ASTRONOMY 101

Prof. Welsh's Astronomy 101 Exam #1 Information

** Version 2.2 **
(minor typos fixed from V2.0)
Exam #1 Friday Feb 22

This is a 50-question multiple-choice exam. Bring a clean, uncrumped ParSCORE Student Enrollment form (the larger 6"x11" pink form), some #2 pencils & an eraser. If you use the non-enrollment form, you will lose a minimum of 5 points. This is a "closed-book exam". No calculators/PDAs/ipods/cell phone/etc. are allowed.
** Fill out your ParSCORE form before the exam starts. Be sure to put your Red ID on both sides of the form, and don't add an extra zero to the front of your Red ID number. Leave the last column empty. Fill in "Test Form A" and "Exam # 001". (Don't enter your phone number or a test code on the front of the form.) Enter your name, but don't worry about filling in the bubbles - just your name is fine. You will lose 1 point for each mistake in filling out the ParScore form. Please be careful and don't throw away points!! Common errors include:
. putting an extra zero in front of your Red ID
. putting a blank in front of your Red ID
. incorrectly entering your Red ID
. not filling in Exam 001
. accidentally filling in two answers
. not erasing an answer fully
Please be careful!

** The class notes are the most imporant source of information for this exam. **

Material you will be responsible for:
+ All class notes
+ Textbook: Chapters 1, 2, 3, 4 and parts of 5.
+ All homework assignments, including observational "Look at the sky" homework, all reading assignments.

Material you can SKIP FOR THIS EXAM:
- the big bang and the expanding universe sections in Chapter 1
- angular momentum (page 89-90)
- section on E=mc² (page 93)
- Ch 5 "What is matter?" p 110-111
- Ch 5.2 "Learning From Light" (spectroscopy, thermal radiation, Doppler effect) p 113-121
- Ch 5 Adaptive Optics and Interferometry p 129

And you can also skip the following concepts:
- trigonometric details of how Aristarchus measured the relative distances of the Moon and Sun
- atmospheric drag and escape velocity (page 97)
- predicting eclipses and the saros cycle (page 45)
- the lunar calendar and the Metonic cycle (page 58)
- sidereal vs synodic periods
- line of nodes
- conic sections
- Table 4.1 Energy comparisons

Some questions to help guide your studying:
- What causes the seasons?
- At what phases of the Moon can eclipses occur?
- At what time is the waning crescent Moon on the meridian?
- What is a zenith? What is a solstice?
- What is a nanometer? a light year? an AU?
- What is the speed of light? (know this in cm/s, m/s and km/s)
- What is the north celestial pole?
- Which planets were known to the Greeks and Babylonians?
- What is a constellation?
- What did Hipparchus do?
- What does heliocentric mean?
- What are the equinoxes?
- What is a solstice? When do they occur?
- What is retrograde motion?
- What is "Occam's Razor"?
- How did Eratosthenes measure the circumference of the Earth?
- Who was Ptolemy and what did he do?
- Who was Copernicus and what did he do?
- What is stellar parallax?
- What are Kepler's Laws?
- If you double a planet's semimajor axis what happens to its orbital period?
- If a planet has a period of revolution of 12 years, what is its distance from the Sun?
- What was the significance of Galileo's observations of Venus? Of Jupiter?
- Law of Gravity: e.g., What happens to the force if the distance is tripled?
- What is the difference between mass and weight?
- What is an arcsecond?
- What is an epicycle?
- What is eccentricity?
- What is the ecliptic?
- What is an ellipse
- What does the symbol "a" mean in Kepler's 3rd Law?
- What were the discoveries of Galileo?
- What color does the star Betelgeuse *appear to be to the naked eye*?
- At what time is the full Moon on the meridian?
- At what time does the full Moon rise?
- At what time does the waning gibbous Moon set?
- Why can't the textbook publishers put the position of the planets on the star charts?
- What celestial objects do the names of the days of the week correspond to?
- How are energy and frequency related for light waves?
- How are energy and wavelength related for light waves?
- What is visible light?
- What is the difference between infared, ultraviolet and gamma rays?
- What is radio light?
- Why do stars twinkle?
- What do astronomers put telescopes in space?
- What are the different kinds of telescopes?
- How much energy is in a wave or photon of light?
- What is a focal length of a lens?
- What is the diffraction limit and how does it relate to resolution?
- Why do astronomers want to observe the sky in X-rays? In radio waves?
- What is refraction?
- What is a refractor?
- What is a spectrum?
- What is a the visible spectrum?
- What is Right Ascention (RA) and Declination (dec)?
- Why don't we have eclipses every new and full Moon?
- How does the energy of a photon change if you triple its frequency?
- How much does the force of gravity change if you triple one of the masses and and triple the distance between the masses?
- If you doubled a satellite's distance from the Earth, how would its orbital period be affected?
- What is "synchronous rotation"?
- Suppose "planet X" is discovered and is 10 times further from the Sun than the Earth is. How long is a "year" on Planet X?
- What is the "VLA"?
- Why do astronomers use relector-type telescopes instead of refractors?
- What is the difference between a planet and a star?
- What is the difference between the solar system and a galaxy?

General hints for exam preparation and earning a good grade in this course:
- Go to the Astronomy Help Room
- Read the "Summary of Key Concepts" section at the end of each chapter several times.
- Know all the definitions on page 5 (except expansion of the universe - skip that for now)
- Go to the Astronomy Help Room
- Skip concepts that were never mentioned in class. (For example, we never talked about the "synodic period" or "nodes" or "penumbra" or "momentum", etc.)
- Review the homework questions/answers.
- Come to my office hours for help.
- Go to the Astronomy Help Room - Don't be shy, go!

GOOD LUCK!