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Online reading assignment: the Milky Way (SLO campus)

Astronomy 210, fall semester 2018
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 Milky Way's shape, size and composition and spiral arm structure and formation.


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.
"Something that is interesting to me from this chapter is: was how the Milky Way was named and that was by the Greeks because they thought it looked like a milky river. I used to take camping trips all the time and I would love finding great spots to look at stars and loved finding certain locations where the Milky Way was clear, vibrant, and beautiful."

"The sun and our solar system are located near the edge of the disk of the Milky Way."

"The shape of the Milky Way very interesting because I had no idea what the shape of our galaxy was before reading the presentation."

"The analogy about looking for tall buildings was a way to help us figure out where a downtown area might be."

"Learning about the fog model and methods of using landmarks in the Milky Way to be able to orient ourselves in our galaxy."

"The Milky Way galaxy is a spiral disk with a halo of globular clusters."

"The way in which they were able to determine that we were not in the center of the universe."

"That we were able to find out somewhat where we are in the galaxy and what kind of galaxy we are without actually seeing our galaxy from the outside."

"The arms of the Milky Way are similar to the arms of a starfish."

"Dark matter is responsible for a significant portion of mass in the galaxy. It does not reflect light but is detectable via stellar transit or effect on visible object."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I don't understand how globular clusters tell help us determine the size of our galaxy."

"Globular clusters confuse me because I don't understand where they are located. It says above and below the disk of the Milky Way. So are globular clusters not other galaxies?"

"Global cluster positions are hard for me to wrap my head around it."

"What the arms are made up of?"

"What causes these galaxies to maintain this form. What gravitational pull is being exerted on them to maintain this form?"

"How you find the mass of a galaxy. The book states that to find the mass you must look at orbital motion of the stars but I don't get how that pertains to mass."

"Kepler's third law--I felt like I couldn't grasp my head around the idea."

"Dark matter is pretty confusing and hard to picture."

"What is dark matter? It seems like we don't have any explanation for any of it."

In your experience, how much of the "Milky Way" (the band of faint stars across the celestial sphere) have you been able to see in the night sky?
As much as can be seen with the naked eye.  ******** [8]
Not very much.  *********** [11]
Barely seen it.  ***** [5]
(Never been able to see it.)  * [1]
(Unsure/guessing/lost/help!)  [0]

Using the most powerful light-gathering optical telescopes in the darkest skies, __________ of the stars in our entire galaxy can be observed from Earth.
1%.  ***** [5]
5%.  ********* [9]
10%.  ********* [9]
50%.  ***** [5]
100%.  [0]
(Unsure/guessing/lost/help!)  [0]

If you did not have access to a mirror while camping, what could you do to find out whether or not you're having a bad hair day?
"Other people."

"Our friends could tell us if we look like a spiral galaxy with arms or a messy blob."

"Well if I was camping. I could use my phone and use the camera on that, or I could look into water and see my reflection."

"Open the camera or Snapchat on my phone."

"Try to use your shadow."

"Look in the reflection of the water. Or ask someone. Or don't care."

"Touch my hair and feel the mess out."

"Feel it with your hands to see if you have spiral arms or are like a blob."

"I usually just put my hair up or a hat while camping."

"Honestly if I was camping I would just put my hair in a bun."

Look at PimpStar Rims (*.html) for cars, or MonkeyLectric Rims (*.html) for bikes. Briefly explain how they work.
"The blinking lights can be timed to the speed of the wheel to light up at the right time to produce a pattern on a wheel."

"They have LED lights inside the rims and are connected via wi-fi to them and once you send the image to them they maintain the image even though your wheels are turning through the sequence."

"Persistence of vision; your eyes and brain don't refresh visual information as fast as it's coming in and these lights turn on and off in patterns, creating images."

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Where is the best location to see the Milky Way clearly?" (Anywhere as far away from city light as possible. Try going out to Carrizo Plain.)

"Is it possible that 'dark matter' is not matter at all, but rather distortions in space-time similar to ripples on a pond? Instead of being caused by matter per se it would be more analogous to the wearing-out of fabric on a quilt?"

"In what ways does dark matter interact with regular matter other than gravitationally?" (That is not yet known. That's why it's dark, because we can't even see it.)

"Do you have one of those rim lights to write 'P-dog?'" (Yes, I do. If you see me rolling at night, don't be hating.)

"Is Midterm 2 harder in regards to material than Midterm 1?"

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