Astronomy 1ppt. by Robin D. Seamon
NOTE OUTLINE:
1.Historical Astronomers
2.Motion
3.Cycles:
• Seasons
• Moon phases
• tides
FAMOUS ASTRONOMERS
of the PAST
PTOLEMY
•Worked with sundials & trigonometry
•astronomer who accepted the common idea that the planets & Sun traveled around the Earth! (geocentric view)
WRONG!!!
COPERNICUS (1473-1543)
•Proposed that the Earth & other planets revolved around the sun (heliocentric view)
•People did NOT like this idea!RIGHT IDEA!!!
http://www.cyfronet.pl/~n1kokows/poszukiwania_en.html
http://students.ou.edu/G/Summer.D.Golden-1/coverpage.html
GALILEO GALILEI (1564-1642)
•Used the invention of the telescope & mathematics to look at the universe
•Observed The Milky Way, the moon, Jupiter’s moons & more
http://ml.shapiro.gs/?p=64http://www.wwnorton.com/college/english/nael/18century/topic_3/illustrations/imtelescope.htm
PBS: Telescopes
MOTION
http://utahscience.oremjr.alpine.k12.ut.us/Sciber06/6th/moon/html/rotate.htm
MOTION VOCABULARY:
•Axis: The tilt on which the earth spins (rotates)
•Latitude: lines running on a map or globe
•Longitude: lines running on a map or globe
•Rotation: spinning around from one point & back around
•Orbit: the path one body follows around another body
•Revolution: the movement of a body in orbit from one point back to that point; one complete trip
ADVANCE
LATITUDE:
Measured N & S of the Equator
LONGITUDE:
Measured E & W of the Prime Meridian
http://www.polaris.iastate.edu/NorthStar/Unit2/unit2_sub1.htm BACK
AXIS
http://pseudoastro.wordpress.com/2009/01/30/planet-x-and-2012-proof-earth-is-not-experiencing-a-pole-shift/
ROTATION
The earth makes one rotation on its axis every 24 hours. This makes day & night.
Earth satellite views: ppt. BACK
http://www.mhhe.com/physsci/astronomy/arny/instructor/graphics/ch04/0422.html
REVOLUTION
The earth travels one revolution around the sun in 365 Earth days.
BACK
Summer Solsticehttp://www.uwm.edu/~kahl/CoVis/Seasons/
JOHANNES KEPLER: (1600)
Mathematician & astronomer
•Kepler’s laws of motion:
•objects travel in an ellipse around another object
•objects move faster when closest to the sun and slower when farthest from the sun
•the more distant from the sun an object is, the longer it takes to orbit the sun
http://www.sciencekids.co.nz/sciencefacts/scientists/johanneskepler.html
http://kepler.nasa.gov/johannes/#anchor784359
SIR ISAAC NEWTON: (1643-1727) Mathematician & astronomer
NEWTON LINKBIOGRAPHY
•Newton’s 1st law of Motion: objects remain still or in motion until another force is applied to it (law of inertia)
•Newton’s 2nd law of Motion: acceleration happens when a force is acted on an object. The greater the mass of the object, the more force is needed to move it. (f=ma)
•Newton’s 3rd law of Motion: for every action, there is an equal and opposite reaction
•NEWTON LINK: explore the 3 laws
http://www.mrdowling.com/601-newton.html
VIDEO 1: planetary orbits are elliptical
p. 660-661
VIDEO 2: planetary rotation & revolution
Wandering Planets
LABp. 660-661
Why are there seasons on Earth?
•Equinox: when the sun is directly above the equator
•Solstice: when the sun is farthest N & S of the Equator
Summer Solstice
Winter Solstice
Autumn Equinox
Spring Equinox
http://www.metoffice.gov.uk/corporate/pressoffice/2006/pr20060317b.html
Seasons are dependent upon:
1.The Earth’s axis tilt
2.Where the Earth is on its solar revolution
Summer Solstice
HSW: VIDEO LINK(The Earth’s Seasons)
http://videos.howstuffworks.com/hsw/12886-spin-around-the-solar-system-the-earths-seasons-video.htm
Longer days in the Summer
Summer Solstice Equinoxes Winter Solstice
Shorter days in the Winter
Day & night are almost equal
Longest day
Shortest day
http://www.uwm.edu/~kahl/CoVis/Seasons/
Video: vernal equinox
Video: summer solstice
Video: winter solstice
Video: seasons, N & S poles
Why does the moon change?
•Moon: a smaller body circling a larger body in space
Luna: Earth’s moon
•Luna rotates on its axis in about 27.3 Earth days
•Luna revolves around the Earth in about 28 Earth days
(Therefore, we see the same FACE of the moon)
Google Earth images
Luna’s Phases:
VOCABULARY
• Waxing the appearance of the moon getting larger (more sunlight shining on it as nights go by)
• Waning the appearance of the moon getting smaller (less sunlight shining on it as nights go by
• Crescent
• Gibbous
Waxing crescent
Waning crescent
• Eclipse: the shadow of one celestial body falling on another body
1.Lunar eclipse
1.Solar eclipse
Earth’s shadow on moon during lunar eclipse
Shadow on moon during solar eclipse
VIDEO 2: lunar eclipse
VIDEO 3: solar eclipse
VIDEO 3: total eclipse of the sun
VIDEO 1: Eclipses
MOON & ECLIPSE PHASES
LABp. 658 &
659
TIDES
Moon’s gravity pulls on the Earth’s oceans, causing the level of water to rise or lower:
1.High tide
2. Low tide
http://www.fotonomy.com/CeterusParibus/photo/1ee2edd8/
1.Spring tides:
Largest daily range -during new & full moons; every 14 days
2. Neap tides:
Smaller daily range -during 1st & 3rd quarters of moon
(sun, Earth, moon align)
(sun & moon are at right angles to the Earth)
VIDEO: Tides
VIDEO: HSW The Beauty of Astronomy (2 min)
VIDEO: Seasons & Astronomy: Summer (20 min)
VIDEO: Seasons & Astronomy: Fall (20 min)
VIDEO: Seasons & Astronomy : Winter (20 min)
VIDEO: Seasons & Astronomy: Spring (20 min)
TELESCOPE LAB
p. 266