horizon – ground - 0°
Zenith – directly above - 90°
Horizontal (left/right) angle is called azimuth:
(measured with a compass)
North – azimuth of 0°
South – azimuth of 180°
A position in the SKY is given using altitude and azimuth as its “coordinates”
altitude
azimuth

36. CAN YOU ANSWER THESE QUESTIONS? S1-4-04:
How was the process of science important in showing the Sun is the centre of our solar system?
S1-4-05:
How does the position and motion of Earth produce day/night, the phases of the moon, and the seasons?
Vocabulary & Concepts 
Ptolemy Copernicus Galileo
Kepler Retrograde Geocentric Heliocentric Solstice Equinox