Astronomy 120 - Stars and Galaxies » Fall 2022 » Unit 8 Quiz
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Question #1
In order to see through a dark nebula and observe the stars behind it, we must make observations within the range of EM radiation.
A.
infrared
B.
visible
C.
gamma
D.
X-ray
Question #2
The hydrogen and helium atoms found in the ISM have existed since the Big Bang, which occurred almost how many years ago?
A.
4.6 billion
B.
13.7 million
C.
460,000
D.
13.7 billion
Question #3
Radiation with a wavelength of 21 cm is emitted as a result of
A.
the electron of hydrogen flipping upside down.
B.
low energy vibrations.
C.
high energy vibrations.
D.
the transitioning from orbital to orbital of hydrogen's electron.
Question #4
There is virtually no interstellar medium in the galaxy.
A.
False
B.
True
Question #5
The interstellar medium is made up of
A.
the emptiness of space.
B.
medium amounts of interstellars.
C.
mostly dust and a bit of gas.
D.
mostly gas and a bit of dust.
Question #6
The red light observed in emission nebulae results from photons of light emitted from
A.
hydrogen.
B.
carbon monoxide.
C.
oxygen.
D.
helium.
Question #7
The overall reduction in intensity of observed starlight results from
A.
interstellar extinction.
B.
absorptive gases.
C.
reducing nebulae.
D.
absorption spectra.
Question #8
Molecular nebulae are virtually invisible. The hydrogen atoms, joined together as H2, don't emit any light of any wavelength. But they are known to hang out with other molecules that do emit light at 1.3 mm and 2.6 mm. What are these other molecules?
A.
CH (carbyne molecules)
B.
O2 (oxygen molecules)
C.
CO (carbon monoxide)
D.
H2O (water molecules - or dihydrogen monoxide, if you will)
Question #9
If a protostar's core reaches a temperature of 6 million degrees, it will start fusing hydrogen into helium.
A.
False
B.
True
Question #10
The minimum temperature needed to ignite thermonuclear fusion in main sequence stars is
A.
5800 K
B.
5 million K
C.
333,000 K
D.
10 million K
Question #11
Which of the following is not a possible trigger for molecular cloud collapse?
A.
collision of ISM clouds
B.
supernovae
C.
starlight
D.
solar flares
Question #12
After the dense cores of the Bok globules gain sufficient mass, the very center of these cores begins to heat up. This is due to the
A.
presence of high energy particles.
B.
thermonuclear fusion process increasing its rate of helium production.
C.
increased pressure from the overlying layers of mass above the cores.
D.
spin flip of hydrogen.
Question #13
"A star is born" when
A.
hydrostatic equilibrium is reached.
B.
a Bok globule becomes big enough to collapse.
C.
thermonuclear fusion begins in its core.
D.
Lady Gaga and Bradley Cooper sing "Shallow" together at the Oscars.
Question #14
When the core of a protostar is sufficiently hot, nuclear fusion of begins.
A.
heliogen
B.
hydrogen
C.
helium
D.
atoms
Question #15
What force causes the atoms and molecules of the nebula to start forming more dense regions?
A.
electromagnetic force
B.
the force of nature
C.
the force of gravity
D.
F = ma
Question #16
The evolutionary path of a protostar on the HR Diagram is called its
A.
Barnard displacement.
B.
Hayashi track.
C.
Subaru path.
D.
Hiromasa track.
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