Brainscape's Knowledge GenomeTM

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


See full index

Astronomy Final > Astronomy Final > Flashcards

Astronomy Final Flashcards

1
Q

What are the standard units for luminosity?

A

Watts

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

Purpose of adaptive optics

A

Eliminate distorting effects of atmospheric turbulence for telescopes on the ground

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

How does the sun generate energy?

A

Nuclear Fusion

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

What observations characterize solar maximum?

A

we see many sunspots on the sun’s surface

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

When white light passes through a cool cloud of gas, we see

A

an absorption line spectrum

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

How are wavelength, frequency, and energy related for photons of light?

A

Longer wavelength means lower frequency and lower energy

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

HR Diagram: Cool and Dim

A

Lower right

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

Overall fusion reaction by which the sun produces energy

A

4 H -> He + Energy

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

Thermal Radiation:

A

radiation that depends only on the emitting objects temperature.

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

Layers of the sun from center outward

A

Core, radiation zone, convection zone, photosphere, chromosphere, corona

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

What is true of images captured in X-Ray telescopes?

A

Always displayed in false color

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

What is the closest temperature to the CORE of the sun?

A

10 million K

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

What is NOT an advantage of the Hubble Telescope over ground-based telescopes?

A

It is closer to the stars

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

Luminosity

A

Total amount of light that the star radiates each second

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

Gravitational Equilibrium

A

balance between the outward push of pressure and the inward pull of gravity.

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

On the main sequence, stars obtain their energy by

A

converting hydrogen to helium

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

HR Diagram: Largest Radii

A

Upper right

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

Lowest energy- highest energy:

Different categories of electromagnetic radiation

A

radio, infrared, visible light, ultraviolet, x-ray, gamma

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

Cluster ages can be determines from

A

main-sequence turnoff

20
Q

Size of the neutron star

A

City

21
Q

What temperature can helium fusion occur?

A

100 million K

22
Q

What is the closest in mass to a white dwarf?

A

the sun

23
Q

10-solar mass main-sequence star will produce a:

A

neutron star

24
Q

Planetary Nebula

A

expanding shell of gas that is no longer gravitationally held tot he remnant of a low-mass star

25
Q

What’s the upper limit to the mass of a white dwarf?

A

1.4 solar masses

26
Q

How is time affected by gravity?

A

Time runs slower in places where gravity is stronger

27
Q

Stages of life for a low-mass star:

A

Protostar, main-sequence, red giant, white dwarf

28
Q

How many helium nuclei fuse together when making carbon?

A

3

29
Q

How does gravity of an object affect light?

A

Light from a massive object will be redshifted

30
Q

Pulsar:

A

an object that emits flashes of light several times per second or more, with near perfect regularity

31
Q

What is the closest in size to a white dwarf?

A

Earth

32
Q

White dwarfs are called so because

A

they are both very hot and very small

33
Q

What happens after a helium flash?

A

the core quickly heats up and expands

34
Q

How far is the sun from the center of the galaxy?

A

28,000 light-years

35
Q

How did Edwin Hubble measure the distance to the Andromeda Galaxy?

A

applied the period-luminocity relation to cepheid variables

36
Q

Diameter of the Milky way?

A

100,000 light-years

37
Q

Why do we cal dark matter “dark”

A

Emits no or very little radiation of any wavelength

38
Q

Dark Energy

A

the agent causing the universal expansion to accelerate

39
Q

Methods for determining distance: nearest to farthest

A

parallax, main-sequence fitting, cepheid variables, Tully-Fisher, Hubble’s Law

40
Q

Quasar:

A

Extremely bright center of a distant galaxy, thought to be powered by a massive black hole.

41
Q

Spectral Sequence in order of decreasing temperature

A

OBAFGKM

42
Q

Hubble’s Law

A

Recession velocity of a galaxy is directly proportional to its distance from us

43
Q

Most large galaxies are:

A

Spiral or lenticular

44
Q

Galaxy type most commonly found in large clusters

A

Ellipticals

45
Q

What happens when a star exhausts its core hydrogen supply?

A

Its core contracts, but its outer layers expand and the star becomes bigger and brighter

46
Q

How long does it take the sun to orbit the Milky Way Galaxy?

A

230 million years

Astronomy Final (1 decks)

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