ASTRO 7N - UNIT 4 PART 1 (convo)
UPDATED ACTUAL Exam Questions and
CORRECT Answers
The brightest stars in the Pleiades are B and A Main Sequence stars. How old do you suppose
that cluster is then? - CORRECT ANSWER - Tens to a hundred million years old
Based on the HR diagram I showed you, how old is this cluster? - CORRECT ANSWER -
About 8 billion years old
The main-sequence turnoff of a star cluster tells us the cluster's - CORRECT ANSWER -
age
Which of the following main-sequence turnoffs indicates the oldest globular cluster? -
CORRECT ANSWER - G2
Can you tell me which cluster of the following is the oldest? - CORRECT ANSWER -
M67
Gas is added to the interstellar medium by supernovae and by planetary nebulae like this one.
From what you remember of stellar evolution, what kind of gas would you expect that to be? -
CORRECT ANSWER - Gas that has a mix of heavier elements in it, such as carbon,
oxygen, silicon, iron, etc.
Do you remember what gets left behind in the middle of a planetary nebula? - CORRECT
ANSWER - A white dwarf
What is one way the concentric rings in the Cat's Eye nebula might have formed? - CORRECT
ANSWER - The gas might have been ejected in pulses.
, Why do you suppose this nebula has a certain symmetry? - CORRECT ANSWER -
Bipolar jets are creating matching shapes on both sides.
What causes the red glow in the Helix Nebula? - CORRECT ANSWER - Hydrogen gas
heated by central remnant
How is the donut-shape of the Helix nebula caused by our line-of-sight? - CORRECT
ANSWER - There are multiple disks of dust and gas at different angles.
V838 Monocerotis, Supernova Remnant. The gas and dust around the star is... - CORRECT
ANSWER - being illuminated up by the star behind it
The amount of light given off during a Type 1 supernova is very similar to that of a type 2 core
collapse supernova. What about their spectra? What are these different types of explosions made
of? - CORRECT ANSWER - They should be similar, but only type 2 supernovae have
hydrogen lines
Cassiopeia A: The blast wave from the supernova is moving at... - CORRECT ANSWER -
16,000,000 kilometers per hour
Cassiopeia A: What elements are in the supernova remnant? - CORRECT ANSWER - All
of the above (Oxygen, sulfur, hydrogen, nitrogen)
Cassiopeia A: How long ago did this supernova occur? - CORRECT ANSWER - 340
years ago
Crab nebula: What year did people on Earth see this star explode? - CORRECT
ANSWER - 1054
Crab nebula: The colors are produced by the same elements as before - hydrogen, oxygen, sulfur.
But what about that blueish haze in the middle? - CORRECT ANSWER - It is produced
by accelerated electrons.
UPDATED ACTUAL Exam Questions and
CORRECT Answers
The brightest stars in the Pleiades are B and A Main Sequence stars. How old do you suppose
that cluster is then? - CORRECT ANSWER - Tens to a hundred million years old
Based on the HR diagram I showed you, how old is this cluster? - CORRECT ANSWER -
About 8 billion years old
The main-sequence turnoff of a star cluster tells us the cluster's - CORRECT ANSWER -
age
Which of the following main-sequence turnoffs indicates the oldest globular cluster? -
CORRECT ANSWER - G2
Can you tell me which cluster of the following is the oldest? - CORRECT ANSWER -
M67
Gas is added to the interstellar medium by supernovae and by planetary nebulae like this one.
From what you remember of stellar evolution, what kind of gas would you expect that to be? -
CORRECT ANSWER - Gas that has a mix of heavier elements in it, such as carbon,
oxygen, silicon, iron, etc.
Do you remember what gets left behind in the middle of a planetary nebula? - CORRECT
ANSWER - A white dwarf
What is one way the concentric rings in the Cat's Eye nebula might have formed? - CORRECT
ANSWER - The gas might have been ejected in pulses.
, Why do you suppose this nebula has a certain symmetry? - CORRECT ANSWER -
Bipolar jets are creating matching shapes on both sides.
What causes the red glow in the Helix Nebula? - CORRECT ANSWER - Hydrogen gas
heated by central remnant
How is the donut-shape of the Helix nebula caused by our line-of-sight? - CORRECT
ANSWER - There are multiple disks of dust and gas at different angles.
V838 Monocerotis, Supernova Remnant. The gas and dust around the star is... - CORRECT
ANSWER - being illuminated up by the star behind it
The amount of light given off during a Type 1 supernova is very similar to that of a type 2 core
collapse supernova. What about their spectra? What are these different types of explosions made
of? - CORRECT ANSWER - They should be similar, but only type 2 supernovae have
hydrogen lines
Cassiopeia A: The blast wave from the supernova is moving at... - CORRECT ANSWER -
16,000,000 kilometers per hour
Cassiopeia A: What elements are in the supernova remnant? - CORRECT ANSWER - All
of the above (Oxygen, sulfur, hydrogen, nitrogen)
Cassiopeia A: How long ago did this supernova occur? - CORRECT ANSWER - 340
years ago
Crab nebula: What year did people on Earth see this star explode? - CORRECT
ANSWER - 1054
Crab nebula: The colors are produced by the same elements as before - hydrogen, oxygen, sulfur.
But what about that blueish haze in the middle? - CORRECT ANSWER - It is produced
by accelerated electrons.
