Download Astronomy 103 Review Sheet 1

REVIEW SHEET: ASTRON 103, PART I.
Apparent Motions in the Heavens; (actual motions responsible)
Daily Motion (Earth’s rotation on its axis)
Annual Motion of the Sun (Earth’s revolution around the Sun)
Precession of the Equinoxes (wobble of Earth’s axis – 26,000 years)
Seasons
Tilt of earth’s axis (23.5°)
How angle of sunlight, number of hours of daylight, vary during year
Vernal, Autumnal Equinoxes; Summer, Winter Solstices
Moon
Phases
Waxing (New Moon to Full Moon)
Waning (Full Moon to New Moon)
Difference between Moon’s sidereal, synodic periods
Eclipses
Solar eclipses (mode of occurrence; kinds)
Lunar eclipses (mode of occurrence; kinds)
Why eclipses aren’t seen every month
Tides
Reason for twin bulges (action of Moon’s gravity on Earth, oceans)
Celestial Sphere
North, South Celestial Poles
Altitude of North Celestial Pole [Polaris] (how varies as function of latitude)
Celestial Equator; Ecliptic
Horizon Coordinate System: Altitude, Azimuth
Equatorial Coordinate System: Right Ascension, Declination
Ptolemy’s geocentric model of Universe
Explanation for retrograde motion
Copernicus’s heliocentric model of Universe
Explanation for retrograde motion
Kepler’s Three [empirical] Laws of Planetary Motion
Elliptical orbits
Area Law
Harmonic Law: P2 = a3
Newton’s Three Laws of Motion
Law of Inertia
Force Law
Law of Action-Reaction
Newton’s Law of Gravity (obeys inverse-square law)
Analogy between apple, moon (argument for universal gravitation)
Newton’s version of Kepler’s Third Law
Escape Velocity
Einstein, Relativity Theories
Special Theory (1905) – length contraction, time dilation, mass increase
General Theory (1916) – equivalence principle
Electromagnetic Spectrum
Relation between speed (c), frequency (f), and wavelength (λ)
Relative energies, frequencies, wavelengths.
Light; Color-Temperature relations
Wien’s Law; Stefan-Boltzman Law
Spectra
Continuous
Emission (bright) line
Absorption (dark) line
Doppler Effect
Optical Telescopes
Refractors, Reflectors
Magnification
Light Grasp
Angular Resolution
Ground-based vs. space-based
Sample Questions – Exam I
1. The Sun’s apparent position against the background stars changes throughout the
year because of the ________.
a.
b.
c.
d.
Earth’s daily rotation
Earth’s revolution around the Sun
tilt of the Earth’s axis
precession of the equinoxes
2. When the Moon reaches its Full phase, it ________.
a.
b.
c.
d.
rises at midnight
rises and sets with the Sun
sets at midnight
rises at sunset and sets at sunrise.
3. Newton’s Second Law of Motion states that ________.
a. force is the product of mass and acceleration
b. for every action, there is an equal and opposite reaction
c. objects at rest, or in uniform motion, will remain in that state if no
outside forces act upon them
d. the force of gravity between any two masses decreases with the square of
the distance between them
4. What approximate range in wavelengths is the human eye sensitive to?
a.
b.
c.
d.
100-300
300-400
400-700
700-900
nm
nm
nm
nm
5. A telescope that collects and focuses light with one or more lenses is called a
________.
a.
b.
c.
d.
reflector
Newtonian
Cassegrain
refractor
6. Match the astronomers’ names with their contributions below.
a. Ptolemy
____ Made the most precise observations of the planets
b. Newton
____ Explained retrograde motion with epicycles & deferents
c. Tycho Brahe
____ Invented a reflecting telescope
ANSWERS: 1:b
2:d
3:a
4:c
5:d
6: c
a
b