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.

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

Day vs. Night Day & Night http://macmillanmh.com/science/2008/student/na/scienceinmotion/Common/SIM.html?Module=../Grade1/Chapter8-EarthMoves/

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.

Sunspot Movement by Rotation

cloud/storm movement by rotation

Movement of Earth through Space Revolution: movement of one object around another object (e.g., earth around sun). Earth’s Revolution Rate & Direction: year (365.25 days), counterclockwise Orbit: path of one object around another object; elliptical (oval) shaped http://www.classzone.com/books/earth_science/terc/content/visualizations/es0408/es0408page01.cfm?chapter_no=visualization

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

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 9:47 10:47 11:47

Do: What Causes Day and Night? Activity Sheet

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

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 http://macmillanmh.com/science/2008/student/na/scienceinmotion/Common/SIM.html?Module=../Grade4/Chapter8-EarthRevolvesAroundTheSun/

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

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

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.

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

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

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

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