Astronomy Ch.2

We describe a position on Earth's surface by stating its

latitude and longitude

When are eclipse seasons?

when the nodes of the Moon's orbit are nearly aligned with the Sun

Which of the following never goes in retrograde motion?

the Sun

What is the ecliptic?

the Sun's apparent path along the celestial sphere

The precessi on of the Moon's nodes means that

the eclipse seasons occur less than 6 months apart

Orion is visible on winter evenings but not summer evenings because of

the location of earth in its orbit

If the Moon rises around 3am, its phase must be

waning crescent

At approximately what time would a full Moon be on your meridian?

Midnight

Which of the following statements about constellations is false?

Most constellations will be unrecognizable hundreds of years from now

When we look into the band of light in our sky that we call the Milky Way, can we see distant galaxies? Why or why not?

No, because the stars, gas, and dust of the Milky Way block us from seeing them

How many arcseconds are in 1°?

3,600

How many stars can you see with your naked eye on a clear, moonless night from a dark location?

A few thousand

Which of the following statements is true?

A). Both the Northern and Southern Hemispheres receive the same amount of sunlight on the equinoxes and C). The Northern hemisphere receives the most direct sunlight on the summer solstice

Why do we have seasons on Earth?

As Earth goes around the Sun and Earth's axis remains pointed toward Polaris, the Northern and Southern hemispheres alternately receive more and less direct sunlight.

What causes the apparent retrograde motion of the planets?

As earth passes another planet, the other planet appears to move backwards with respect to the background stars, but the planets motion does not really change

Why do we see essentially the same face of the Moon at all times?

Because the Moon's rational and orbital periods are equal

In which direction does a quarter Moon rise?

East

If the Moon is setting at 6am, the phase of the moon must be

Full

If, from the point of view of Earth-bound observers , the Moon is in the new Moon phase on a particular day, what phase is the Earth as seen from the Moon?

Full Earth

What makes the North Star, Polaris, special?

It appears very near the north celestial pole.

Which of the following statements about lunar phases is true?

It is possible to have two full moons during January, but not during February

Which of the following statements about the celestial equator is true at all altitudes?

It represents an extension of Earth's equator onto the celestial sphere

At approximately what time would be a first quarter Moon rise?

Noon

You are standing on Earth's equator. Which way is Polaris, the North Star?

On the Northern Horizon

What effects would be most significant if the Moon's orbital plane were exactly the same as the ecliptic plane?

Solar eclipses would be much more frequent

Which of the following statements about the celestial sphere is not true?

The "celestial sphere" is just another name for our universe

What is the saros cycle?

The 18-year cycle over which the pattern of eclipses repeats

Which of the following statements about the Moon is true?

The Moon's distance from Earth varies during its orbit

Why is it summer in the Northern Hemisphere when it is winter in the Southern Hemisphere?

The Northern Hemisphere is tilted toward the sun and receives more direct sunlight

By locating the north celestial pole (NCP) in the sky, how can you determine your latitude?

The altitude of the NCP is the same as your latitude

Which of the following statements does not use the term angular size or angular distance correctly?

The angular distance between these two bright stars in the sky is about 2 meters

Which of the following statements about stellar parallax is true?

The closer a star is to us, the more parallax it exhibits

In addition to the conditions required for any solar eclipse, what must also be true in order for you to observe a total solar eclipse?

The moon's umbra must touch the area where you are located

All of the following statements are true. Which one explains the reason why there is not a solar eclipse at every New Moon?

The orbital plane of the Moon is tilted by about 5 degrees to the ecliptic plane

What conditions are required for a lunar eclipse?

The phase of the Moon must be full, and the nodes of the Moon's orbit must be nearly aligned with Earth and the Sun.

What conditions are required for a solar eclipse?

The phase of the Moon must be new, and the nodes of the Moon's orbit must be nearly aligned with Earth and the Sun.

What happens during the apparent retrograde motion of a planet?

The planet appears to move eastward with respect to the stars over a period of many nights

Which of the following statements about parallax is not true?

The technique of stellar parallax was used by Hubble to determine that the Andromeda Galaxy (M 31) is about 2 million light-years away

Which of the following statements about circumpolar stars is true at all latitudes?

They always remain above your horizon

Why were ancient peoples unable to detect stellar parallax?

They did not have the ability to measure very small angles

If the Moon is setting at noon, the phases of the Moon must be

Third Quarter

If the Moon is rising at midnight, the phase of the moon must be

Third quarter

Which of the following correctly describes the meridian in your sky?

a half-circle extending form your horizon due north, through your zenith, to your horizon due south

Suppose you live on the Moon. How long is a day (i.e., from sunrise to sunrise)?

a lunar month

Which of the following best describes the modern definition of a constellation?

a region of the celestial sphere

What is a circumpolar star?

a star that always remains above your horizon

If the Moon is relatively far from Earth, so that its umbra does not reach Earth, someone directly behind the umbra will see

an annular eclipse

If it is midnight in New York, it is

daytime in Sydney, Australia.

Which of the following is not a phase of the Moon?

half moon

We can't detect stellar parallax with naked-eye observations. Which of the following would make parallax easier to observe?

increasing the sizes of Earth's orbit

If part of the full Moon passes through Earth's umbra, we will see a(n)

partial lunar eclipse

Ancient people who knew the Saros cycle could

predict when an eclipse would happen, but not necessarily what type and where it would be visible.

A Shen light (or earthshine) is

sunlight reflected by Earth that illuminates the "dark" portion of the Moon

When someone on Earth observes the Moon in the first-quarter phase, someone on the Moon facing Earth observes Earth in the

third-quarter Earth phase