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Celestial Motion

Chapter 21, pages 597-606Chapter 22, pages 615-619

Lab starts this week—NS 017

Brief Review

• Sun is at the center of the solar system• Published by Copernicus

– Supported by Galileo’s telescopic observations of Jupiter and Venus

• Kepler determined orbits are ellipses• Newton determined orbits created by

interaction of inertia and gravity

Constellations

• Star groups• 88 recognized• Stars names by brightness in them

Orion

• Hunter• White Tiger• Southern Sky

• http://lithops.as.arizona.edu/~jill/EPO/Posters/Orion/protoplanets.html

Star names in Orion

• http://borghetto.astrofili.org/costellazioni/costellazioni.htm • http://www.windows.ucar.edu/the_universe/images/starmaps/map_orion.jpg

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• http://www.windows.ucar.edu/cgi-bin/tour_def/the_universe/images/starmaps/map_canis_major_jpg_image.html • http://www.windows.ucar.edu/cgi-bin/tour_def/the_universe/Arcturus.html

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Earth Movement

• Rotation on axis• Revolution (orbit) around Sun

What is a ‘day’?

• Mean Solar Day

What is a ‘day’?

• Sidereal Day

What is a ‘day’?

• Mean Solar Day—24 hours• Sidereal Day—23 hours, 56 minutes

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Animation link -- http://www.astro.virginia.edu/class/oconnell/astr121/im/lunation-anim.gif

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Moon’s Motion

• Rotates on axis once each 27 1/3 days• Same side always faces Earth• No atmosphere—extreme temperature

variation: 127o to -173o C

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Moon

• 3475 km diameter

• Density ~ Earth’s mantle

http://www.astrosurf.com/cidadao/moon_99_03_01.jpg

Meteor Impact

Compression Wave Ejecta Rim

Euler Crater Lunar Features

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Maria Formation Flood Basalt

Lunar ExplorationFootprint in

lunar regolith

Moon formation

http://www.psi.edu/hartmann/pic-cat/

Impact of asteroid

http://www.psi.edu/hartmann/pic-cat/

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Ejecta from impact

http://www.psi.edu/hartmann/pic-cat/

Coalesced to form Moon

http://www.psi.edu/hartmann/pic-cat/

Moon was initially hot

http://www.psi.edu/hartmann/pic-cat/

Moon by Apollo

17 CrewRight part of

photo is ‘dark side’that cannot be seen from Earth

http://spacekids.hq.nasa.gov/osskids/animate/moon.html

Rayed Crater

http://cnr2.kent.edu/~manley/copernicus_crater_area.jpg

Lab Starts this Week

• Room NS 017• Down the south stairs• Do not miss class the first week• Buy your lab manual and read the first lab• Do the prelab questions, because your lab

instructor may want you to hand them in