Question 1

Which astronomer developed the three laws of planetary motion?

Accepted Answer

A)   Kepler
B)   Newton
C)   Galileo
D)   Brahe A

Question 2

The law of universal gravitation was formulated by ___________.

Accepted Answer

A)   Galileo
B)   Kepler
C)   Newton
D)   Brahe C

Question 3

Briefly discuss the various motions of Earth. What motion is often mistakenly credited for causing seasons here on Earth? How are these motions related if at all. to the modern calendar that we use today?

Accepted Answer

The two primary motions of Earth are rotation the turning of earth on its axis. and revolution the motion of Earth along a path around the Sun.. The Earth's distance from the Sun, which is caused by revolution, is mistakenly thought to be the cause of seasons. In fact, the tilt of the Earth on its access is the cause of seasons. When the Southern Hemisphere is tilted towards the Sun and the Northern Hemisphere is tilted away from the Sun, the Southern Hemisphere experiences summer while the Northern Hemisphere experiences winter. The same applies for the opposite scenarios. These processes contribute to creating seasons and our modern calendar.

Question 4

According to the Ptolemaic Greek. model of the universe, how many "heavenly" bodies could be observed wandering along the background of stars?

Accepted Answer

A)   seven
B)   two
C)   five
D)   one

Question 5

The 5000 year old Stonehenge stone circle of Salisbury Plains, England, allows light shafts to come straight between two rocks on___________ in the Northern hemisphere.

Accepted Answer

A)   summer solstice
B)   fall equinox
C)   winter solstice
D)   spring equinox

Question 6

Using the telescope, Galileo discovered that the planet ___________had polar ice caps not unlike those on Earth.

Accepted Answer

A)   Venus
B)   Saturn
C)   Mars
D)   Jupiter

Question 7

The apparent shift in the position of a nearby star when viewed from extreme points in Earth's orbit six months apart is called___________.

Accepted Answer

A)   stellar parallax
B)   astronomical unit
C)   gravitational attraction
D)   angular distance

Question 8

The earliest astronomical records appear to have been made by the ancient Chinese, Egyptians, and Babylonians in order to ___________.

Accepted Answer

A)   predict the best dates for traveling, particularly by boat, and where to build temples
B)   determine who should be sacrificed or promoted based on heavenly signs at their birth
C)   determine when to plant crops or hunt animals based on seasonal changes
D)   predict future positions of celestial objects to identify good or "lucky" dates for various important events

Question 9

The belt of constellations through which all the planets move is called the ___________

Accepted Answer

A)   Planetoid
B)   Milky Way
C)   Cosmos
D)   Parallax
E)   Zodiac

Question 10

When the Sun crosses the celestial equator, and day and night are of equal length around the globe, it is the time of the___________.

Accepted Answer

A)   equinox
B)   aphelion
C)   solstice
D)   perihelion

Question 11

According to the Ptolemaic Greek. system, the planets have ___________orbits.

Accepted Answer

A)   elliptical
B)   heliocentric
C)   random
D)   circular

Question 12

At the beginning of spring, the vernal equinox, what is the right ascension of the Sun?

Accepted Answer

A)   0
B)   90 degrees
C)   18 hr
D)   12 hr

Question 13

A sidereal day is defined as___________ .

Accepted Answer

A)   the time for one complete revolution of the earth relative to the celestial reference
B)   24 hours at Greenwich, England
C)   24 hours in a day
D)   the time between periods when the Sun is at the exact same height in the sky, for example, noon

Question 14

The apparent westward drift of the planets as compared to the background stars is called___________ motion.

Accepted Answer

A)   retrograde
B)   altitude
C)   perihelion
D)   synodic

Question 15

Earth is closest to the Sun in___________ .

Accepted Answer

A)   April
B)   October
C)   July
D)   January

Question 16

___________discovered the three laws of planetary motion.

Accepted Answer

A)   Brahe
B)   Galileo
C)   Kepler
D)   Newton

Question 17

At first quarter it is approximately ___________weeks. until the new Moon.

Accepted Answer

A)   1
B)   2
C)   3
D)   4

Question 18

Use Figure 21.26 below to help explain the difference between the sidereal and synodic month. In the second position the Moon has moved to the other side of Earth and it says "day 14 ^¾full Moon". In the thi position the Moon is back on the Sun's side of the Moon. It is labeled "day 27 ^¼Earth, Moon and distant star are once again aligned Siderelal month. and then a second Moon 2 days separated from the first that says "day 29 ^½, new Moon synodic month.. The angle to distant star is now upward.

Accepted Answer

The answer of Use Figure 21.26 below to help explain...

Question 19

A statement you will sometimes hear people say is that a day is not 24 hours but is really 23 hr. 56 min. and 4 sec. What does this refer to?

Accepted Answer

A)   This is sidereal time, not solar time; a solar day is 24 hours.
B)   The original definition of the hour was off, and with more accurate atomic clocks we now realize the real day is this length.
C)   It is just an urban myth; the day really is 24 hours long.
D)   Our clocks drift that much each day, and we average out the affect with period time shifts, like leap years and leap seconds.

Question 20

A total eclipse of the Sun is only possible at ___________.

Accepted Answer

A)   second quarter
B)   new Moon
C)   third quarter
D)   first quarter

Exam 21: Origins of Modern Astronomy