questions from last test Flashcards

1
Q

What is one source of light pollution?

A

Cities, street lights, the moon, nothern lights etc

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

Why can light pollution cause problems for astronomers?

A

Because their pupils are dilated and they cannot see the stars. affects night vision

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

What is a fireball?

A

A very bright meteor

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

Describe the appearence of aurorae

A

Light (often green) spiralling downwards

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

What is aurorae?

A

Charged particles from solar wind interacting with gas molecules in the atmosphere.

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

How do scientists use sunspots to determine the suns’s rotation period?

A

sunspots appear at certain points on the sun. Scientists track where they are to work out the rotational period.

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

Describe the appearance of sun spots with a H-alpha filter

A

They have a dork centre with a slightly lighter ring surrounding it.

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

Why would an astronomer use a H-alpha filter?

A

shows contrast

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

What are two pieces of evidence used to show extreme global warming on Venus?

A
  • Very thick/dense atmosphere traps heat

- Lots of Carbon dioxide

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

Which month of the year do shadow sticks give the shortest shadows at noon in the UK?

A

June

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

Which members of the solar system was the first to be discovered by using a photograph?

A

Pluto

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

Which members of the solar system was the first to be discovered by using a telescope?

A

Uranus

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

where to centaurs orbit the sun?

A

Jupiter and Neptune

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

I which part of the sky would an observer expect to observe a planet?

A

the Zodiacal Band

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

What does the angle of elevation of polaris above the horizon equal to?

A

The viewers latitude

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

What is a globular cluster?

A

A large group of old stars.

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

What can help you observe with your naked eyes?

A

A red torch or a relaxed eye.

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

What are 2 sources which can help you prepare for an observation?

A

Weather report, Planisphere

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

What is an open cluster?

A

A large group of young stars

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

meridian

A

imaginary line that runs from north to south through the zenith

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

why may an astronomer not be able to observe a certain constellation?

A

Due to the earths orbit of the sun. it may be in line with the sun or behind the earth making it not visible.

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

One major space mission:

A

Apollo, first humans on the moon, The moon is lifeless + contains very very old rock.

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

Galaxies in our local group:

A

Milky way, pisces dwarf, Aquarius Dwarf

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

how do we tell an active galaxy?

A

strong x-rays and radio emitters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How do astronomers observe neutron stars?

A

radio telescopes. Recieve radio waves in regualr bursts/pulses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a pulsar?

A

A pulsar is a rotating neutron star that emits a beam of electromagnetic radiation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are PHO’s?

A

thing that come relatively close to earth for example Comets, meteors and asteroids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Why are PHO’s regarded as hazardous?

A

because they could hit earth and cause devastation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is meant by: alpha, beta, gamme, delta etc?

A

Order of stars relative brightness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

At what distance is apparent magnitude equal to absolute magnitude?

A

10pc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is parallax?

A

looking at a star in june and then the same star in december means the star appears to move slightly, relative to the distant stars behind it, because we’re looking at it from a different angle. this effect is called parallax and can be used to work out the distance to the star with d = 1/ tan theta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

the theory that the moon was formed when a large body crashed into earth is backed up by:

A

similar isotopic abundances (oxygen) and lack of water and KREEP rich rocks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is Keplers second law/

A

An orbiting body will cover similar areas in the same time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what might an X-ray astronomer observe?

A

black holes, pulsars.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How were quasars discovered?

A

They are very strong radio sources furthermore highly reshifted emission line detected very distant galaxies. This fitted an optical observation of faint star like objects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the messier catalogue?

A

show what nebulae are visible and location of nearby galaxies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

how was CMB radiation discovered?

A

investigation of radio noise from all parts of the sky at day and night.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the cosmological significance of CMB radiation?

A

evidence of the big bang (cooling universe)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is the significance of ripples in the CMB?

A

may show distribution of dark matter/galaxies in the early universe.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How can the Hubble constant be used to estimate the age of the universe?

A

Convert the Hubble constant to an ‘inverse time’. If the graph was steep then the Universe would be young. The less steep it is the older the Universe: t = d / v

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Describe the appearance of an open cluster E.g. the pleiades

A

fuzzy appearance. quite faint with a few visible stars.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What was the next year after 1976 which solar maximum occurred?

A

1981

43
Q

why are there more lunar eclipses that solar eclipses?

A

Because the earth is bigger and will cast a bigger shadow than the moon (more likely for the earth to block out the sun than the moon)

44
Q

Describe the naked eye appearance of the milky way

A

Strip/band across the sky with fuzzy lights/stars

45
Q

Explain how measurements using long exposure photographs of circumpolar stars can be used to determine the rotation period of the Earth.

A

Stars appear the circle around polaris (when being photoed using long exposure) and complete the circle after 24hrs. so every hour the complete 15 degrees of the rotation. we can work out the rotation period by seeing when the star makes the full circle.

46
Q

How do astronomers experimentally test the possible water origin coming from comets?

A

They land space probes on comets and sample matter to compare it to elements on earth

47
Q

obaf…

A

…gkm

48
Q

Why is the dust tail curved?

A

because particles spread out

49
Q

What are the specific purposes of two instruments in the ALSEP?

A

To study moonquakes

testing for an atmosphere

50
Q

What is the giant impact hypothesis?

A

Early in the formation of the solar system a large body of rock, about the size of Mars, crashed into earth and the debris went into orbit and collected together to form the moon: backed up by similar isotopic abundances on the moon and earth.

51
Q

What is Oscillating?

A

The universe will undergo a period of expanding then shrinking (Many big bangs and big crunches)

52
Q

What is dark matter?

A

Matter that does not give off any detectable radiation but has gravitational effects.

53
Q

What is dark energy?

A

Energy proposed to explain why the expansion of the Universe might be accelerating.

54
Q

Hubble constant

A

The Hubble Constant is the unit of measurement used to describe the expansion of the universe.

55
Q

Steady state

A

The theory that the Universe is expanding, but new matter is constantly being created, so that the overall density of the Universe remains constant.

56
Q

How do astronomers detect black holes?

A

x-rays

57
Q

how do you know the maria are made out of younger rock?

A

less craters

58
Q

How are wrinkle ridges different to rille?

A

wrinkle ridges are longer and wider

59
Q

what did galileo discover?

A

Venuses phases + Jupiter moons

60
Q

Who discovered the inverse square law?

A

netwon

61
Q

where is dust + young stars found?

A

spiral arms

62
Q

What is a Parsec?

A

The distance to a star which has a parallax angle of 1 arc second

63
Q

What are three methods used to find new planets?

A

transit method- seeing if light levels drop is a planet transits its star
the radial velocity method- use Doppler shifting to see if a planets gravity affects the star
the astrometry method- measuring a stars position very precisely then measuring its wobbles due to a planets gravity

64
Q

What does the ecliptic show?

A

The motion of the sun

65
Q

What can be obtained from studying the spectrum of a star?

A

size, temperature, chemical composition.

66
Q

What is the purpose of WMAP (CMB radiation)?

A

to study ripples/variation in more detail.

67
Q

Why was WMAP (SCB radiation) observations important?

A

shows that CMB is leftover radiation from the big bang and allows astronomers to estimate proportion of dark matter/ dark energy.

68
Q

What are neptunes moons?

A

Kuiper belt objects

69
Q

how do we know the earth is not flat?

A

sattelites/images from space + you see ships disappear over the horizon

70
Q

When a star is due south of an observer What measure of its position reaches maximum?

A

elevation

71
Q

Culmilation

A

A celestial body to reach the meridain/ highest point

72
Q

A collection of meteoroids from a dust tail of a comet?

A

Meteor stream

73
Q

Why do the biggest telescopes use mirrors?

A

no chromatic aberration

74
Q

what does out atmosphere absorb?

A

UV, IR, X-ray, Gamma rays

75
Q

What is the latitude of sunspots during solar maximum?

A

+- 20

76
Q

Soltice

A

longest or shortest day of the year

77
Q

Equinox

A

length of day and night are equal

78
Q

What is the SETI project

A

to search for intelligent life

79
Q

We know black holes exist becasue of…

A

orbitting stars

80
Q

supernova remenent…

A

dust and gas left after a star explosion

81
Q

What is the scale which impact hazards are measured?

A

torino

82
Q

What is the Cepheid Variables?

A

Cepheid Variables are very large, luminous, yellow stars. They change in brightness very regularly

83
Q

What is a Cosmic ray?

A

Cosmic rays are energetic, subatomic particles that arrive from outside the Earth’s atmosphere. The lowest energy cosmic rays are produced by ordinary stars like the Sun. For example, during a solar flare many particles are ejected from the Sun.

84
Q

What is Cosmology?

A

the origin and evolution of the universe

85
Q

What is Aperture?

A

a space through which light passes in an optical or photographic instrument

86
Q

What is Apogee?

A

the point in the orbit of the moon or a satellite at which it is furthest from the earth.

87
Q

Accretion

A

Where dust and gas accumulate into stars or planets

88
Q

What is Perigee?

A

the point in the orbit of the moon or a satellite at which it is closest to the earth the earth.

89
Q

What is perihelion?

A

the point in the orbit of a planet, asteroid, or comet at which it is closest to the sun.

90
Q

What two gases absorb large amounts of infra-red radiation?

A

water vapour, methane, Carbon dioxide

91
Q

How do astronomers work out the distance to a Cepheid variable star?

A

determine the time period and use period-luminosity equation to obtain M. rearrange M= m+5-5log(d) to calculate d

92
Q

What is a primary eclipse?

A

when the smaller of the binary stars is infront

93
Q

How can you safely observe the transit of venus??

A

Look at the sun through solar filters or pinhole projecters

94
Q

What is the y axis of the hertz-sprung russel diagram?

A

Luminosity

95
Q

How was ceres discovered?

A

piazzi - with a large reflecting telescope while searching the zodiac

96
Q

How was Pluto discovered?

A

tombaugh - it was shown in repeated photos

97
Q

What is greatest elongation?

A

when a planet appears the furthest from the sun it can be, e.g. the sun is on the east horizon and the planet is on the west horizon.

98
Q

What are the van allen radiation belts?

A

Regions of radiation that encircle the earth. One effect is trapping charged particles which can damage satellites.The radiation belts are a result of the Earth’s magnetic field, and contain mostly protons.

99
Q

What is it called when one object blocks another from view? (passes in front of it.)

A

Occulation

100
Q

Inclination

A

Inclination is a measure of how the plane of an orbit is tilted with respect to the plane of the ecliptic.

101
Q

ionsphere

A

the layer of the earth’s atmosphere which contains a high concentration of ions and free electrons and is able to reflect radio waves.

102
Q

heliosphere

A

the region surrounding the Sun and the solar system that is filled with the solar magnetic field and the protons and electrons of the solar wind.

103
Q

Rotation period of earth =

A

angle of arc