問題一覧
1
The most powerful tool used by astronomers to determine the properties of stars galaxies and nebulae is
spectroscopy
2
a type of star that has turned out to be extremely useful for measuring distances is
the Cepheid variable
3
in astronomy a(n) _____ is a source that has a known luminosity and can be used to determine distances
standard candle
4
Which of these is the best description of the orbital motion of a binarystar system?
Both stars orbit a common center mass
5
A(n) _____ has orbits which are edge-on, and the stars cross in front of each other so that the light of one starts periodically diminished by the other passing in front of it.
eclipsing binary
6
when one of the stars in a spectroscopic binary is moving toward the earth, in its orbit, we observe
that the lines in its spectrum show a blue shift
7
which of the following characteristics of a single star (one that moves through space alone) is it difficult to measure directly?
it's mass
8
A light curve for a star measures how it's brightness changes with
time
9
Dappler shift observations of a ______ can enable astronomers to calculate _____ of its individual stars
spectroscopic binary stars ; masses
10
Stars in the main sequence obey a mass-luminosity relation. According to this relation,
luminosity is proportional to mass to the fourth power (luminosity increases strongly with mass)
11
the period-luminosity relationship for Cepheid variables was discovered by
Henrietta Leavitt
12
Why did it take astronomers until 1837 to successfully measure the distance to a star? Because:
the amount of parallax shift is so small it only became detectable with improved technology
13
A star located 1 parsec from Earth will have a parallax angle of:
1 arc" (one second of arc)
14
Which formulaic used by astronomers to determine the total energy output of a star?
L = 4[pi]r^2oT^4
15
the most recent data used by astronomers to measure the parallax angles comes from:
the Gaia spacecraft
16
Which of these stars is located closest to Earth? Remember... D = 1/ p
Star C is located in the constellation Coma Berenices has a parallax angle of 0.00817
17
The absolute magnitude of a star is:
the magnitude of a star observed from a distance of 10pc.
18
The Apparent magnitude of a star is:
the magnitude observed from earth
19
in other to use the Distance Modulus astronomers need:
both the apparent magnitude and the absolute magnitude of the object
20
Which star from table 2-1 would appear the brightest to an observer on Earth?
Sirius
21
Based on the information in Table 2-1, how many times brighter is Altais than HL Tauri
100
22
NCP
c
23
SCP
d
24
Celestial Equator
a
25
Polaris
b
26
Meridian
e
27
What do we call the apparent path of the sun
the ecliptic
28
The band of 13 constellations through which the sun travels in one year. The:
zodiac
29
Imaginary line that divides the celestial sphere into Noth and Soith Hemispheres
celestial equator
30
Imaginary line that divides the celestial sphere into East and West hemispheres
meridian
31
Which of the following is not a common use of the constellations
to verify stellar distances
32
When using the Bayer naming system, a(n) _____ letter indicates its brightness relative to the other stars in the constellation.
Greek
33
The modern definition of "constellation" is a(n):
area in the sky
34
The _____ of a star, or any celestial body, is measured in hours and minutes and is an East/West coordinate.
Right Ascension
35
A constellation contains a group of stars
all within a boundary in the same area of the sky
36
the modern definition of "asterism" is a(n)
recognizable pattern of stars
37
the _____ of a star, or any celestial body, is measure in degrees and minutes and is a Noth/South Coordinate
Declination
38
What is the name of the star located at Dec. 8* 52m, RA. 19h 50m
a in Aquila
39
What is the name of the star located in Dec. 12* 33m , RA. 17h 35m
a in Ophiuchus
40
What is the name of the constellation located in Dec. 16, RA 20h 40m
Delphinus
41
What is the Declination of the NCP, Noth Celestial Pole
Dec. 90
42
The Renaissance Astronomer that proposed a Jeliocentric Solar System
Copernicus
43
Which of the following was not discovered by Galileo
the motions of Mars prove the geocentric model
44
According to Kepler's second law, there is a relationship between the speed a planet travels and its:
distance from the Sun
45
Two motions are required to produce an orbit, what are they?
tangential motion and the acceleration of gravity
46
Newton's first law of motion explains that the Moon doesn't travel in a straight line at a constant velocity because
it is acted upon by a force
47
Newton's Second Law of Motion explains that in order to:
accelerate mass you must apply a force
48
what two factors are responsible for determining the strength of the gravitational attraction between any two objects?
mass and separation
49
Planet A has a mass of 4 Earths and a radius of 6 Earths. Planet B has a mass of 4 Earths and a radius of 3 Earths. On which planet would you feel a smaller force pull gravity?
Planet A
50
According to _____ "Gravity is cause by the curvature of Spacetime, and Space time is warped (curved) by mass.
Einstein's General Theory of Relativity
51
Why were the radio signals from the Martian Viking landers delayed as they traveled past the Sun towards the Earth?
The Sun's mass curves Spacetime
52
What is the order of star colors with increasing temperature
red, yellow, blue
53
Astronomers can determine the surface temperature of a starusing which of these?
Wein's Law
54
If the light source is moving away from an observer, the observed wavelength will:
get longer, and hence Red-shifted
55
According the Kirchoff's first law of spectroscopy:
a hot solid, or a hot, dense gas produces a continuous spectrum
56
Radiation from a distant Gamma Burst, millions of light years away from Earth:
will not Pentwater Earth's atmosphere and reach the ground
57
You are standing near a railroad track and a train is moving toward you at 60 mph and blowing its horn. What will you notice as the train approaches you?
as the train approaches, the pitch of the horn gets higher
58
Light (electromagnetic radiaton) is produced as:
electrons transition to lower energy levels
59
_____ is a measure of the average kinetic energy, the speed, of the gas particles in a system
Temperature
60
Which of these is the correct order of EMR from highest energy to lowest?
gamma, visible, infra-red, microwave, radio
61
Why do the different elements emit different spectra? Because:
different atoms have different numbers of electrons transitioning from different energy levels
62
You are lying out at the beach and enioying the wam sunshine, ou look up in the sky and you see the Sun. What pant of the Sun are you looking at? (yes 1 know, 1 shouldn't finish a sentence which a preposition)
photosphere
63
Solar wind particles can be captured by Earth's magnetic field. When these particles spiral down into the atmosphere, they create:
the auroras (northern and Southern lights)
64
What is the best reason astronomers have come up with to explain why sunspots are cooler and darker than their surrounding areas?
Sunspots are places where strong magnetic fields prevent the upward motion and the release of hot gases from the envelope
65
According to the formula E = mc^2 :
a small amount of mass can be converted into a substantial amount of energy
66
What are the three layers of the Sun's atmosphere, in order of increasing distance from the surface?
Photosphere, chromosphere, corona
67
Granulation is:
created as hot games rise to the photosphere from below
68
In the envelope of main sequence stars, energy is transported by:
Radiation and Convection
69
The rotation of a Main Sequence star is:
faster at the equator than it is at the poles
70
The ______ extends several million kilometers from the outside edge of the chromosphere and has a temperature range of 1 million to 2 million Kelvin.
Corona
71
All Main Sequence stars release energy as _____ from the Photosphere, ______ from the Chromosphere, and _____ from the Corona.
Visible light, Ultra-Violet, X Ray
72
What did Harlow Shapley discover about globular clusters that allowed him to determine the size of the galaxy and the Sun's location within it?
the center of distribution of clusters is far from the Sun
73
Where would you look to find the largest number of Population I stars in the Milky Way Galaxy?
the disk
74
How was Edwin Hubble able to determine distances to nearby galaxies? By
observing changes to variable stars
75
The red color we see in photographs of nebulae comes from which element?
Hydrogen
76
Our galaxy, The Milky Way, is classified as a(n) _____ galaxy.
Barred Spiral
77
Where would you find a large collection of Population II stars in the Milky Way Galaxy?
in globular clusters
78
The blue color of the nebulosity surrounding the Pleiades, an open cluster, is produced by
starlight reflected by ice and dust particles
79
Which of the following best describes a SAa galaxy?
large, bright nucleus and tight spiral arms
80
At the center of the Milky Way galaxy is a superlative black hole called:
Sagittarius A
81
A tuning fork diagram is shown below. Which of the labeled figures represents an ordinary SBc galaxy?
3
82
The amount of time a star can remain on the main sequence is determined by:
it's mass
83
As an evolving stars expands its surface, the temperature of the envelope decreases. As a result, what happens to the star?
The star grows, becomes a giant and the star's overall color becomes redder
84
What conditions must be met in order for an object to be considered a main sequence star?
all the above
85
What do Red Giant stars, Red Supergiant stars and AGB (Asymptotic Giant Branch) stars all have in common? They all:
have Kelvin-Helmholtz heating
86
Arrange the following in order of evolution of a 1 M Main Sequence star. 1.Planetary Nebula/White Dwarf 2. Main Sequence 3. Horizontal Branch 4. Red Giant 5. Asymptotic Giant Branch
2, 4, 3, 5, 1
87
In a high mass star, the process of fusing iron (Fe) absorbs energy. As a result:
the core collapses in a catastrophic event
88
Horizontal Branch stars have core fusion, Hydrostatic and Thermal Equilibrium. Why are they NOT classified as a Main Sequenc3 stars because:
they have Helium core fusion
89
What is a Planetary nebula?
the disconnected envelope of a dying low-mass star
90
As Planetary nebulae expand they emit the spectra of many elements. What is the source of energy that ionizes these clouds?
ultraviolet radiation from the White Dwarf star (core)
91
Helium fusion is called the triple alpha process because:
the helium nucleus is known as an alpha particle
92
What is the correct order of the steps in "Scientific Method"?
Ask a question, research, formulate your hypothesis, test the hypothesis, analyze your data and propose your theory, publish your results for peer review
93
The Milky Way Galaxy
contains approximately 400 billion stars
94
The location of the Earth in the Milky Way Galaxy is:
approximately 30,000 light years from the center
95
Which sequence is correct when ordered by increasing size?
Earth, Solar System, Solar Neighborhood, Milky Way, Local Group, Supercluster, Universe
96
How many stars are there in the solar system?
1
97
The star Altair is approximately 16 light-years from Earth. That means:
the light we see left Altair 16 years ago