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