Online reading assignment: medium-mass stars, massive stars, neutron stars and black holes (SLO campus)

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on the evolution of medium-mass stars, massive stars, and on neutron stars and black holes.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"Star death is interesting to me because I think it is crazy that it even happens!"

"If you jumped at a black hole you would appear to fall forever. This doesn't make sense to me and I'm wondering how long you are actually falling for."

"Stars steal hydrogen from each other to create explosions. It was interesting to me because I did not know how that process worked."

"Red giant stage stars can lose mass due to strong stellar winds. That puts the Big Bad Wolf to shame. I think this is personally interesting for me because I never imagined there being wind in outer space--this is definitely leading me to reconsider my travel plans."

"Stars have several ways they can end. And pretty crazy that all life comes from star dust."

"White dwarfs are not really stars but are actually considered compact objects. I also found it a little disconcerting that as our sun begins to die all the matter on earth will be incinerated by the growing size of the sun and ultimately no chance will exist to sustain life on our planet. Fortunately, this will not happen for another couple of billion years so I do not have to add this to my list of things on my plate to concern myself with."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"How they can figure out how stars are made even though we cant get close to them."

"How a nova and a type Ia supernova occur. I don't understand how a star can just suck hydrogen out of another star."

"Black holes. I don't understand how the core of a star become small enough, (the radius of zero?), that the escape velocity in a region around it is so large that light cannot escape. What? Where does the object 'fall to' if it's a hole?"

"[Medium-mass] main sequence stars becoming giants is confusing. I thought that once a star died it was dead and couldn't become another star."
The first rule of astronomy class is...
"Don't talk about astronomy class." (2 responses.)

"Show up to class." (3 responses.)

"Sit still and ask lots of questions."

"Be a star. :3"

"Respect P-dog."

"P-Dog is the best." (2 responses.)

"Call you P-dog." (2 responses.)

"I don't know." (2 responses.)

"Have fun." (2 responses.)

"Abide by all of Cuesta's policies."

"Do not leave questions blank." (3 responses.)

"You are part of the universe and not just an observer."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"How do they know that a black hole is a hole if everything gets distorted and/or destroyed by tidal forces long before it even reaches the event horizon?"

"I feel like I'm in a dream within a dream whenever I go over astronomy stuff."

"Theoretically stars with masses larger than 15 solar masses form black holes when they die. Does that mean there's tons and tons of black holes?" (Yes, but massive stars are relatively rare compared to the more common medium-mass and low-mass stars in the universe, such that black holes would be vastly outnumbered.)

"Can we do something fun for Halloween? Like have a house party!" (We'll have a quiz. And then, there will be learning. What could possibly be more fun?)

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