(Don't Use Canvas to contact me, use email link)
Office: LD 156-S, 278-9244
Class: LD 030, Monday and Wednesday from 12:00 - 1:15
4 questions, multiple choice, review your notes from previous four lectures
In no less than 1500 words, TYPED, submitted as PDF (not Word or txt, etc.) to bwoodahl@iu.edu, explain in your own words the "Bethe Weizsacker Cycle". Make sure your paper includes a short discussion where you contrast it with the Proton-Proton Chain which occurs in the Sun. Note: Your submittal will be scanned by Grammarly Faculty Services for verification of original content. Include your full name, the due date is Friday April 3rd at 12:01 PM (Noon). These points will be added to your lowest exam score. Late submittals are not accepted.
The Ahnighito Meteorite from Greenland (34 tons), Displayed at New York Museum of Natural History
Nucleus of Comet Vilt-2 Photographed by Spaceprobe Stardust in 2004
Comets Come From Oort Cloud and Kuiper Belt (Previous Image)
Comet SL9 Impacting Jupiter in 1994 as seen from Io (Rendition)
This ends Exam 2 material.
4 questions, multiple choice, review all your notes from the past four lectures
Jupiter's Three Cloud Levels: Ammonia, Ammonium Hydrosulfide, Water
Source of Io's Heat: Elliptical Orbit and Jupiter's Tidal Forces
Saturn's Titan: Nitrogen and Methane Atmosphere (Photo NOT Color-Corrected)
Huygen's Spaceprobe Reveals Some of Titan's Surface Features
4 questions, multiple choice, review all your notes from the past three lectures
Atmospheric Scattering of Light: Blue Daytime Skies and Red Dawn
Mars' Orbital Ellipticity: Hemispherical Asymmetry in the Seasons
Water Ice & Trace Amount of Dry Ice in Mars' North Pole Ice Cap During Northern Hemisphere Summer
4 questions, multiple choice, review your notes from the last two lectures
Mars' Ancient Water Erosion by Rainfall: Lack of Small Craters
Evidence for Water Today (Oct 2005) on Mars: High Resolution Picture 1
Evidence for Water Today (Oct 2005) on Mars: High Resolution Picture 2
Evidence for Water Today (Oct 2005) on Mars: High Resolution Picture 3
Evidence for Water Today (Oct 2005) on Mars: High Resolution Picture 4
New Images for Water on Mars (Sep 2015): High Resolution Picture 1
New Images for Water on Mars (Sep 2015): High Resolution Picture 2
Venus' Surface Close-Up from Soviet Union's Venera Lander Using an Optical Imager
About 70 multiple-choice questions, review all your notes and quizzes
Bring a pencil and a scientific calculator (iPhones etc. are not allowed)
ZipGrade (optical scan) sheets will be provided, pick one up when you enter
4 questions, multiple choice, review your notes from the last three weeks (this will also help prepare for the exam)
Know everything about light
Know about the fundamental particles (and other aspects of matter)
Understand the distinction between chemical and nuclear reactions
4 questions, multiple choice, review your notes from the past two weeks
Know all about Newton, his Laws of Motion, and his Law of Gravity
Photon (wavy line) Being Absorbed by Atom -> Electron (solid blue line) Jumps Up into Higher Orbit
Atom Emitting a Photon (wavy line) -> Electron (solid blue line) Jumps Down into Lower Orbit
4 questions, multiple choice, review your notes from the past four lectures
Know the history of Foucault, Galileo, Kepler, Brahe, Copernicus
Know the numbers/info regarding galaxies, and stars in galaxies
Know the motion of Earth's path around Sun (ecliptic plane, perihelion = closest to the sun, etc.) and the seasons
Know about the Moon's motion around the Earth and the phases of the Moon
4 questions, multiple choice, review your notes from last week, know:
The metric prefix names for various powers of ten
Dividing two numbers and obtaining the "order of magnitude"
The number of stars in a galaxy and the number of stars in the observable universe
The speed-of-light in the metric units (3 x 10^8 meters/second)
Syllabus (PDF). Please print and keep with your notes.
Master Schedule (PDF). Please print and keep with your notes.
These documents may be updated during the semester. Please check that you have the latest versions.
A solar eclipse only occurs if the New Moon is about within half a degree of the ecliptic plane (defined by the orbit path of Earth as it travels around the Sun). The Moon's orbital path, around the Earth, is (unfortunately) inclined by about 5 degrees to the ecliptic. Thus, there are only two opportunities each moonth (punning) when the Moon passes through the ecliptic. These points are called the nodes (ascending, descending). The Moon passing through a node is not sufficient, it must pass through the node during the New Moon lunar phase.
About twice a year, during an approximately 45 day window (based upon the orbital speeds of the Earth and Moon), the New Moon is close enough to a node that a solar eclipse can occur. Further complicating the motion, the Moon's orbital plane precesses relative to the ecliptic. Hence, the nodes precess around the ecliptic, completing one rotation about every 18.6 years. In addition, because the Moon's path around Earth is elliptical, during many solar eclipses the angular diameter of the Moon is not large enough to fully cover the Sun. Only when the New Moon is near a node and near perigee (i.e. closest to the Earth), does totality occur. On average, it takes about 400 years for totality to occur again at the same geographical location.
Department of Physics, IUI - Updated on Mar 11, 2026 at 1:25 PM EDT
