Astronomy Terms From Chapter 2 Lecture

Front 1

An attempt to explain what we observe in nature

Back 1

Science

Front 2

A valid scientific explanation must be...

Back 2

testable and consistent

Front 3

Single assertion or conjecture that must be tested by making oservations or performing experiments

Back 3

Hypothesis

Front 4

System of rules and principles that can be applied in a variety of circumstances

Back 4

Theory

Front 5

Theory that has been refined, tested, and confirmed so often that scientists have confidence in it

Back 5

Natural law

Front 6

Carefully devised mental conception of how something works

Back 6

Scientific model

Front 7

What characterizes as a scientific hypothesis?
A. It is based on the ideas of the smartest people
B. The more ancient the wisdom, the better the explanation
C. It is based on observations
D. It is tested through prediction and experiments
E. Both C and D

Back 7

E. Both C and D

Front 8

What is the difference between the word <i>theory</i> as used in everyday speech, and the word <i>theory</i> as used in science?
A. Theory, in common speech, is something uncertain (It's just a theory")
B. A <i>scientific theory</i> has b een thoroughly tested
C. A <i>scientific theory</i> must not conflict with other accepted theories
D. A <i>scientific theory</i> must be discarded if it fails to explain what is observed in <i>any</i> experiment
E. All of the above

Back 8

E. All of the above.

Front 9

Subjective measure of brightness, depends on physiology of eye and psychology of perception

Back 9

Apparent visual magnitude

Front 10

More accurate measure of brightness, measure of the light energy from a star that hits 1 square meter in 1 second

Back 10

Intensity

Front 11

great circle on celestial sphere that passes through an observer's zenith and the north (or south) celestial pole

Back 11

Meridian

Front 12

What makes Polaris a special star?
A. It is the brightest star in the sky
B. It is currently near the axis about which the sky turns
C. It's azimuth (direction) is always due north
D. it is always directly overhead, no matter where you are
E. Both B and C

Back 12

E. Both B and C

Front 13

If Orion rises at 8:00 PM tonight, what time will it rise tomorrow night?

Back 13

7:56. A solar day exceeds a sidereal day by 4 minutes, so objects in the sky appear to rise about 4 minutes earlier each night

Front 14

Why do we have seasons on Earth?
1. The Earth is closer to the Sun in summer
2. The tilt of the Earth makes sunlight strike the surface more directly in the summer
3. Neither of the above.

Back 14

2. The tilt of the Earth makes sunlight strike the surface more directly in the summer

Front 15

"equal night," points where ecliptic intersects celestial equator

Back 15

Equinox

Front 16

"sun stand," point on celestial sphere where the Sun raches its greatest distance north or south of the celestial equator

Back 16

Solstice

Front 17

What causes the seasons?
A. in summer, theh whole Earth is closer to the Sun
B. In summer, the tilt of the Earth's axis makes the part of the Earth we are on closer to the Sun.
C. in summer, the sun is up for more hours
D. In summer, the sun climbs higher in the sky, so its rays hit the ground mroe directly
E. Both C and D

Back 17

E. Both C and D

Front 18

Which way do outer planets (Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto) generally appear to move along the Ecliptic?

Back 18

Eastward

Front 19

When can Mercury and Venus, the inner planets, be seen?

Back 19

The inner planets, Mercury and Venus, can never be seen at large angular distance from the sun and appear only as <i>morning</i> or <i>evening stars</i>.