Astronomy

Galileo discovered:

- turning the telescope to the sky and believing what it showed his eyes - discovering four large moons around Jupiter - discovering that Venus goes through phases (like the Moon) - resolving the Milky Way into many, many stars

Where has frozen water has been discovered on the Moon?

Deep inside craters in the regions near the Moon's poles

Which of the following has the greatest average energy of random atomic and molecular motion? a. a cube of ice b. a cube of water c. a cube of steam d. a cube of air (on Earth) e. a cube of the Sun

E. a cube of the Sun

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

The average temperature on planet Earth is higher than you would expect just from the heating of sunlight alone. What is the explanation for this?

carbon dioxide (and other gases) in the atmosphere cause a greenhouse effect

Ancient astronomers divided the sky into regions containing distinct groups of stars called

constellations

The 88 sectors into which astronomers today divide the celestial sphere (the whole sky) are called

constellations

What is one way that astronomers have actually gotten an idea of the age of the surfaces of terrestrial planets other than the Earth?

counting craters

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?

prime focus

I want to examine the surface of a planet which is completely covered by a thick layer of clouds all the time. What wavelength of electromagnetic radiation would I be smartest to use

radio waves (like radar)

When a star or galaxy is moving away from us, we observe the Doppler effect by seeing the lines in its spectrum

red-shifted (shifted toward the red end of the light spectrum)

All the planets (without exception)

revolve around the sun in the same direction

Regions where the continents or the sea floor are pulling apart are called

rift zones

If you want to locate someone precisely on the surface of the Earth, you specify her exact latitude and longitude. If you want to locate a star precisely on the sky, you need to specify its exact:

right ascension and declination

How does plate tectonics work?

slow motions within the mantle of the earth move large sections of the crust around

The process of breaking visible light down into its component colors creates a

spectrum

In its overall composition, the Moon roughly resembles

the Earth's crust and mantle

Mercury is a small planet and therefore has trouble holding on to an atmosphere. How then do scientists account for the extremely thin atmosphere that was found around the planet in 1985?

the Sun's "wind" of particles is chipping atoms off the surface of Mercury

Of the following, which has the highest resolution (ability to make out fine detail):

the Very Long Baseline Array of Radio Telescopes, stretching from the Virgin Islands to Hawaii

The Moon is heavily cratered, but the Earth which "lives next door" is NOT. Why?

the active geology and weather on Earth destroy traces of impacts over millions of years

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

Newton's reformulation of Kepler's 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

Scientists now understand that the Earth consists of layers, with the densest materials in the core. What allowed the differentiation of the Earth's layers to happen?

the early Earth must have been so hot it was like a liquid and heavier things sank to the middle

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

The region around the Earth where charged particles are trapped and spiral around is called:

the magnetosphere

The U.S. has plans to build a 30-meter telescope, while the Europeans are thinking about 39-meter telescope. What technological innovation allows astronomers to be thinking about telescopes with that large an aperture?

the mirror in these telescopes will be constructed from many smaller mirrors which will work together

The celestial sphere turns once around each day because

the planet on which we live is rotating

In Ptolemy's system the planets orbit the Earth and not the Sun. How did the 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

The Viking spacecraft were designed (in part) to search for life on Mars. Which of the following statements about the results of these experiments is true?

Viking found that the surface of Mars in the two places it searched did not have any life or even life's building blocks

What relatively recent event shows that impacts continue to happen in our solar system even today?

a comet (which broke into more than 20 pieces) hit the planet Jupiter in 1994

In a radio telescope, the role that the mirror plays in visible-light telescopes is played by:

a large metal dish 'antenna'

A graduate student is trying to follow the weather on Jupiter for her PhD thesis. To see the big weather patterns in the upper atmosphere of the planet, she needs to have excellent resolution. What type of telescope would be best for her to use?

a large reflector located in orbit above the Earth's atmosphere

In a bad late-night science fiction film, a villain is using a large collection of rare radioactive atoms as energy for a weapon to threaten the good guys. The atoms have a half-life of 1 hour. The villain has 4 kilograms of the radioactive material now, and he needs a minimum of 1 kg. for his weapon to work. After how much time will the weapon no longer be a threat?

a little after 2 hours

We have two waves of light, A and B. Wave A has a higher frequency than wave B. Then wave B must have:

a longer wavelength

What happens as an electron falls from a higher level to a lower level in an atom?

a photon is given off

What is the Van Allen belt?

a region of trapped charged particles in the Earth's magnetosphere

Which of the following places is most likely NOT to be differentiated?

a small asteroid

To break up light into the component colors that it contains, astronomers use a device called:

a spectrometer

An astronomer observes two ordinary stars. The first one turns out to be twice as hot as the second. This means that the first one radiates:

about 16 times the energy of the second

Describe prime focus in telescope focal arranements

light is detected where it comes to a focus after reflecting from the primary mirror

Sometimes, when the Moon is a thin crescent, you can still dimly make out the full disk of our satellite. What is the reason for this?

light reflecting from the Earth onto the Moon

About 75% of the surface of Venus consists of

lowland lava plains

An astronomer discovers a new star and wants to measure its temperature. She would typically do this by:

making a blackbody curve and finding the wavelength of the peak (maximum)

The largest part of the Earth is its

mantle

An important way that scientists have been able to study the interior of the Earth is by:

measuring seismic waves transmitted through the earth

which planet is closest to the sun?

mercury

The most likely models of the planet Mercury indicate that more than half the planet may be composed of

metals

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

What phase of the Moon must it be to have a solar eclipse?

new moon

On which of the planets (other than Earth) could a human being step out of a spacecraft and survive without any protective gear (special suit, oxygen tanks, etc)?

none duh

Newton showed that to change the direction in which an object is moving, one needs to apply:

A force

We now know that the orbit of a stable planet around a star like the Sun is always in the shape of:

An ellipse

How much would you weigh if you were twice the distance from the center of the earth

At the Earth's surface the force of gravity is inversely proportional to the square of your distance to Earth's center of mass. So, if you were twice as far from the Earth's center as you are now, you'd weight one divided by two squared, or one quarter, as much

Not all wavelengths of electromagnetic radiation can penetrate the Earth's atmosphere. Of the following types of waves that come from space, which one are you likely to be able to detect most easily from our planet's surface: a. x-rays b. gamma rays c. infrared waves d. ultraviolet waves e. radio waves of the wavelength that carry FM broadcasts

E. radio waves of the wavelength that carry FM broadcasts

Why are there no smaller craters on the surface of Venus, only bigger ones?

In Venus' thick atmosphere all smaller chunks of material burn up before they can reach the surface

The Earth is closest to the Sun in which month of the year?

January

Why is it so much easier to determine the length of the day on Mars than on Venus?

Mars' atmosphere is generally pretty clear (so the surface is visible) while Venus is always cloudy

The star that is currently closest to the North Celestial Pole is

Polaris

Recently, the media, always trying to make things sound sensational, have started to call totally eclipsed moon (the blood moon.) Why does the Moon look reddish to us when there is a total lunar eclipse?

The Earth's atmosphere bends different colors of light to a different degree. During a total lunar eclipse, the red light of the Sun, filtering through the Earth*s atmosphere colors the Moon red

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

Why does Mars have an overall reddish color when we see its surface from afar?

The material of Mars' surface contains a lot of iron oxide, the same chemistry that makes rusting metals look reddish

A friend of yours (who has not had the benefit of an astronomy course) tells you about a report he has read in a tabloid newspaper. They claim that on the dark side of the Moon, which is never in sunlight, there is a secret base of aliens who cannot stand light, and who send UFO's to Earth under the cover of darkness. Ignoring the UFO claim for a moment, what is the scientific error in this story?

all sides of the Moon are illuminated by sunlight in the course of a month; there is no dark side

We believe the maria on the Earth's Moon are

ancient impact craters in which lava beds welled up from inside the Moon

The mountains on the Moon

are the result of giant impacts during the Moon's long history of being hit

An eccentric billionaire wants to build a mansion in a location on Earth where the effect of the seasons is the least pronounced -- where summer and winter are not that different. Where should his personal astronomer advise him to build?

at the equator

Why are the largest craters we find on the Moon and Mercury so much larger than the largest craters we find on the Earth?

because the largest craters were made early in each world's history, and geologic activity has erased all traces of this early period on the Earth's surface

Why do different types of atoms (elements) give off or absorb different spectral lines?

because the spacing of the energy levels is different in different atoms

How did Eratosthenes measure the size of the Earth?

by measuring the height of the Sun in the sky on the same day in two cities at different latitudes

The same gas makes up most of the atmosphere of Mars and Venus. This gas is

carbon dioxide

According to Kepler's third law, there is a relationship between the time a planet takes to revolve around the Sun and its

distance from the sun

One piece of evidence that can help astronomers sort out how the planets in our solar system formed is

finding circumstellar disks of material around nearby stars

What phase of the Moon must it be to have a lunar eclipse?

full moon

You are alone in a large, completely dark auditorium on Earth. What kind of telescope should I use from the other side of the auditorium to detect the electromagnetic radiation emitted by your body?

infra-red

When an atom has lost one or more electrons, it is said to be:

ionized

Astronomers believe that Mars formed with a much thicker atmosphere than it has today. Where did this atmosphere go?

it escaped into space (and some later froze out as Mars got cold)

The inner planets are made mostly of rock and metal because:

it was so hot where the inner planets formed that the lighter materials evaporated

The major source of information about bodies in the universe (outside of Earth) is through

their light

What makes astronomers think that impact rates for the Moon must have been higher earlier than 3.8 billion years ago?

there are ten times more craters on the older highlands than the younger maria

What is one important way in which both the Moon and Mercury are different from Earth?

they do not have an atmosphere

Mars rovers (such as Opportunity and Curiosity) have identified evidence that their landing sites were once under water. Which of the following is among the kinds of evidence they have identified?

they found rock formations that show the area was under water and also minerals that only form in water

What is one way that we humans are currently making the atmosphere of the Earth more like that of Venus?

we are adding carbon dioxide and other greenhouse gases to the atmosphere, which is leading to global warming

What is the most important reason that astronomers have learned more about our planetary system in the last 30-40 years than all of history before then

we have been able to send spacecraft to gather information about planets and moons up close

Which of the following types of telescopes can be used ONLY above the Earth's atmosphere?

x-ray telescope

Which planet in the solar system has not been examined by spacecraft instruments that have either flown by or orbited them?

you can't fool me, spacecraft have visited all the planets in our solar system

The point in the sky directly above your head at any given time is called the

zenith