1. AIM: Compare rotation to revolution. What causes day and night
AIM: Compare rotation to revolution. What causes day and night? OBJ: Given notes, video and activity sheet SWBAT explain the difference between rotation and revolution as well as what causes day and night with 70% accuracy DN: Distribute Astronomy Activity Sheet (w/ answer key); Astronomy Review Sheets (w/ answer key) ACT: Introduction to Rotation, Revolution (notes) Complete: What Causes Day and Night? Act. Sheet HW: Complete Earth in Space Activity Sheet; Astronomy Exam, Dec 19.

2. Movement of Earth through Space
Rotation: spinning of planet on its axis
Axis: imaginary line that passes through center of planet from north pole to south pole
Earth’s Rotation
Rate & Direction:
24 hrs, counterclockwise.
Rotation is the cause of day
and night. Movement:
west→east; sunrise: east,
sunset: west.
side facing sun: day
side facing away from sun:
night

3. Day vs. Night
Day & Night

4. Evidence of Rotation: star trails, sunspot movement, storm/cloud movement Polaris (North Star): a star that remains stationary in the night sky found directly above the north pole axis.

5. Sunspot Movement by Rotation

6. cloud/storm movement by rotation

7. Movement of Earth through Space
Revolution: movement of one object around another object (e.g., earth around sun).
Earth’s Revolution
Rate & Direction:
year ( days),
counterclockwise
Orbit: path of one
object around another
object; elliptical (oval) shaped

8. Evidence of Revolution: movement of different constellations seen in the night sky over the course of a year. Constellation: cluster of stars that form an imaginary mythological image

10. READING TIME ZONES If it is 2 AM in NY, what time is it in California
READING TIME ZONES If it is 2 AM in NY, what time is it in California? Boulder Colorado? Different time zones are the result of _________?
8: : : :47

11. Do: What Causes Day and Night? Activity Sheet

12. The Seasons
Why equator hot and poles cold? Weather: due to the uneven heating of the earth’s surface
Heat energy spread out
cooling effect
Indirect rays
Heat energy
concentrated
Direct rays
Indirect rays
Heat energy spread out
cooling effect

13. The Seasons Seasons: winter, spring, summer, fall (autumn);
changes in precipitation and temperature during the year.
Cause of the Seasons: tilt of the earth’s axis
Earth’s Tilt: 23.5° from vertical
0° tilt: spring, fall only
23.5° tilt: moderate temperatures
winter (cold), spring, summer (warm), fall
35°- 45° tilt: extreme temperatures
winter (v. cold), spring, summer (v. hot), fall
IMPORTANT:
north pole axis facing Sun: Summer
north pole axis facing away from Sun: Winter
Seasons NOT caused by change in Earth’s distance from the Sun
Earth farthest from Sun: summer (Northern Hemisphere)
Earth closest to Sun: winter (Northern Hemisphere)
Seasons

14. The Seasons
Solstice: shortest or longest day of the year Northern Hemisphere (NYS) Summer Solstice - June 21 N.P. axis faces towards Sun More hours daylight 40°N-45°N: 15 hrs light ________________ opposite ________________ Southern Hemisphere Winter Solstice – June 21 S.P. axis faces away Sun Less hours daylight 40°S-45°S: 9 hrs light

15. The Seasons Winter Solstice Dec 21 Summer Solstice June 21 Away Sun
Towards Sun
Cold
Warm
Warm
Cold

16. The Seasons Equinox: equal day & night (12 hours); 1st day spring/fall
March 21, Sept 23 – 12 hour
day everywhere on earth
N.P. axis not facing
towards or away
from Sun
At Equator:
12 hrs daylight
12 hrs darkness
year round;
Sun 90° directly overhead.

17. The Seasons Winter Solstice Dec 21 Summer Solstice June 21 Away Sun
Towards Sun
Cold
Warm
Warm
Cold

18. The Seasons Northern Hemisphere (NYS) Winter Solstice – Dec 21
N.P. axis faces away from Sun
Less hours daylight
40°N-45°N: 9 hrs light
_____________________ opposite ___________________
Southern Hemisphere
Summer Solstice – Dec 21 (yes, Christmas!!)
S.P. axis faces towards Sun
More hours daylight
40°S-45°S: 15 hrs light

19. The Seasons Winter Solstice Dec 21 Summer Solstice June 21 Away Sun
Towards Sun
Cold
Warm
Warm
Cold

20. The Seasons https://www.youtube.com/watch?v=F1nL_M1G1Xw 23.5°N 23.5°S
Summer
solstice
Winter
solstice