1. Right Now…
There are only 13 days before final exams, meaning you have 13 days to make a significant impact on your grade.
Find your new seat. This is where you will stay until I see some major improvements.

2. Bell Ringer – answer based on previous knowledge
The Earth rotates on its axis once every (24 hours/365 days), making one (day/year). The Earth orbits around the Sun once every (24 hours/365 days), making one (day/year).

3. Astronomy and the earth

4. Tools of Astronomy
Astronomy – study of objects beyond Earth’s atmosphere
The most useful tool for observing space is electromagnetic radiation that comes to Earth from distant objects

5. Tools of Astronomy
Electromagnetic (EM) radiation – form of energy that travels as a wave
Includes radio waves, microwaves, infrared, visible light, ultraviolet (UV), x-rays, and gamma rays

6. Tools of Astronomy
Earth’s atmosphere blocks most EM waves, so objects must be sent into space to observe these types of radiation
Examples: satellites and space stations

7. Tools of Astronomy
Telescopes – devices that observe radiation on Earth
Most are used in rural areas, at high elevations
Keck Observatory,
Hawaii

8. Photos from Hubble Telescope
Can be used with other pieces of equipment such as cameras
Photos from Hubble Telescope

9. Tools of Astronomy Reflecting Telescopes – use mirrors to focus light
Refracting Telescopes – use lenses to focus light
Reflecting Telescopes – use mirrors to focus light
Most commonly-used type of telescope

10. Check for Understanding
How are satellites and telescopes similar?
What’s the difference between a satellite and a telescope?
Which telescope uses a mirror?
Which telescope uses a lens?
both are used to study outer space
satellite – in space; telescope – on Earth
reflecting
refracting

11. Units of Measurement Commonly Used in Astronomy:
Astronomical Unit (AU) = the average distance from the Sun to the Earth

12. Units of Measurement Commonly Used in Astronomy:
Light year = the distance that light travels in one year (nearly 6 trillion miles!)
Example: It takes over 4 years for light to travel from Earth to our next-closest star, Proxima Centauri

13. Earth’s Rotation
The Earth rotates (spins) on its axis once every day, about every 24 hours
Facing the Sun = day
Facing away from the Sun = night
At the equator, Earth is spinning at a rate of 1040 mph

14. Earth’s Rotation
Earth’s rotation is the reason why the Sun appears to rise in the east and set in the west, as well as the Moon and stars at night

15. Earth’s Revolution
The Earth and other planets revolve (orbit) around the Sun counterclockwise in the same plane
Ecliptic – the plane in which planets orbit around the Sun

16. Earth’s Revolution
The Earth completes one revolution around the Sun once every year, about 365 days

17. Earth’s Revolution
Earth’s axis is tilted 23.5o in relation to the ecliptic
This tilt causes Earth’s seasons (summer when the Earth is tilted _______ the Sun, winter when it is tilted _____)
towards
away

18. Earth’s Revolution
The Northern and Southern Hemispheres have opposite seasons
Example: December is the beginning of winter in the Northern Hemisphere and the beginning of summer in the Southern Hemisphere

19. Check for Understanding
How often does Earth revolve?
How often does Earth rotate?
What causes seasons?

20. Solstices and Equinoxes (in Northern Hemisphere specifically)
Summer Solstice -- June 21 (1st day of summer)
Northern Hemisphere tilted toward the Sun
Sun directly over the Tropic of Cancer (23.5° N)
Maximum amount of daylight hours (longest day)
Constant daylight within the Arctic Circle (66.6°N)

21. Constant Daylight

22. Solstices and Equinoxes
Winter Solstice -- December 21 (1st day of winter)
Northern Hemisphere tilted away from the Sun
Sun directly over the Tropic of Capricorn (23.5° S)
Minimum amount of daylight hours (shortest day)
Constant darkness within Arctic Circle (66.6°N)

23. Solstices and Equinoxes
Occurs in this month
1st day of this season
North Hemi is pointed
Longest __ of the year
Shortest __ of the year
North Pole:
Winter Solstice
Dec
Winter
Daylight
Summer Solstice
June
Summer
Darkness
Away
Night
Day
Towards
Day
Night

24. Solstices and Equinoxes
Equinox -- equal-length days and nights (equinox means “equal nights”)
Sun is directly over the equator
Halfway between the summer and winter solstices
March and September (1st days of spring and fall)

25. Solstices and Equinoxes
Occurs in this month
1st day of this season
Days are
(>, <, =) to Nights
Vernal
Spring
Autumnal
Fall
March =
September =

26. Precession and Nutation
Precession – the wobbling of the Earth on its axis, completing a circle every 26,000 years

27. Precession and Nutation
Non-science example: spinning top

28. Precession and Nutation
Nutation – Earth’s wavy path as it wobbles on its axis
Mainly caused by the effects of the Moon’s orbit around the Earth

29. Today Complete Vocabulary Assignment – INDEPENDENTLY, IN YOUR OWN SEAT
If you have headphones, you may listen to music
Turn into basket when you are done
I will let you look at your tests from Friday at the end of class

30. Good Summary for Today:

32. Vocabulary Complete Vocabulary Sheet
When done, get 5 ½ sheets of paper and staple them together (Station 1)
Choose 5 of the words on your vocab and make a book about them.
Vocab Term (nice and big)
A QUALITY picture illustrating the term
A short definition IN YOUR OWN WORDS describing the term
Staple together when done

33. Rhyme Time Columbus sailed the ocean blue
Complete the sentence: “In 14 hundred 92, _____________________________”
Columbus sailed the ocean blue
Our brains have the ability to better retain information when it is set to songs or rhymes.
Create a couplet (2 rhyming lines) for EACH of the following topics from today’s notes: rotation, revolution, solstices, equinoxes
These couplets should have important (testable) information in them.
You DO NOT have to rhyme the key words. Example: “Equinoxes are in the spring and fall, they bring equal day and night for one and all.”