question

A long thin cloud that stretched from directly overhead to the western horizon would have an angular size of

answer

90 degrees

question

When a thin crescent of the Moon is visible just before sunrise, the Moon is in its

answer

waning phase

question

f the Moon's orbit around Earth were a little larger, solar eclipses would be

answer

more likely to be annular

question

According to "The Zodiac" Figure shown above, in June we would see the Sun in the direction of the constellation(s)...

answer

Gemini

question

In the Figure below (Figure 0.20A - Parallax), a smaller Earth would result in

answer

a smaller parallax angle.

question

How, and by roughly how much, would the length of the solar day change if Earth's rotation were suddenly to reverse direction?

answer

A solar day would be approximately 8 minutes shorter than the current one.

question

If you watch Polaris all night, what does it do?

answer

Not much! It just sits there.

question

When is the Earth closest to the Sun?

answer

In the winter in the northern hemisphere.

question

What causes Earth's seasons?

answer

23.5° tilt of Earth's rotational axis

question

The angle of parallax increases as

answer

the baseline gets larger.

question

Why don't we have solar and lunar eclipses every month?

answer

ecause the Moon's orbit around Earth is tilted by about 5° out of the ecliptic.

question

he average distance from the Earth to the Sun, 149,600,000 km, can be written in scientific notation as

answer

1.496 × 108 km.

question

If there are about 6000 stars in the entire sky that can be seen by the unaided human eye, about how many stars would be seen at a particular instant on a given dark night from a single location with an uninterrupted distant horizon?

answer

3000

question

Are the constellations seasonal?

answer

Yes. On a summer night many of the constellations you can see are different from the constellations you can see on a winter night. But there are some constellations you can see all year long.

question

At what time of the year in the northern hemisphere will your shadow in sunlight at midday be shortest?

answer

first day of summer, about June 21

question

How long does it take light to travel a distance of one light year?

answer

One year or about π×107 seconds.

question

What is the unit that we use to measure distances in the solar system?

answer

The astronomical unit or AU is very convenient.

question

The most southern location on Earth where the Sun can be seen directly overhead at noon is called

answer

the Tropic of Capricorn

question

How long would a radar signal take to complete a round trip between Earth to Mars and back to Earth when the two planets are 0.7 AU apart

answer

about 11.6 minutes

question

Mars, Jupiter, and Saturn show retrograde motion because

answer

Earth moves faster in its orbit.

question

Epicycles were used in Ptolemy's model to explain

answer

why retrograde motion occurred.

question

Copernicus' important contribution to astronomy was

answer

proposing a simpler model for the motions of planets in the solar system.

question

Which of Galileo's initial observations was most challenging to established geocentric beliefs?

answer

moons of Jupiter

question

Newton's law of gravity states that the force between two objects

answer

increases with mass.

question

The word planet is derived from a Greek term meaning

answer

wanderer

question

In the geocentric model of the solar system developed by Ptolemy, the planets move

answer

in circular epicycles while the centers of the epicycles move in circular orbits around the Earth.

question

he major contribution of Tycho Brahe to the development of modern astronomy was

answer

measuring planetary positions very accurately.

question

epler's second law states that a planet moves fastest when it

answer

is closest to the Sun.

question

to which point in a planetary orbit does the word perihelion refer?

answer

point closest to the Sun

question

hich of the following sentences correctly states the significance of Galileo's observation that Jupiter has satellites (moons)?

answer

The observation showed that bodies can orbit an object other than the Earth.

question

Suppose that a planet of the same mass as the Earth were orbiting the Sun at a distance of 10 AU. The gravitational force on this planet due to the Sun would be

answer

1/100 of the gravitational force the Sun exerts on the Earth.

question

stronomers analyze starlight to determine a star's

answer

motion, temp, composition, all of the above

question

What is the wavelength of a 98-MHz ("FM 98") radio signal?

answer

3.1 m

question

Rigel appears as a bright bluish star, whereas Betelgeuse appears as a bright reddish star. Rigel is

answer

hotter than Betelgeuse.

question

the light from a distant star is approaching you, you will observe

answer

its spectral lines are shorter in wavelength.

question

he wavelengths of emission lines produced by an element

answer

are identical to its absorption lines.

question

What types of electromagnetic radiation from space will reach the surface of Earth without being significantly absorbed by the Earth's atmosphere?

answer

visible light and radio waves

question

For lecture on "Waves", a sound wave can travel through ________.

answer

molten rock, solid rocks

question

How many times lower would the intensity of light from a given star become if the star is 2 times farther away?

answer

4 times

question

visible wavelengths of electromagnetic radiation have a range of wavelengths of

answer

400 nm to 700 nm.

question

forms of light have what property in common? (Light in this case refers to the whole spectrum, not just the visible range.

answer

All forms of light are electromagnetic radiation.

question

What is the one fundamental difference between X rays and radio waves?

answer

the wavelengths of X rays and radio waves are very different.

question

ieces of metal are heated by varying amounts in a flame. The hottest of the pieces will be the one that shows most prominently which color?

answer

blue

question

What changes would you expect to see in the resulting spectrum of emitted light from a piece of metal when it is heated slowly in an intense flame from 500 K to 1500 K?

answer

he intensity of radiation would increase greatly, and the color would change from red through white to blue.

question

An ideal blackbody in physics and astronomy is an object that

answer

absorbs and emits electromagnetic radiation at all wavelengths.

question

According to the Doppler effect

answer

the wavelength of light is shifted to a shorter wavelength if the source of light is moving nearer to the observer.

question

The Doppler effect is the change in the wavelength of light caused by the source

answer

moving with respect to the observer.

question

he dark absorption lines in the solar spectrum are caused by

answer

a cooler layer of gas overlying the hot solar surface, which contains many elements, including hydrogen, helium, magnesium, calcium, and iron.

question

Atoms in a low-density, hot gas (e.g., in a fluorescent lamp or a neon tube) emit a spectrum that is

answer

a series of specific colors unique to the type of atom in the tube but fixed in position when the gas temperature changes.

question

The main reason that most professional research telescopes are reflectors is that

answer

mirrors produce sharper images than lenses do since there is no chromatic aberration.

question

he PRIMARY reason professional observatories are built on the highest mountain tops is to

answer

reduce atmospheric blurring

question

the Spitzer Space Telescope is stationed far from Earth because

answer

This infrared telescope actually does not orbit the Earth, but follows our planet around the Sun, reducing the heat interference from Earth

question

The best way to study young stars hidden behind interstellar dust clouds would be to use

answer

infrared light

question

An FSU student is observing the phases of Venus with his 16 inch reflector telescope, and a UF student is doing the same with a 8 inch reflector telescope. How much more light gathering power does the FSU telescope have?

answer

4 times more

question

again, an FSU student is observing the phases of Venus with his 16 inch reflector telescope, and a UF student is doing the same with an 8 inch reflector telescope. How much "more" resolving power (i.e. angular resolution) does the FSU telescope have?

answer

Twice as much.

question

Seeing in astronomy is a measurement of

answer

the image quality due to air stability.

question

Resolution is improved by using

answer

larger telescopes and shorter wavelengths.

question

an advantage of CCDs over photographic film is

answer

they don't require chemical development,digital data is easily store and transmitted, CCDs are more light sensitive than film, CCD images can be developed faster. All of the above are true.

question

Radio dishes are large in order to

answer

improve angular resolution.

question

adaptive optics refers to

answer

reducing atmospheric blurring using computer control.

question

Radio telescopes are useful because

answer

observations can be made day and night, radio waves are not blocked by interstellar dust, we can see objects that don't emit visible light, they can be linked to form interferometers. Correct: All of the above are true.

question

The Hubble Space Telescope (HST) offers sharper images than ground telescopes primarily because

answer

HST orbits above the atmosphere.

question

the light-gathering power of a telescope depends directly on the

answer

area of its primary mirror or lens.

question

What is the main reason for placing astronomical telescopes and detectors on satellites?

answer

to get above the absorption in the Earth's atmosphere

question

The major difference(s) between the terrestrial and jovian planets involve(s)

answer

mass and density.

question

The asteroid belt is evidence of

answer

ancient material from the formation of the solar system.

question

Pluto seems to be more similar to

answer

the moons of jovian planets.

question

What causes a meteor shower?

answer

Earth runs into the debris of an old comet littering its orbit.

question

Any theory of the origin of the solar system must explain all of these EXCEPT

answer

the direction that planets orbit the Sun is opposite to the Sun's spin.

question

The condensation sequence theory explains why

answer

terrestrial planets are different from jovian planets.

question

xtrasolar planets the size of Earth have NOT been seen yet with current techniques because

answer

large planets orbiting near to their stars are more easily detected.

question

s a rotating gas cloud contracts, it spins faster.

answer

True

question

In the solar nebular theory, the dusty disk condensing around the Sun's equator became the ecliptic plane in which the planets then formed.

answer

true

question

Due to their great masses, all four Jovian worlds are much denser than the earth.

answer

false

question

the temperature in the solar nebula at the location now at the center of the asteroid belt is

answer

400k

question

Strong evidence for the existence of planetary systems in the process of formation around other stars comes from

answer

photographs and infrared observations of disks of dust.

question

The Moon's internal structure is similar to Earth's, but the Moon lacks

answer

a hydrosphere. a magnetosphere. an atmosphere. Correct: It lacks all of the above

question

The principal greenhouse gases in our present atmosphere are

answer

water vapor and carbon dioxide.

question

At what lunar phase would the variation between high and low tides be greatest?

answer

both new and full moon

question

What is true of the Moon's orbital and rotational periods?

answer

They are equal.

question

he magnetic field of the Earth probably arises from what process or condition?

answer

A dynamo effect due to the motion of the electrically conducting molten iron core.

question

Without the greenhouse effect operating in our atmosphere,

answer

Earth would have an average temperature of -23 degrees Celsius.

question

The Moon's near side always faces Earth due to

answer

Earth's tidal force.

question

What are the two most abundant gases in the Earth's atmosphere

answer

Nitrogen and Oxygen

question

Why did Earth's earliest atmosphere, composed primarily of hydrogen and helium, not last long?

answer

Hydrogen and helium are light gases, and they soon escaped into space.

question

What is the distribution of maria on the Moon's surface?

answer

Maria are largely confined to the hemisphere facing Earth; there is only one small mare on the distant side.

question

How do the atmospheres of the Moon and Mercury compare?

answer

Neither body has a permanent atmosphere.

question

Mercury has extreme high and low temperatures between night and day because

answer

it has no atmosphere to moderate temperatures over the globe.

question

hich of the following inner solar system bodies has the densest atmosphere?

answer

venus

question

he greenhouse effect on Venus is due to carbon dioxide in its atmosphere.

answer

carbon dioxide

question

enus' surface shows all of the following EXCEPT

answer

many impact craters of all sizes.

question

Venus and Mars probably evolved differently from Earth because

answer

they orbit at different distances from the Sun.

question

How does Mercury's rotation rate relate to its orbit around the Sun?

answer

Its rotation rate is 2× as long as its year, due to tidal resonances.

question

Venus' rotation once about its axis

answer

takes longer than its orbit around the Sun.

question

The chief gas in the martian atmosphere is

answer

carbon dioxide.

question

Why are Mars's seasons more extreme than those of the Earth?

answer

weather is driven by evaporation from the polar ice in its summer. orbit is more eccentric than our almost circular one. seas dried up long ago. axial tilt is slightly more than our 23.5 degrees. Correct: All of the above contribute to the huge barometric changes that Mars experiences.

question

Why doesn't Venus have a magnetic field?

answer

Its extremely slow rotation doesn't produce a significant dynamo effect.

question

The craters on the Moon and on Mercury surfaces are due to

answer

impacts from meteorites and asteroids.

question

The surface temperature on Venus is

answer

much higher than that on the surface of the Earth.

question

Mercury can be seen easily from the Earth only

answer

when Mercury is near the Sun, just after sunset or just before sunrise.

question

the best images of the overall topology of Venus have been produced by

answer

reflection of microwave and short radio wave radiation from the surface by an orbiting spacecraft.

question

The most likely explanation for the retrograde rotation (rotation in a direction opposite that of most other planets) of Venus is the

answer

impact of a massive object on it early in its history

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