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Astronomy Final
ASTRONOMY 105
39
Astronomy
Undergraduate 1
12/17/2010

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Term
A scientist observes a new phenomenon that disagrees with the scientist's own explanation or hypothesis. Following the scientific method, the correct procedure is to
Definition
modify the hypothesis
Term
Modern science is founded
Definition
in part on the philosophical approach of the ancient Greeks.
Term
Forms of radiation which are not visible
Definition
have allowed us to determine much of what we now know about the universe.
Term
So far, our study of the other bodies in our solar system is based upon
Definition
telescopic observations from Earth and spacecraft plus geologic samples brought back from the Moon.
Term
The lifetime of a typical star (like our Sun) appears to be
Definition
a few billions of years
Term
Heavy elements, such as those throughout Earth and within our bodies, appear to have been formed
Definition
deep inside some now vanished star
Term
How many arcseconds are there in a full circle?
Definition
3600
Term
An astronomer finds an object at a distance of 5.6 pc from Earth. Based on the distance, which of the following is this object most likely to be?
Definition
a star in our galaxy
Term
An underlying theme of astronomy is that the
Definition
entire universe is governed by a single set of fundamental physical laws.
Term
In modern astronomy, the constellations are
Definition
88 regions of the sky, covering the whole sky.
Term
The zenith defines a direction
Definition
vertically above an observer.
Term
Earth would not have seasons if
Definition
its axis of rotation were perpendicular to its orbital plane.
Term
When the Sun is at one of the equinoxes,
Definition
day and night are of equal length everywhere on Earth.
Term
The zodiac is a
Definition
band of sky extending 8° on either side of the ecliptic.
Term
What is the significance of Polaris, the North Star?
Definition
Polaris is almost on the curve traced out by the rotation axis as a result of the precession of the rotation direction.
Term
Precession of Earth's axis of rotation is caused by
Definition
the gravitational pull of the Moon and the Sun on the equatorial bulge of Earth.
Term
If the daytime sky were not bright, in which direction would we see the Sun move along the ecliptic over the course of a year, relative to the background stars?
Definition
toward the east
Term
To what constellation will the north celestial pole be closest in the year 14,000 A.D.?
Definition
Lyra
Term
Sidereal time is the more fundamental time, since it is a measure of the true rotation rate of Earth. Why then do we govern our lives by solar time rather than sidereal time?
Definition
We wish to remain in time with the Sun's illumination on Earth, with high Sun angle at about midday every day.
Term
At what approximate time will the new moon rise?
Definition
sunrise
Term
As seen by a distant observer who is fixed with respect to the stars, approximately how long does it take for the Moon to rotate once around its own axis?
Definition
1 month
Term
The term “sidereal month” refers to the
Definition
time over which the Moon completes one orbit around Earth, relative to the stars.
Term
During a lunar eclipse the
Definition
Earth comes between the Sun and the Moon.
Term
A lunar eclipse does not occur at every full moon because
Definition
the plane of the Moon's orbit is at an angle to the plane of Earth's orbit.
Term
The line of nodes of the Moon's orbit is the line of intersection between the orbit with the
Definition
ecliptic plane.
Term
When in total lunar eclipse, the Moon shows a reddish color because
Definition
only the red part of the solar spectrum is deflected onto it by Earth's atmosphere.
Term
Assuming clear skies everywhere, a total solar eclipse is visible
Definition
only to people in a long narrow path much smaller than a hemisphere.
Term
An observer can see a total solar eclipse from within a narrow band along Earth's surface. This band
Definition
can begin almost anywhere on earth's surface
Term
At the ancient Egyptian city of Syene the Sun was directly overhead only at summer solstice. Thus, Syene must have been very close to
Definition
the Tropic Of Cancer
Term
The ancient Greek thinker Pythagoras held the view that
Definition
natural phenomena could be described mathematically.
Term
Planets move past the background stars as seen by someone on Earth. What is the normal direction of this motion?
Definition
west to east because of the motion of the planet along its orbit
Term
Retrograde motion of a planet is
Definition
westward motion against the star background
Term
Nicolaus Copernicus was the first person to
Definition
develop a mathematical model for a Sun-centered solar system.
Term
When Venus is at inferior conjunction,
Definition
it is at its smallest distance from Earth.
Term
Which of the following planetary configurations can an inferior planet never reach?
Definition
opposition
Term
The greatest inaccuracy in Copernicus' theory of the solar system was that he
Definition
placed the planets in circular orbits
Term
A significant contribution of Kepler to our understanding of the solar system was
Definition
discovery that planetary orbits are not circular
Term
What did Galileo see when he observed Venus through his telescope?
Definition
Venus has phases like the Moon and has its largest angular diameter at crescent phase.
Term
In which direction would Earth move if the Sun's gravitational force were suddenly removed from it?
Definition
in a straight line along a tangent to its circular orbit
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