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 history of the Milky Way and big bang clues, a comic strip adaptation of Neil deGrasse Tyson's "The Most Astounding Fact" 2008 interview for TIME magazine, and Minute Physics' video explanation of Olbers' paradox.
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.
"This suggests a simple 'monolithic collapse' model of Milky Way evolution, where hydrogen for star formation gradually migrated from a spherical shape to its current flattened disk shape. This model is perhaps too simple."
"I think it is mindblowing that we are able to see (with the naked eye) light that is over 2.5 million years old. Literally like a time machine that see things we can't touch, but just admire. It makes me feel really small and insignificant in the expanse of our universe."
"One light year is crazy to me, let alone how far away everything is based on light years. It's mind-blowing."
"The thought that telescopes are technically time machines is really abstract."
"That at the start of the universe was primarily hydrogen interesting because that is how the all of the stars started to form."
"Learning about how the universe is expanding. Also how scientists used this information to look into the past to find out how old the universe is."
"I found the 'edge of time' to be interesting. The thought of the universe having a finite age isn't something I thought of before. We always want to think of something having an end, but the universe is expanding."
"That all galaxies are fleeing away from the Milky Way."
"That the big bang occurred everywhere; before I assumed it happened in a specific location."
"The part concerning the infinity of space really interests me it always has. Is there and end to it all? If there is whats beyond the end of space? It really gets me."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Lookback time was confusing at first, but having the concept of light years explained cleared this up."
"Understanding which stars have more or less metals then others."
"Metal-rich versus metal-poor stars and how this relates to their location in the galaxy."
"Need some review over what produces a specific kind of element. I couldn't find it within the blog lecture, but I'm sure it's there. Just need some further review."
"How the stars and later type II supernovas created metals in its core if it didn't have any metals to start out with."
"The difference between population I stars and population II stars? What confuses me is how the ages of population I stars can be older than population II stars?"
"I find it confusing to understand how the universe is expanding everywhere. What is causing this?"
"Wow is there an 'edge of time.' and what is beyond that?"
"I am confused if we can only see 14 billion light years away as that is what they predict how old our universe is."
"How can astronomers and other scientist say the Universe and all of the things within it are a certain age? The textbook states, the ages of particular parts of the universe are 'somewhat uncertain,' but scientist still claim their theories are correct without any real, provable evidence."
Indicate how the amount of these elements in the universe have changed over time.
(Only correct responses shown.)
Hydrogen: decreased [47%]
Metals (elements heavier than hydrogen and helium): increased [95%]
The outermost layers of __________ are more abundant in metals (elements heavier than hydrogen and helium).
extremely old stars that formed a long time ago.   ***********  young stars that formed very recently.   ********  (There is a tie.)    (Neither, as stars cannot have metals.)    (Unsure/guessing/lost/help!)   
Indicate what produced these elements.
(Only correct responses shown.)
Hydrogen in the sun's core: the very early universe [64%]
Helium in the sun's core: the sun [32%]
Carbon in your body: another star, in the past [58%]
Calcium in your bones: another star, in the past [47%]
Iron in your blood: another star, in the past [47%]
Gold and silver from mines: another star, in the past [32%]
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Is time travel really real?" (No, but looking back in time is real.)
"Look-back time is absolutely insane. How are we seeing Deneb as it was 1,400 if we are looking in the present? Or Andromeda, how are we seeing the stars from millions of years ago? I'm so confused? HELP P-DOG!"
"How far away is the most distance star or galaxy we can see and if it is more that 13.8 billion light years away how can we see it?" (Since as we look further and further out, we see things further and further back in time, so if we far out enough, we'll eventually be looking so far back in time that we will see what the universe was like before the first stars were even born; this is about 14 billion light years away, as it was 14 billion years ago.)
"I was a little confused with where the elements were produced."
"Please explain the relationship between population I and II type stars."
"Why is the universe expanding?"