Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Astronomy > Science and The Universe > Flashcards

Science and The Universe Flashcards

1
Q

What is our physical place in the universe?

A

Earth is part of the solar system, which is the Milky Way Galaxy, which
is a member of the Local Group of galaxies in the Local Supercluster.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How did we come to be?

A

The mater in our bodies came from the Big Bang, which produced hydrogen and helium.
All other elements were constructed from H and He in stars and then recycled into new star systems, including our solar system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How can we know what the universe was like in the past?

A

When we look to great distances, we are seeing
events that happened long ago because light travels at a fnite speed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Can we see the entire universe?

A

No. The observable porton of the universe is about 14-15 billion
light-years in radius because the universe is about 14-15 billion years old

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Light travels at a fnite speed thus … ?

A

Thus, we see objects as they were in the past: The farther away we
look in distance, the further back we look in time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Light year

A

The distance light can travel in one year. About 10 trillion km (6 trillion miles).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How big is Earth compared to our solar system?

A

The distances between planets are huge compared to their sizes
—on a scale of 1-to-10 billion, Earth is the size of a ball point and the Sun is 15 meters away

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How far away are the stars?

A

On a scale of 1-to-10 the stars are thousands of km away.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How big is the milky way galaxy?

A

The Milky Way is one of about 100 billion galaxies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How big is the universe?

A

10^11 stars/galaxy x 10^11 galaxies = 10^22 stars. It would take more than 3,000 years to
count the stars in the Milky Way Galaxy at a rate of one per second, and they are spread across 100,000 light-years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many billion light years in radius is the observable universe

A

14 billion light years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How many galaxies does the observable universe contain?

A

100 billion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do our lifetmes compare to the age of the universe?

A

On a cosmic calendar that compresses the history of the Universe into one year, human civilizaton is just a few seconds old, and a human lifetme is a fracton of a second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Distance of Earth moving in our solar system?

A

Earth orbits the Sun (revolves) once every year at an average distance of 1 AU ≈ 150 million km. Earth’s axis is tlted by 23.5º (pointng to Polaris).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Does Earth rotate in the same or a different direction then it’s orbit

A

Earth rotates in the same directon it orbits, counter- clockwise as viewed from above the North Pole.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is our the stars in our solar system are moving in the Milky Way galaxy?

A

Stars in the Local Neighborhood move randomly relatve to one another but the stars are so far away that we cannot easily notce their moton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How is our solar system moving in the Milky Way galaxy? (focus on the sun)

A

Our Sun moves randomly relatve to the other stars in the local Solar neighborhood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How fast does the sun move

A

typical relative speeds of more than 70,000 km/hr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How long does it take for the sun to orbit the milky way galaxy

A

Our Sun orbits the center of the Milky Way in about 230 million years.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do galaxies move within the universe?

A

All galaxies beyond the Local Group are moving away from us with expansion of the Universe: the more distant they are, the faster they’re moving

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Hubble discovered that:

A

All galaxies outside our Local Group are moving away from us.
The more distant the galaxy, the faster it is racing away.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What can we conclude from Hubble’s discovery that all the galaxies are moving away from us?

A

Our galaxy is expanding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How many stars can we see with out naked eye?

A

We can see over 2,000 stars and the Milky Way with our naked eyes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

each positon on the sky belongs to one of (how many) constellatons?

A

88

25
Q

How can we specify the position of an object in the local sky?

A

We can specify the positon of an object in
the local sky by its alttude above the horizon and its directon along the horizon

26
Q

Constellation

A

a constellaton is a region of the sky

27
Q

Can we say that the stars in the same constellaton are nearby?

A

no

28
Q

Why is it hard to notice the motion of the stars?

A

Because they are so far away

29
Q

Why do stars rise and set?

A

Because of Earth’s rotaton. Stars near the north celestal pole are circumpolar and
never set. All other stars (and Sun, Moon, planets) rise in east and set in west.
Earth rotates west to east, so stars appear to circle from east to west

30
Q

What is a circumpolar star?

A

Stars near the north (south) celestal poles are circumpolar and never set. All other
stars (and Sun, Moon, planets) rise in east and set in west. Circumpolar stars rotate in counterclockwise directon
around North celestal pole in the Northern Hemisphere.

31
Q

What is the ecliptic plane?

A

Ecliptic is Sun’s apparent path through the celestial sphere.

32
Q

The sky varies as Earth orbits the Sun

A

As the Earth orbits the Sun, the Sun appears to move eastward along the ecliptic.
At midnight, the stars on our meridian are opposite the Sun in the sky.

33
Q

Why do the constellatons we see depend on lattude and tme of year?

A

The constellatons we can see depend
on lattude because your positon on Earth determines which constellatons remain below the horizon and hidden
by Earth. They depend on tme of year because Earth’s orbit changes the apparent locaton of the Sun among
the stars. We can’t see the stars during the day!

34
Q

Altitude:

A

An object’s altitude (above horizon) and direction (along horizon) specifies its location in your
local sky

35
Q

Zenith:

A

The point directly overhead

36
Q

Horizon:

A

All points 90° away from zenith

37
Q

Meridian:

A

Line passing through zenith and connecting N and S points on horizon

38
Q

Stars near the _________ pole are circumpolar and never set.

A

north celestial

39
Q

Polaris Alttude and our locaton on Earth.

A

For an observer Polaris alttude will be the same as a person’s lattude on Earth.

40
Q

What makes the North Star, Polaris, special?

A

Some stars travel a great distance over the course of the night. Polaris is different. Because it’s so close to the celestial pole, it traces out a very small circle over 24 hours. So Polaris always stays in roughly the same place in the sky, and therefore it’s a reliable way to find the direction of north

41
Q

Astronomy def

A

the study of the objects that lie beyond our planet Earth and the processes by which these objects interact with one another.

42
Q

1st step in the method of learning about Astronomy

A

Observing things over time

43
Q

. The most straightforward approach to such testing in science is to ______________.

A

perform an experiment

44
Q

What do astronomers do?

A

sift through and organize the evidence to test various hypotheses about what actually happened.

45
Q

scientific laws

A

the “rules” of the game that nature plays.

46
Q

A reason why astronomers strive to build telescopes that collect the faint light in the universe

A

On average, fainter objects are farther away and can, therefore, tell us about periods of time even deeper in the past.

47
Q

Our nearest astronomical neighbor is ______

A

the moon

48
Q

If we travel around the sun in one year how fast do we travel in an hour?

A

110,000 kilometers per hour.

49
Q

Why are we able to see planets?

A

They reflect the light of the sun?

50
Q

How do stars produce vast amounts of energy

A

by nuclear reactions deep within.

51
Q

What makes stars considered “triplets or doubles”

A

If they revolve around each other

52
Q

Magellanic Clouds

A

Two dwarf galaxies

53
Q

Andromeda galaxy

A

The nearest galaxy to us

54
Q

Our “address” in the universe

A

you, Earth, solar system, Milky Way, Local Group, Local Supercluster

55
Q

Suppose we look at a photograph of many galaxies. Assuming that all galaxies formed at about the same time, which galaxy in the picture is the youngest? The one farther away or closer?

A

Farther away

56
Q

What’s larger, a light year or the size of a typical galaxy

A

the size of a typical galaxy

57
Q

What is the meaning of the word cosmos?

A

the sum total of all matter and energy, that is, everything within and between all galaxies

58
Q

Suppose we imagine the Sun to be about the size of a grapefruit. How big an area would the orbits of the eight planets of the solar system cover?

A

the size of a typical campus

Astronomy (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions