Astronomy 1

How many zodiac constellations are circumpolar (as seen from WI)?

none

The moon and stars shine primarily because

they reflect light from the sun

Mars reached opposition in early November, 2005. Mars is at opposition every 2.2 years but Pluto is at opposition every 1.005 years. The reason Pluto's oppositions come more often is: (You need to figure it out, not look it up)

Mars has a year almost 2 Earth years, but Pluto takes much longer to orbit the sun.

Why do most backyard astronomers have reflecting telescopes instead of refracting telescopes?

Reflectors are lighter in weight and all colors focus in the same place

What galaxy can be seen without even binoculars (under the right conditions; in the northern hemisphere)?

Andromeda Galaxy

What do you call that round star chart thing where the top slides so you can set it for what constellations are up at a certain day and time?

planisphere

Which of these is one of the most easily visible (though a telescope) Messier objects?

The ring Nebula

To be able to use some light but not degrade your night vision (night vision: ability to see at low light levels), astronomers use

red light

Averted Vision" is used by backyard astronomers to see faint objects. "Averted vision" means to

look at a point near the object, instead of looking directly at the object

In the Northern hemisphere, "Polaris is always closer to the Northern horizon", but the one exception is if it is at the zenith. If Polaris is at your zenith (straight overhead), where are you on Earth? *

North Pole

If you travel to Canada from Eau Claire, how does the number of circumpolar ("never set") stars change? ***

it increases

The town of Cadot has a sign that says it is "halfway between the equator and the North pole". How high above the horizon is Polaris as seen from Cadot? ***

45�

When is the sun in your eyes when you drive west just before sunset on an East-west road? Hint: Looking down a road to the west, at most times of year the sun will set to the left or right behind houses and/or trees, *

near both of the equinoxes

If you travel south, how does the altitude (above the horizon) of Polaris change? **

it moves closer to the northern horizon

What is the declination of Mintaka (Delta Orionis), a star that is located on the celestial equator? (see figures 1-7, 1-8, 1-16 in "In Quest of the Universe"). ***

0�

At our latitude of 44�, stars with declination of 44� pass overhead. The sun never passes overhead, since its maximum declination is ___ (at summer solstice), (and its dec is _____ at the equinoxes). ***

23�, 0�

If you took a many-hour video of the northern sky from Eau Claire, you could see some stars move in circular patterns. All of these circles are centered near **

the North star, the North celestial pole, Polaris

The length of daylight is longest on __________________ and the sun rises farthest to the north on ________________. **

summer solstice, summer solstice

Winter is colder than summer" because of the tilt of Earth's axis away from the sun in winter. It comes down to two reasons. One reason is that the days are shorter (the nights are longer). What is the other reason? ***

the sun is lower in the sky, so the light is less intense

What could make a planet have very extreme seasons (a big difference between summer and winter)? **

a large axis tilt relative to its orbit

In January we can see Orion in the night sky, but not in June. If we went to the southern hemisphere, could we see Orion in June?

No, everyone on Earth sees the sun near Orion in June

If we could see the stars in the day, we could see the sun change its position compared to the stars. (And we could see the sun and stars rise and set together, caused by Earth's rotation). What causes the sun to "move across the stars"? *

the earth orbiting the sun

Would the constellations still have the same pattern if seen from Pluto? ***

Yes, because the stars are so far away compared to the distance to Pluto

At noon in mid-July, the sun is in the constellation Gemini. How long will it be before you could see Gemini high in the sky at midnight?

6 months

If the leftmost star in Orion's Belt sets at 6am today, about when will it set tomorrow?

4 minutes before 6am

When during the year does the sun set north of due West?

from the vernal equinox to the autumnal equinox

Once again, you wake up in a field at night and do not know where you are. You resolve to change your life so that this doesn't happen again. You find the North Star in the sky to your left and see the moon rising straight ahead of you. From this you know

you are in the northern hemisphere but do not know the latitude

If you are at a latitude of 35� north, where is Polaris in the sky?

at an altitude of 35� above the northern horizon

Why does the sun move along the ecliptic?

Earth is orbiting the sun

You are at Hobbs Observatory and the volunteer running the telescope asks "Should we point the telescope at M80?" You guess at what kind of object it is and say....

a star cluster

the seasons on Earth occur primarily because

the Earths axis is tilted with respect to the ecliptic plane

the :zenith" defines a direction

vertically above the observer

At noon in mid-July, the sun is in the constellation Gemini. How long will it be before you could see Gemini high in the sky at midnight?

6 months

Pluto is now defined to be

a dwarf planet

From the Earth's north pole

only half the celestial sphere can be seen on any clear night

You see Polaris 30 degrees above the horizon. At what latitude are you located?

30 degrees

In WI we can't see Canis Major in the evening in June and we call it a "winter constellation". can people in the southern hemisphere see Canis Major in the evening in June?

No, because of where the earth is in its orbit around the sun

The statement that "astronauts are weightless on the moon" is

false because the moon exerts a gravitational force on their bodies

Suppose 10 years from now you see a bright "star" in the East soon after sunset. You conclude that the "star

is not venus because venus can never been seen toward the East soon after sunset

If you lived at a moonbase on side of the moon facing earth

you could see stars move, but it takes them a month to rise and set

At what time of year does WI actually get the most intense sunlight?

summer solstice

In Galileo's lifetime, which was evidence against the heliocentric theory?

no stars had been found to have parallax, now they have

In which Apollo mission did all 3 astronauts die?

Apollo 1

When during the year does the sun set north of due west?

from vernal equinox to the autumnal equinox

right ascension is used to

give locations of stars on the celestial sphere

The observed changing positions of the stars during a night is the result of the

Earths rotation about its axis

The ocean tides experienced on Earth when the sun and moon are on opposite sides are

more pronounced than usual as the sun and moon work together

A new comet is discovered, with a semi-major axis of its orbit around the sun of 18 AU. How long does it take to orbit once around the sun?

square roof of 18 to the 3rd= 76 years

The constellations of the zodiac all

lie along the ecliptic

Suppose you are on a cruise in the Northern hemisphere, heading south toward the equator. As you travel, Polaris appears.........in the sky each night.

lower

You are still on the cruise heading south toward the equator. As you travel, the number of circumpolar stars that you observe each night

decreases

The date is Sept. 21st, and at noon you see the sun directly overhead

you are at the equator

The constellations of the zodiac are all located

along the ecliptic

How many zodiac constellations are circumpolar as seen from WI?

none

An observer at Earths equator will see the north celestial pole

on the northern horizon

Stars on the celestial equator

have a declination of zero

The time between Mars going through one loop of retrograde motion and it later going through another loop of retrograde motion is about

more than a year and less than 3 years

Kochab is a star that is always in the sky when viewed from Eau Claire. Given that information, where should you look to find Kochab?

in the northern sky

Proxima Centauri, in the Alpha Centauri star system, is the nearest star to us. For these planets and Proxima Centauri from closest to farthest from the sun...

venus, jupiter, pluto, proxima centauri

In WI, the vernal equinox occurs in March. Where on the Earth does the vernal equinox occur in December?

the vernal equinox always occurs on the same day, it is not related to where you are on Earth!

When we see the sun rise farthest north during the year it will set

farthest north

a light year is

the distance light travels in one year

How many stars in our solar system?

one

Why would the constellations still have the same pattern if seen from Pluto?

because the stars are so far away compared to the distance from Earth to Pluto

An early riser notices the moon setting at sunrise. What phase is it?

full

You see a waxing crescent moon near the eastern horizon. What time is it?

9 am

If you could see the stars during the day, this is what the sky would look like at noon on a given day. The sun is near the stars of the constellation Gemini. Near which constellation would you expect the sun to be located at sunset?

Gemini

If earth's moon orbited around earth in the direction opposite to earths rotation, it would

rise an hour earlier each day instead of an hour later

What time of year will a new moon reach its highest altitude above the horizon?

summer solstice

Which of the following statements constitutes a scientific hypothesis:

atoms are the smallest particles of matter that exist
-must be testable

What is the phase of the moon during a partial lunar eclipse?

full

Suppose that you live in WI an a friend calls from North Carolina. "Hi, its 10 am and there is a total lunar eclipse just starting," says your friend. You reply "Its only 9 am here" and realize

your friend must be wrong, since you can't see a lunar eclipse at 10 am

One night you see the moon straight ahead of you as you look south, and you notice it is near a bright star. If you go out and look south the next night at the same time, what will you see?

the star will be in almost the same place, and the moon will be more to the east