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Why Is Mars Red Mastering Astronomy Homework

Physics 104: Introduction to the Sky & Solar System....Spring 2002 - it's been a while since I've taught this one

Instructor: Kirk Korista
Office: 2226 Everett Tower
Office phone: 387-4971
Physics Department Office: 1120 Everett Tower
Physics Department phone: 387-4940
Western Michigan University home page is here

This course's textbook: The Essential Cosmic Perspective (4th Edition) by Bennett, Donahue, Schneider, & Voit. To gain access to Mastering Astronomy, our textbook's wonderful on-line tutorial, go to the above webpages and click on our book. If you haven't registered with the on-line tutorial, then do so using the access code number printed in Mastering Astronomy packet, included with your textbook if you bought it new. First time users will be asked to register and to set a login name and password. If you bought your textbook used, and you want access to this optional yet valuable on-line tutorial, you'll have to purchase an access code on-line (click on "buy now") for $27. We have received tremendous positive feedback from students who have taken advantage of our book's on-line tutorial. If you bought your textbook new, you've already paid for the service, so why not check it out? If not, you might consider paying the extra little bit or working with a buddy who has access to the site.
  • The course syllabus is here (to be relinked next time I teach this course).
  • The expectations of a teacher of introductory astronomy.
  • Here are some tips for succeeding in an introductory astronomy course.
  • Here is an amusing essay on how to fail an introductory astronomy course, written by my Ph.D. thesis advisor.
  • The Lecture: a Powerful Tool for Intellectual Liberation

Some quotable quotes about science

Science is built up with facts, as a house is with stones. But a collection of facts is no more a science than a heap of stones is a house.-Jules Henri Poincare is not a database of unconnected factoids but a set of methods designed to describe and interpret phenomena, past or present, aimed at building a testable body of knowledge open to rejection or confirmation.-Michael Shermer (Scientific American, September 2002)

Like all sciences, astronomy advances most rapidly when confronted with exceptions to its theories... - from Modern Astrophysics (Bradley Carroll & Dale Ostlie)

Science is a way of trying not fooling yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman (Physics Nobel Laureate)
Poets say science takes away from the beauty of the stars - mere globs of gas atoms. Nothing is 'mere'. I too can see the stars on a desert night, and feel them. But do I see less or more? The vastness of the heavens stretches my imagination - stuck on this carousel my little eye can catch one-million-year-old light. A vast pattern - of which I am a part... What is the pattern or the meaning or the why? It does not do harm to the mystery to know a little more about it. For far more marvelous is the truth than any artists of the past imagined it. Why do the poets of the present not speak of it? What men are poets who can speak of Jupiter if he were a man, but if he is an immense spinning sphere of methane and ammonia must be silent? - Richard Feynman (1918-1988), Physics Nobel Laureate, from The Feynman Lectures on Physics, 1963.

  • A wonderful, yet brief,essay describing what science is and how it works
  • Do you know the difference between science and pseudoscience? If you don't, read this.
  • Do "unlikely" events confuse you? Then read this, and this.
  • What's wrong with teaching "intelligent design" in the science classroom? and where's the science in ID?
  • An example of how ignorance and lack of critical thinking skills can it!
  • What's that, you say? Astrology is rubbish?
  • Andwhy should anybody care about Physics? How does it affect the life of the average person?

  • Class Announcements (to be updated next time I teach this course)
    • Unit 1An Introduction to Our Place in the Cosmos and the Cycling Sky Reading Assignment:
    • Unit 2History & Tools of Astronomy Reading Assignment:
    • Unit 3The Solar System Reading Assignment:
    All exams/quizzes: Bring a couple of #2 pencils and an eraser.

    Your Chance to view through a telescope
  • Free Public Telescopic Observing Sessions of the night sky for 2005 at the Kalamazoo Nature Center (usually beginning after twilight, if skies are clear; here is a map), sponsored by the Kalamazoo Astronomical Society (KAS). Here is the scheduled list of events.

  • For all observing sessions: dress appropriately; events are outdoors, and there are no restroom facilities. The KAS will supply the telescopes; all you need is a pair of eyes. However, if you have binoculars or your own telescope, feel free to bring it out. KAS members will also be happy to help you use your telescope.

    A few selected web sites relevant to astronomy
    A link to the webpage of other introductory astronomy course I teach, Physics 1060
    My personal page on the issue of light pollution
    The Kalamazoo Astronomical Society (local amateur astronomy club) page is here
    Astronomy Picture of the Day
    The musings of a a local amateur astronomer
    All the latest and greatest from the Hubble Space Telescope
    The new sciences of astrobiology and astrochemistry - finding life's building blocks in the cosmos.
    See the Earth having a bad day.
    An editorial from the Kalamazoo Gazette, March 12, 1998, illustrating a common misunderstanding of how science works (and a poor understanding of cosmology), and here is my response to that editorial, Viewpoint March 25, 1998.

    The Universal Inquirer...inquiring minds want to know...The following set of links contain information on topics related to but beyond the content of this course. Nevertheless, some of you may find them interesting.
    • Links to discussions of science, pseudoscience, and issues regarding science and faith...

    Some really cool JAVA animation demos in astronomy are here, here , & here
    A web-site with neat time-lapse photography of lunar phases, eclipses, Jupiter's moons, etc. .
    Another really nice set of computer simulations illustrating the workings of the sky: from the celestial sphere to the phases of the Moon.

    Hey! How did this happen? Shuttle STS-98 casts a shadow on the full Moon?
    Hey! How did this happen? A square sun at sunset?
    Another setting sun...with a rare blue and green flash
    Hexogonal ice crystals acting as prisms - and putting on a show in the sky
    This event nearly always generates strong emotions within me, though I couldn't say why....
    At an altitude of 384 km, the International Space Station here and here

    And now, some pretty pictures of the heavens...

    Unit 1: An Introduction to Our Place in the Cosmos and the Cycling Sky

    This is a nice illustration showing the planets and largest moons within our solar system to scale by size.
    Sizing up the Earth and Sun - the following are a series of comparitive scale models of the Earth and Sun relative to the other planets and other stars of known size: 1, 2, 3, 4, 5

  • Earth's Rotation
    • The rotating sky: the Canadian-French-Hawaii 3.9-meter dome on Mauna Kea, and sky near the North Celestial Pole (1.5 hour time exposure photo).
    • A short gif movie of the rotating sky near the north celestial pole (courtesy of Antonio Cidadao)
    • A nifty html animation of how the celestial sphere (and so the motions of object in the sky due to Earth's rotation) changes.
  • The relationship between  distance, physical size and angular size is beautifully illustrated in these side-by-side images of the Sun and Moon at their furthest (aphelion and apogee) from and closest (perihelion and perigee) distances to the Earth. All photographs (courtesy Earth Science Picture of the Day) were taken as the Sun and Moon reached their highest point in the sky on the particular date. The slightly reddish hue of the perigee Moon on July 2, 2004 is due to its low altitude in the sky and so its light must pass through a greater column of Earth's atmosphere whose molecules and particulates scatter shorter wavelengths of sun light more than longer ones - the same effect as a red or orange sun near sunrise or sunset.

  • A nice animation demonstrating the reasons for the changing seasons on Earth.
  • The Ecliptic
  • Jupiter, Venus, & Saturn in the pre-dawn sky of 26 July, 2001
  • A line up of all 5 visible planets in the dusk sky of 23 April, 2002 (artificial cross hairs and lines were drawn into this photo to indicate the planets' and constellations' locations)
  • A really cool line up of all 5 visible planets with Stonehenge in the foreground, from 4 May, 2002.
  • Phases of the Moon
    • A rising Full Moon, as observed by space shuttle astronauts
    • What's strange about this image of the Full Moon?
    • A nearly 1st quarter Moon, as observed by humans on Earth
    • A super image of the Moon along the day-night terminator during 3rd quarter
    • Earthshine during a waning crescent phase.
    • ``Love & War by Moonlight'' - The waxing crescent Moon in the western dusk sky of 14 May, 2002 along with bright Venus and dim Mars. Note the Earthshine on the portion of the Moon unilluminated by the Sun.
    • A superb image of a waning crescent Moon, in the early morning eastern sky of 4 September 2002. Note also the portion of the Moon lit up by Earthshine (sunlight reflected off the Earth and then onto the surface of the Moon). Also visible in the lower right corner of this photo are Jupiter, its 4 Galileo moons, and the Beehive star cluster.
    • Here is a gif movie of time-lapsed photography of the Moon going through its phases (courtesy of  Antonio Cidadao)
    • a JAVA script demo of the phases of the Moon
  • Eclipses
    • a JAVA script demo showing how partial, total, annular solar eclipses occur
    • a gif movie of a partial solar eclipse
    • See the stages of a total solar eclipse (February 1998)
    • The Sun as it appears at mid-solar eclipse (February 1998)
    • An annular eclipse of the Sun (January 1992)
    • The last eclipse of the previous millenium, a partial eclipse on 25 December, 2000
    • The first eclipse of the new millenium, a total eclipse on 21 June, 2001; here is a photocomposite of 22 exposures of the same eclipse. This is another spectacular composite image of a solar eclipse (on 29 March 2006).
    • The Moon's shadow cast upon the Earth during the August 1999 total solar eclipse
    • Using the leaves of a tree as a pinhole camera to image a solar eclipse (note the crescent-shaped images on the ground).
    • a gif animation showing the Moon passing into Earth's shadow for a lunar eclipse
    • A 4-hr exposure photo of the full moon, a moon trail, during the total lunar eclipse (January 2000)
    • The Moon as it appeared going into, within, and coming out of a total lunar eclipse (January 2000), and six months later (July 2000)
    • A multi-image animation of the Moon occulting (eclipsing) Saturn (Sept. 1997), and a series of snapshots of the same (February 20, 2002)
    • a set of internet links about solar and lunar eclipses

    Unit 2: The History and Tools of Astronomy

  • A movie illustrating the formerly mysterious retrograde motion: Jupiter & Saturn in the constellation Taurus (2000 June - 2001 May)
  • A series of photographs of Mars taken during 2003 demonstrating retrograde motion. Mars loomed largest during Earth's closest approach in late August.
  • a JAVA script demo demonstrating the same motion
  • a JAVA script demo demonstrating Kepler's Laws of Planetary Motion
  • JAVA script demo for parallax
  • Here is an animated series of photographs showing the phases of Venus
  • The Bay of Fundy, Nova Scotia, has the world's most extreme ocean tides, up to 16 meters in variation of ocean depth. This amounts 14 cubic km (14 billion metric tonnes) of ocean rushing in and out every 6 hours and 12 minutes - enough to tilt the Nova Scotia countryside downward during high tide! Here are pictures of low and high tides. These are the result of the Moon's gravitational pull varying across Earth's diameter (the near side of the Earth is closer to the Moon's center than the Earth's center, which is in turn closer than the far side of the Earth).  These differential gravitational forces are called tidal forces. The Sun also exerts tidal forces on the Earth, but with about 1/2 the effect of the Moon.

  • Telescopes
    • Overhead view of Yerkes Observatory in Williams Bay, WI, and the 40-inch refractor here and here
    • The Cerro Tololo Interamerican Observatory (Chile) 4-meter dome and beautiful night sky
    • The Very Large Telescope Array (Chile) and one of its 8.2-meter telescopes
    • A cartoon of the twin 10-meter (segmented mirror) Keck I & II Observatories, atop Mauna Kea, Hawaii, and a photograph of these two observatories plus the 8-meter Subaru - note the ocean of clouds lying below. Another cutaway view of the twin Keck 10-meter telescopes.
    • The new MMT telescope (6.5-meter) in southern Arizona
    • The Very Large Array Radio Observatory in New Mexico
    • Three photos of the Hubble Space Telescope (HST): in the Shuttle bay for repairs, in action, and why astronauts cannot suffer from vertigo - the HST within the Shuttle bay for repairs, 600 km above the western coast of Australia
    • A movie of speckle images of the bright star Betelgeuse, 30 msec per frame, demonstrating atmospheric "twinkling"; the effects of atmospheric turbulence is also quite evident here in a movie of Mars taken by a small telescope in August 2003.
    • A movie from the Keck Telescope showing the Galactic Center before and after the adaptive optics is turned on, removing the effects of atmospheric "twinkling"
  • Light
  • JAVA script demos for the Doppler Effect, 1/(distance)2 dilution of light, & blackbody radiation (light emitted by dense gas, liquid or solids)
  • Unit 3: The Solar System
  • Our star: the Sun on the outside
    • as it appears at visual wavelengths: the photosphere, and here
    • an extreme closeup of the Sun's photosphere: sunspot and granules
    • an extreme closeup of the Sun's photosphere: a movie of a sunspot complex and granules in motion
    • sunspots in motion, showing the Sun's rotation; here is another movie
    • the Sun's upper atmosphere observable during eclipse
    • observing the chromosphere in the light of hydrogen-alpha, 656.3 nm here and here
    • chromospheric spicules, in the light of hydrogen-alpha
    • the transition zone, in the light of ionized helium, 30.4 nm
    • the corona, in visible light (during eclipse)
    • the corona in light of 8x,9x ionized iron (17.1 nm), 11x ionized iron (19.5 nm), plus 14x ionized iron (28.4 nm)
    • coronal loops in extreme UV light, also here
    • the corona in continuous X-ray light
    • an mpeg movie showing images of our Sun across the electromagnetic spectrum, from the photosphere up into the corona. These images were taken at approximately the same time. Notice the brightest active regions in the Sun's hot upper atmosphere correspond to the darker/cooler sunspots that lie beneath in its photosphere.
    • a cartoon showing the major outer structures
    • large solar prominance in the light of ionized helium, 30.4 nm here
    • a solar flare (eruptive prominence) in the light of ionized helium, 30.4 nm
    • an mpeg movie of our Sun's active corona (November 2000)
    • a cartoon of the solar wind interacting with Earth's magnetic field
    • some pictures of aurorae: 1, 2, 3, 4, and here in SW Michigan (October 28, 2000)
    • a photo of an aurora taken by astronauts on-board the International Space Station; note the thin blue veil that is the Earth's lower atmosphere (troposphere and stratosphere), and that aurorae occur Earth's tenuous upper atmosphere. The white circular feature on Earth's surface is a snow-filled 212 million year old impact crater in northern Canada.
    • links to pages on aurorae (and predictions thereof) and other solar-terrestrial interactions
  • The birth of stars and planets in other solar systems
    • The Orion Nebula, nearest stellar nursery, at visual wavelengths, and even more spectacularly, here and here. The Orion star forming complex is just 0.5-1 million years old.
    • The Orion Nebula's Trapezium, visual vs. infrared, as observed by the Hubble Space Telescope. Note the large numbers of stars that come into view at infrared wavelengths - infrared light is not as easily blocked by dusty gas as is visible light. The dimmest points of light in the infrared image are ``Brown Dwarfs'', not massive enough to become stars.
    • Two image galleries (1, 2) of solar systems forming around new stars in the Orion Nebula, and a cartoon. The dark, dusty disks may form planets.
    • The Eagle Nebula, Hubble Space Telescope visual wavelengths image
    • Young stars with cool dusty gas disks around them: 1, 2, 3, 4, 5
    • Artist's conception of the first-ever observed (11/99) transit of a star by its orbiting planet: HD209458
    • A tiny interplanetary dust grain, just 10 microns across: building block of planets
    • Simplistic computer simulations showing the stages of star/planet formation (really just an animation)
  • The terrestrial planets
    • A comparison of the Solar System's largest moons, Mercury and Pluto (actual images, to scale)
    • Earth: Apollo 17 image, Galileo spacecraft's view, Galileo spacecraft views Earth & Moon together, Spacecraft Clemetine's view, a view of Earth, Moon and Hubble Space Telescope from the Space Shuttle Discovery, and from 3.6 million km out the Earth & Moon together from the Mars Odyssey explorer, and the first image of Earth (and its Moon) from another planet - taken by the Mars Global Surveyor (May 2003).
    • Go here to read the awestruck reactions of astronauts gazing upon their home planet...
    • Space shuttle astronaut's suborbital view of a sunrise; see herea blue ocean and Earth's delicate atmosphere.
    • Space shuttle astronaut's views of a hurricane, and thunderstorms over the Brazillian rainforest.
    • Mercury: crescent
    • Venus, a cloudy world: gibbous phase, image from Magellan spacecraft; a UV image from the Hubble Space Telescope
    • Mars: Hubble Space Telescope images 1, 2, 3, and this pair taken during the historic nearest passage to Earth in 60,000 years
    • Mars: Pathfinder ground image ground image and a large, color panorama
    • Mars: the global dust storm of 2001; before and after from the Hubble Space Telescope
    • Mars: its larger of two moons, Phobos as imaged by the Mars Global Surveyor, and again as imaged by the Mars Express.
    • Sedimentary rocks on Mars?
    • Recent liquid water on Mars?
    • A large north polar dust storm on Mars
    • the so-called ``face of Mars'' at 2 meter resolution
    • the NASA Mars exploration home page
    • High (sub-meter) resolution images from the Mars Recon Orbiter
  • The jovian planets
    • Jupiter: Hubble Space Telescope images 1, 2
    • Jupiter: Voyager 1 approach
    • A movie of Jupiter's: great redspot and atmosphere, by the Cassini explorer
    • More images of Jupiter from Cassini: Jupiter & Io, Jupiter & Ganymede
    • Jupiter's Galilean moons: montage, Io1, Io2, erupting volcano on Io, lava flows on Io
    • a close-up of the icy surface of Jupiter's intriguing Galilean moon, Europa
    • Some small moons of Jupiter: Thebe, Amalthea, & Metis. Amalthea is 200 km across.
    • Saturn: image from Voyager 2 (1982) and HST (approximate "natural" colors)
    • This image from the Cassini orbiter shows just how thin are Saturn's rings; they are also projected in shadow onto Saturn. Note also the presence of few of its moons.
    • Two of the moons of Saturn: atmosphere cloaked Titan, and Mimas with a 130 km crater.
    • Uranus: image from Voyager 2 (1986), and an infrared image from the VLT showing its rings and larger moons
    • Neptune: image from Voyager 2 (1989), and another one along with its moon, Triton
  • Mysterious Pluto & Charon....
  • Asteroids and their encounters with Earth
    • The Galileo probe visits two asteroids: Ida and Gaspra
    • A composite image of 3 asteroids. Gaspra is about 20 km long
    • The distribution of belt asteroids' orbital semi-major axes, and the Kirkwood Gaps
    • The NEAR probe orbits an asteroid for the first time: Eros, and another view. Eros is 33 km long.
    • This page has many more NEAR images of Eros
    • An illustration of the orbits of 100 of the known Earth-crossing asteroids
    • A map of known impact sites on Earth
    • A 290 million year old pair (32 km, 22 km) of impact craters in Canada
    • A 212 million year old 70 km impact crater, in Canada
    • A recent impact by a 50 meter iron meteor 1, 2, east of Flagstaff, AZ
    • Ground damage caused by the 1908 Tunguska airburst event
    • Web site illustrating & describing the 1908 Tunguska airburst event, based upon eyewitness accounts
    • A close-call over the Teton Mountains, 1972
    • The Peekskill fireball, October 1992
    • Daytime fireball over South Wales, UK, September 2003
    • This 1 km diameter asteroid passed within about 2 million km of Earth on 12/14/01
    • Some realistic scenarios of asteroid-Earth encounters
    • Leonid meteor debris vaporizing in Earth's atmosphere here, here and here
    •  And a good-sized Perseid meteor vaporizing at high altitude in Earth's atmosphere (courtesy of Rick Scott)
    • a bunch of links concerning meteor/comet encounters with Earth
  • Comets
    • An illustration of the Kuiper Belt, now observed, in relation to the planetary orbits
    • An illustration of the inferred Oort comet cloud
    • Comet Hale-Bopp: 1, 2, 3
    • Comet Halley's nucleus (1986 flyby of Giotto) and that of Comet Borrelly (2001 flyby of DeepSpace1)
    • a short gif movie of Comet Ikeya-Zhang (30 minute period on March 11, 2002)
    • Tidally shredded into 21 fragments (1.1 million km long chain) from an earlier orbital pass near Jupiter, comet Shoemaker-Levy 9 on a course of destiny with the giant planet. Here are the fireball plumes from fragments G and K, and the resulting temporary soot ``scars'' in Jupiter's atmosphere.

    Kirk Korista Professor of Astronomy
    Department of Physics
    Western Michigan University
    Kalamazoo, MI 49008-5252


    11/2/2016Problem Set 8 is the mid­Atlantic ridge, where mantle material emerges to the ocean floor and spreads out as new seafloor crust.Part JThis figure summarizes the geological histories of the terrestrial worlds. Based on this figure, what can you conclude?Hint 1.Study Section 9.6 ofThe Cosmic Perspective.ANSWER:CorrectNotice that size is the key factor in volcanism and tectonics. Impacts (show at the top) affect all worlds equally. The only geological process not shownis erosion, but we know that erosion depends on having an atmosphere, which in turn depends on having outgassing from volcanism (and tectonics).Sorting Task: Geological ProcessesPart AListed below are geographic features of the terrestrial worlds. In each case, identify the geological process: impact cratering, volcanism, erosion, ortectonics (where tectonics is any large­scale processes affecting the structure of the planetary crust),mostresponsible for the feature described. Match thegeographic feature to the appropriate geologic process.