Astronomy Exam 1 (Questions)
Which statement about the solar month and the sidereal month is correct?
the solar month is more than two days longer than the sidereal month
The fastest speed in the universe is:
the speed of light
Which of the following is NOT a result of the Earth's precession?
the stars twinkle when seen from the surface of planet earth
The star that provides energy for life on earth is ____
the sun
The strip of the sky through which the Sun, the Moon, and the bright planets appear to move in the course of a year is called
the zodiac
Astronomers discover a new comet that orbits the sun, but has its aphelion (the furthest point in its orbit) beyond Neptune. Astronomers studying this comet have the right t expect that it:
will follow Newton's laws of motion
The point in the sky directly above your head at any given time is called the
zenith
The point in the sky directs above your head at any given time is called the
zenith
How to convert AU to km
1AU = 150 million km
Light travels 3x10^5 meters every second. That number in words is
300,000 meters
The Renaissance astronomer who wrote the pioneering book that suggested the earth probably orbits the sun (instead of the other way around) was:
Copernicus
In March & September, where does the sun rise & set?
E to W
The first person who regularly turned a telescope to astronomical observations (and published his observations) was:
Galileo Galilei
When is the summer solstice?
June 21
Where on earth do stars always circle the zenith (and never rise and set)?
at the North Pole
Radio telescopes of modest size can't make out as much detail (have a lower resolution) than visible light telescopes. How do astronomers overcome this limitation?
we can connect several radio telescopes some distance apart together electronically to give us the resolution of a larger telescope
When is the spring equinox?
March 20
Even with the best and largest telescopes, we can't see all the stars in the Milky Way galaxy, even though these same telescopes can show us other galaxies. This is because
dust in the space between stars builds up over large distances and blocks the light of stars behind the dustier parts of the Milky Way
When is the winter solstice?
December 21
Of these, which is the largest? Universe, Jupiter, Milky Way Galaxy, Earth, Solar System
Universe
According to keepers third law, there is a relationship between the time a planet takes to revolve around the sun and its:
distance from the sun
When it comes to our place in the solar system today, which model do we accept?
heliocentric
All molecules (like molecules of water or carbon dioxide) are made up of
two or more atoms
The laws of nature (as determined by scientists) can be described many ways. Mark all that are correct
-are constructed from many observations, hypothesis, and experiments -apply both on earth and among the stars -are often written in the language of mathematics
Which of the following were done by Galileo Galilei? Mark all that are correct.
-discovering that Venus goes through phases (like the moon) -turning the telescope to the sky and believing what it showed his eyes -resolving the Milky Way into many, many stars -discovering 4 large moons around Jupiter
An astronomy textbook weighs four pounds on the surface of the Earth. After finishing your course, you are so tired of the book, you arrange for NASA to shoot it into space. If it is now twice as far from the center of the Earth than when you were reading it, what would it weigh? (Note, assume that the book is moving away from the Earth not falling freely around it.)
1 lb
A star is 230 light years away. The light we see tonight from that star left it
230 years ago.
What problem has precession caused for many of the schools of astrology?
Because of precession, the constellations are no longer lined up with the astrological signs that are named after them; since astrology was set up, the two have slipped one sign apart
Your friend, a graduate student in astronomy, is giving you a special tour of the local observatory. You notice that you are viewing the image from the big telescope from underneath the primary mirror; the beam of light has come through a small hole in the main mirror to an eyepiece below. This telescope uses what focusing arrangement?
Cassegrain focus
In Copernicus' day, people were worried about the idea that the celestial sphere seemed to turn around us once a day because the earth rotates. They argued that if the earth were to rotate so fast, it should fly apart. According to our textbook, what was one response Copernicus had to this worry?
Copernicus argued that the idea that the much larger celestial sphere is turning once a day (and the earth is not) meant that the celestial sphere would be torn apart even more
In what fundamental way did the work of Galileo differ from his predecessors who had thought about the sky?
Galileo used instruments and experiments to show him what nature was doing, instead of relying on pure logic
One of the great triumphs of spectroscopy was when astronomers identified a new element in the Sun (one that was only later found on Earth). Today, this element is called:
Helium
The scientist who worked out the mathematics of the connections between electricity, magnetism, and light in the 19th century was:
James Clerk Maxwell
The scientist who formulated the three laws of planetary motion by analyzing the data on the precise location of planets in the sky was:
Johannes Kepler
When NASA and a group of astronomers sent up a spacecraft designed to find planets orbiting other stars, they named it after Kepler. Why was this an appropriate name?
Kepler figured out the rules of planetary motion, which planets in our solar system and planets elsewhere must obey
In June, where does the sun rise & set?
NE to NW
The planet in our solar system whose orbit actually brings it inside the orbit of another planet is
Pluto
The star that is currently closest to the North Celestial Pole is
Polaris
The great astronomer of ancient times who summarized and improved a system of circles upon circles to explain the complicated motions of the planets (and published the system in a book now called the Almagest) is
Ptolemy
In December, where does the sun rise & set?
SE to SW
When is the autumnal equinox?
September 23
The natural object (not one that humans built) in space that's closest to earth is
The Moon
How does the sun influence the tides that we experience on earth?
The sun also raises tides on earth, but its effect is smaller than that of the moon
What is the cause of the seasons?
The tilt of the Earth's axis
What specific event really made it possible for the three laws of planetary motion to be discovered?
Tycho Brahe died and his assistant was able to get full access to his data.
The Balmer Series of lines in the hydrogen atom was very important in the history of physics and astronomy. What made it so important?
When electrons change levels to produce the Balmer series, the emitted light is in the visible part of the spectrum, so the lines were easy to see with our eyes
Which of the following is Earth NOT located in?
You can't fool me, we are located in all of these. (the solar system, the Milky Way galaxy, the local group, the virgo supercluster)
Which of the following has the greatest density?
a cubic meter of air
The location of the earth in the Milky Way galaxy is ____
a little less than 30,000 LY from the center
What type of telescope can be used routinely on the surface of the Earth during the DAY?
a radio telescope
This chapter discusses that light sometimes acts like a photon. What is a photon?
a self-contained "packet" of electro-magnetic energy
A large body in space that consistently makes its own light (instead of merely reflecting another body's light) is called
a star
From a particular location on earth, why can we see many more total eclipses of the moon than total eclipses of the sun?
a total lunar eclipse is visible over a much larger part of the earths surface than a total solar eclipse
The asteroid belt is
a zone where rocky chunks orbit between Mars and Jupiter
A dashing romanian count asks his sweetheart to marry him. She says she will give her reply when the moon is full. If he asked when the moon was at first quarter, how long will he have to wait?
about a week
Why is an image recorded with a CCD better for astronomers than an image recorded on photographic film or plates?
all of the info given about CCD's is correct
The smallest piece of an element (like gold or lead) that still has all the properties of that element is called
an atom
We now know that the orbit of a stable planet around a star like the sun is always in the shape of:
an ellipse
An artist who likes working with sources of light decides to make a modern sculpture out of electrified glass tubes that contain very thin (rarified) neon gas. When the sculpture is finished, and the electricity is turned on, the tubes glow with a rich red color. What we are seeing is:
an emission spectrum
The size of the device that collects radiation (such as light) is called a telescope's:
aperture
As seen from the continental United States, the Big and Little Dipper
are in the north circumpolar zone throughout the year
Based on the scientific and statistical tests of astrological predictions, which of the following statements is the most reasonable?
astrology has not passed any clear scientific or statistical test and as a result most scientists are very doubtful that it can predict anything meaningful about our lives
When the authors of our textbook say that astronomers are like police detectives trying to solve crimes, they are explaining that
both astronomers and detectives must test their hypotheses against any evidence that they gather
to come up with the precise mathematical form of his law of gravity, newton first had to invent the mathematical techniques that we now call:
calculus
The way scientists know that a hypothesis in astronomy is a reasonable description of nature is to
do experiments and observations about the predictions of the hypothesis
eccentricity formula
e=c/a c: distance from center to focus (sun) a: semi major axis (center, through other focus, to edge of ellipse)
In the 19th century, it became clear that magnetism was not a separate force, but was always produced by the action of
electric charges that were in motion
By the term universe, astronomers mean
everything that we can observe
You are on a camping trip, far away from city lights. You look up into the dark night sky, and see lots of stars, some brighter, some dimmer. All the stars you see with your unaided eye are
in the Milky Way Galaxy
One reason that human eyes evolved to detect visible light is:
it is a band of the spectrum where the sun puts out a great deal of energy
At the largest and most modern astronomical observatories on Earth today, which of the following regularly happens to the image formed by the telescope?
it is recorded using an electronic detector called a CCD for later analysis
To figure out what you weigh on the surface of the moon (how much gravity there pulls you downward), you need to know
just the size of the moon's orbit around the earth (its semi-major axis)
In the northern hemisphere, the altitude (height in degrees above the horizon) of the North Star is always roughly equal to the
latitude of the observer
We have two waves of light, A and B. Wave A has a higher frequency than wave B. Then wave B must have:
longer wavelength
In locating objects on the celestial sphere, we call the number of degrees east or west that something is from Greenwich, England its
longitude
According to the geocentric view, everything in the heavens had to go around the earth, which was the center of the universe. What objects did Galileo discover with his telescope that clearly didn't go around the earth?
moons around the planet Jupiter
In Newtons law of gravity, the force of gravity goes up ad the:
more than one of the above
Some Canadian troops are sent (as part of a U.N. peacekeeping force) to a country located on the Earths equator. At night, when homesickness makes them gaze sleeplessly at the stars, which of the following will be familiar to them (the same at the equator as in Canada)
none of these are the same on the equator as in Canada
When a comet like Hale-Bopp comes closest to the sun in its orbit, we say that it is at:
perihelion
How could you make an ordinary atom that is minding its own business into an ion?
remove one or more electrons from the atom
When a planet temporarily moves westward in the sky over the course of several weeks or months (instead of eastward, as it typically does), we call it:
retrograde motion
A serial killer from a strange cult that follows astrology only kills his victims when the Moon is full. He leaves a note on the body of his latest victim, explaining that the murder was committed when the Moon was rising. What time of day did the murder take place?
roughly around sunset
A writer of mystery novels wants to portray something gruesome happening just as the full moon is at its highest point in the sky. What time of day will the gruesome event occur?
roughly midnight
The astronomical unit (AU) as defined by astronomers is
the average distance between the earth and the sun
A graduate student in geology who grew up in Florida (near the southernmost tip of the United States) gets to accompany her research professor to the North Pole. What will be different at the North Pole from the way she remembers the sky in Florida?
the celestial pole is overhead
When a knowledgeable amateur astronomer tells you that she has a 14-inch telescope, what does the number 14 refer to?
the diameter of the primary lens or mirror
Newtons reformulation of Keplers third law allows us to measure the masses of bodies in orbit around each other, if we can measure:
the distances and periods of revolution
In an ellipse, the ratio of the distance between the foci and the length of the major axis is called _______.
the eccentricity
Every celestial object appears to go around the Earth once a day. In addition to this motion, which celestial object has the fastest apparent motion in the sky?
the moon
Which of the following statements about the nucleus of a typical atom (such as a carbon atom in your little finger) is FALSE:
the nucleus repels the electrons which move around it
For scientists, an element (like gold) is defined by
the number of protons in its nucleus
Most ultraviolet radiation does not penetrate to the Earth's surface. Instead it is absorbed in:
the ozone layer
In Ptolemy's system the planets orbit the earth rather than the sun. How did this system explain the retrograde motion of planets like Jupiter?
the planets moved on a small circle whose center, in turn, circled a point near the earth
Which of the following statements about electromagnetic radiation is FALSE?
the radiation consists of tiny charged particles given off by the nuclei of atoms
Which Ancient Greek thinker suggested (long before Copernicus) that the Earth is moving around the sun?
Aristarchus
The earth is closest to the sun in which month of the year?
January
Some college students decide to form a secret society that would meet each year after graduation at a time when the day and night were the same length. Which of the following would be a time they could meet?
September 23
The 88 sectors into which astronomers today divide the celestial sphere (the whole sky) are called:
constellations
How fast do electromagnetic waves travel?
speed of light
A light year is ____
the distance light travels in one year
The celestial sphere turns once around each day because
the planet on which we live is rotating
