Download Review for Exam 1

Review for Exam 1
1
How do you measure angular distances between stars and how do you measure
angular sizes of objects such as the sun, the moon, etc? What is an arc minute and an
arc second.
What is the celestial sphere, the celestial horizon, zenith, north celestial pole, celestial
equator?
What is latitude, longitude, altitude, azimuth, declination, right ascension?
How do the stars appear to move in the sky as a result of the earth’s rotation. How does the
sun appear to move in the sky due to the earth’s orbit around the sun? What is the ecliptic?
How fast the sun moves eastward among the stars? What are the zodiac constellations?
6
What causes the occurrence of seasons on the Earth?
What causes the phases of the moon? What are the angles of the earth, moon and the sun
At full moon, new moon, a quarter moon.
What is precession of the earth’s axis and how long it takes to complete one cycle. What are
the consequences of this precession?
Applications of the small angle formula:
Something which is 500 km away has an angular size of 5 seconds of arc.
Approximately how tall is it?
What is believed to be the contribution of the Greek astronomer Aristarchus?
What are the reasons why the other astronomers rejected his Heliocentric model?
What quantities did he calculate?
How did Eratosthenes determine the size of the Earth?
What evidence did Aristotle offer for his argument that the Earth is a sphere?
An astronaut lands on an unknown planet. After walking a distance of 50 km toward the north
pole of the planet, she notices that the pole star for that planet is 1 degree higher in the sky.
What is the circumference of the planet?
9
What were epicycles and why they were used in Ptolemy's model of the solar system?
What are Copernicus’s main contributions to astronomy?
What are Tycho Brahe’s main contributions to astronomy?
Which are Kepler's Laws of Planetary Motion?
3
A hypothetical planet orbits the sun a distance of 1 light-year. What is its orbital period?
When is retrograde motion of the planets and how can it be explained? How does the ancient
geocentric model explain it?
What are the main Galileo's contributions to astronomy?
Which are the Newton’s laws of motion? What is acceleration? How does the force of gravity
depend on the distance between two bodies and their masses? What is the direction of the
force required to keep an object in a circular orbit?
What are the causes of tides and when they are strongest?
What is the wavelength, the frequency and the velocity of an electromagnetic wave?
How are they related?
What is the Doppler effect?
What are the various types of mirrors and lenses? How do they work?
What are the various types of telescopes? How does a telescope work? What is the lightgathering power, resolution and magnification of a telescope?
2
How does the light gathering power of a 4 inch telescope compare to that of a 12 inch
telescope?
7
Suppose a source of electromagnetic waves is moving away from us at 2% of the speed of
light. What can be said of the wavelength of the waves we receive from the source?