The Galaxies and the Universe
Practice Test
1.
Constellations that can be seen all year long from a certain location are __________.
a.
circumpolar
b.
cluster
c.
seasonal
d.
binary
2.
From what does a star form?
a.
a main sequence
b.
a binary
c.
a spectra
d.
a nebula
3.
A __________ is visible light arranged according to wavelength.
a.
emission spectrum
b.
spectrum
c.
auroras
d.
solar flare
4.
Why is Pluto NOT classified as a terrestrial planet?
a.
it's distance from the Sun
b.
it's low density and small size
c.
the angle of it's orbital plane
d.
it's atmospheric composition
5.
How is the composition of a white dwarf determined?
a.
by its luminosity
b.
by the size of the supernova
c.
by how many reaction phases it went through
d.
by the size of its planetary nebula
6.
From where on the Sun does the solar wind escape?
a.
solar flares
b.
photosphere
c.
coronal holes
d.
sunspots
7.
Most of the mass in cluster galaxies is __________.
a.
spinning
b.
pulsating
c.
invisible
d.
visible
8.
The wobble in Earth's axis is called __________.
a.
precession
b.
seasons
c.
eccentricity
d.
tilt
9.
The Sun is __________.
a.
a Population 2 star
b.
a red giant
c.
a Population 1 star
d.
made 99.9 percent of hydrogen and helium
10.
Why do astronomers rely on computer models for an explanation of the Sun's interior?
a.
They need more than the observations of the interior.
b.
The interior is only visible during a solar eclipse.
c.
The interior can't be directly observed.
d.
to remove the effects of the solar wind
11.
What shape describes the orbits of the planets?
a.
a circle
b.
a sphere
c.
a line
d.
an ellipse
12.
The objects that eventually formed planets by colliding and merging are called __________.
a.
stars
b.
planetesimals
c.
asteroids
d.
solar nebula
13.
The eccentricity of a perfect circle is __________ and a very elongated ellipse is __________.
a.
one, zero
b.
zero, one
c.
nearly zero, one
d.
zero, nearly one
14.
What are the three labeled parts of the comet shown in the figure?
a.
coma, nucleus, tail
b.
corona, nucleus, end
c.
ice core, cloud, fan
d.
head, cone, tail
15.
In the Big Bang theory, what balances the momentum of the expansion of the universe?
a.
the critical density of the universe
b.
the momentum of the galaxies
c.
the outward force of gravity
d.
the inward force of gravity
16.
Is the rate of the universe expansion speeding up or slowing down?
a.
It was speeding up, but now it is slowing down.
b.
It was slowing down, but now it is speeding up.
c.
It has always been slowing down.
d.
It has always been speeding up.
17.
Why do variable stars pulsate in brightness?
a.
movement at a fixed rate
b.
constant contraction
c.
expansion and contraction of their outer layers
d.
gain in mass
18.
What causes Uranus' blue appearance?
a.
surfuric acid in its atmosphere
b.
the vast oceans
c.
the ammonia ice droplets
d.
the methane in its atmosphere
19.
Which of the galaxies shown has the same shape of our galaxy?
a.
D
b.
B
c.
A
d.
C
20.
Mercury's extremely slow spin causes only __________ days to pass in __________ of Mercury's years.
a.
one hundred, one
b.
three, two
c.
twenty-four, one
d.
one, two hundred
