Classroom Stories: Missing the "Aha!" Moments during Online Teaching

By Stacy Palen

I’ve been talking to a lot of people about the transition to online instruction. Most of these conversations have been with people who are not academics and who seem to have the idea that I sit around eating bonbons and drinking bourbon in the afternoon now that I don’t have to “actually” work. Once I take a deep breath, I find myself saying, “I hate it,” which gives me the opportunity to reflect about why I hate it.

I had not taught an all-online course before, so there was an enormous learning curve. This problem was magnified because I was moving five distinct courses online between the spring and the fall. So I didn’t have a whole lot of time to think hard about what I was doing in any one of them. Just keeping track of what I had finished and what I had just thought about took multiple “to-do” spreadsheets. So that’s part of it: feeling like it’s the first time I’ve ever taught, and it’s all too much.

But there’s something else, too, something more fundamental. I’m missing the “Aha!” moments. When I teach in person, much of the time is spent moving around the room, listening to conversations, and nudging students to think differently or ask different questions. Most of the “lecture” time is spent answering questions and having wide-ranging discussions sparked by the material. At least once in every class period, some student would say, “Ooooohhhh!” or “Aha! I get it now!” as we finally figured out where they had gone off track, or what misconception they held without knowing it.

I miss that. It turns out that those “Aha!” moments were a primary motivator for me, as a teacher. That’s where I found joy. More than once, I’ve told friends, “If this is what teaching was when I started, I never would have done it at all. I would’ve been an engineer, instead.”

Well, so...enough complaining. Nobody would have asked for a giant global pandemic. What can I do about it? I’ve poked around a little bit, looking at “best practices” for student engagement in online courses and haven’t found my own “Aha!” yet about how to find what I’m seeking. I’ve had a couple of thoughts, but Im still mulling over the direction I want to go.

I have discussions open in Canvas every week and have managed to mostly respond to comments posted in those discussions, but students generally don’t respond to my responses. These are “graded,” but I set them up to be, fundamentally, a participation grade. In Astro101, I’m using open-ended “What If?” questions to spark discussion, and students do occasionally talk to one another there. In other classes, I’ve made them prompts about their struggles with assignments; however, students rarely comment on those. Going forward, I can modify these discussion prompts and grading practices for the upcoming semester to see if I can make them more useful but not onerous.

I’ve been available for students in my Zoom-room 15 hours a week, and I often have students drop in for a minute or two to ask a specific question (or I have students from the Physics with Calculus lab who stay signed in for three hours while they work through the lab and occasionally ask me questions). But much of the time, I’m doing other things—like grading, or chasing down why my Kaltura links are broken—while the box in the corner of my computer screen stays empty. I could make some of those times into synchronous instruction, or make it required for students to drop in and talk to me. But I hesitate because some of my students are already so stretched…so I’m not sure about it.

I’m still thinking about this problem, and I welcome ideas from professors who’ve taught online before. What practices are you using to help stay connected to the things that bring you joy in your teaching? I’d love to hear about them in the “Comments” section below!


Reading Astronomy News: Betelgeuse Might Be 25% Closer Than Previously Believed

By Stacy Palen

This week, I draw your attention to this piece of news that neatly encapsulates many of the concepts that you might be teaching at this point in the semester! Betelgeuse’s recent variability may be caused by dust and pulsation—so no nearby supernova in the works for us this year. That’s typical 2020 for you right there. Disappointing, all around.

Below are some questions to ask your students based on this article.

1) Why were astronomers, earlier in the year, talking about Betelgeuse exploding as a supernova sometime soon?

Answer: Because it had abruptly become dimmer, and evolution to supernova was one possible explanation.

2. What key conclusion in this most recent study definitively rules out the supernova-soon scenario?

Answer: Betelgeuse is still fusing helium in its core, which means that it has a significant amount of time left before it makes the full, onion-like set of fusion shells that precede a supernova.

3) Typically, astronomers first determine the distance to a star and then infer its size from knowing something about its evolutionary state and where it sits on the H-R Diagram. What did astronomers do differently in this study?

Answer: In this study, astronomers used stellar seismology to find the size of the star first and then worked backwards to determine the distance. This distance agrees (it is within the error bars) with previously determined distances to Betelgeuse.

4) Will Betelgeuse eventually explode as a supernova (even if we don’t get to see it this year)?

Answer: Yes, because it is a red supergiant.

5) Will that affect life on Earth?

Answer: Probably not. It is too far away to have an impact on life on Earth, although it would become incredibly bright for a short time.


Classroom Resources: Zombies and Aliens

By Stacy Palen

Apropos of the last few posts by Ana Larson about online classes and cheating (Thanks, Ana!), this week, I’m working on my Astro101 midterm.

It’s important to state up front that I think the purpose of exams varies from course to course. In Astro101, I think the purpose of exams is to make students look back over the last several weeks and connect different concepts across the material. For Astro101, the review is the goal, as far as I’m concerned. Therefore, I design my exams to guide them to do that review in a fun and engaging new context. In contrast, in a different course, such as Physics with Calculus, I have other goals, and they really need that material to be quickly accessible and at their fingertips for the next course. I design those exams differently, and I ask them to do the review on their own and then take the exam.

Historically, my Astro101 exams are story exams. I plunk students down on desert islands or in zombie apocalypses or some other contrived (and not entirely realistic) situation, and ask them to solve astronomy puzzles in order to survive. They might need to be able to tell time by the phase of the Moon, or find out whether it’s before or after the vernal equinox by judging the position of the rising Sun against the (formerly determined) position of Orion’s belt. I’m always bemused that students tell me that they think these exams are fun and practical.

I give students several days to do them, because they really do need to read the question and then think about it for a while—in this particular class, I’m not interested in whether they can do things quickly. And they can use any resources they have except other people.

But the things that I really like about these exams is that they are:

  1. Motivating: Students want to figure them out for themselves…because how could they ever know if they could survive the zombie apocalypse otherwise?!
  2. Fun: Students like to take them. Truly. They talk about them to their friends, and I usually get questions on the first day of class about whether I’m going to do this kind of exam again. Sometimes, even in other courses, if a student took Astro101 with me, they’ll ask if we are going to have fun exams or normal exams.”
  3. Fast to Grade: I have students draw pictures to answer a lot of the questions, which I can then grade out of a scale of three in less than a few seconds. For example, if the answer is first quarter, the Moon, Earth, and Sun are present and in the right orientation (3); they are all there, but drawn for third quarter (2); they are not all there or are in a completely different orientation, but they still drew something (1); or they did not answer the question at all (0). It typically takes me a full day (8-10 hours) to grade 120 exam papers because these picture questions take virtually no time to grade.
  4. Easy to Change, from One Semester to the Next: For example, I give them some data about the altitude of Polaris and ask whether they need to go north or south to reach a certain point. I can change that altitude, and people who are looking up answers online will not notice. So if I get last semester’s answer, I know to separate that exam to a different pile for…careful study. Or maybe they notice that this year it’s different. But to know why that difference matters, and give the correct answer, requires processing the material. And that meets my goal.
  5. Difficult to Cheat, Given My Goals: If I make them draw pictures in their own hand, then at some point, the information went through their brain, so some of it will stick. I’m satisfied because it meets my goal that they need to review the material and apply it in a new context. Because that’s my goal, I’m not bothered about how they go about it.

This semester, I hesitated all weekend about whether to send them the zombie apocalypse midterm. It seemed…insensitive, maybe…or just too stressfully close to reality. But then I made a joke of it, instead: It’s 2020of course there will be zombie apocalypse! I bet they LOL and dive right in.


Classroom Stories: How to Handle Cheating in Online Courses: Part 3

By Ana Larson

Ana Larson, co-author of the Learning Astronomy by Doing Astronomy workbook, gives us one last post about how to reduce cheating in online courses. 

To discourage academic cheating at the start of each quarter of my online courses at Seattle Central College, I started with an assignment where students had to complete a graded quiz (multiple takes permitted) on the content of the course syllabus and the policies and procedures of the college. Extra emphasis was given on the college's honor code and what, exactly, cheating included. My syllabus included explicit examples of what constitutes plagiarism and the consequences when unreferenced direct sources are used. In the last 5 years or so, students could use up to 3 outside sources, but those outside sources needed to be properly referenced using correct MLA or APA format. Students were given examples and helpful web links to show them how to do this.

Every quarter, there were at least 3-4 students in my course who lacked even the basic study skills. I envisioned them reaching a conceptually difficult concept, and rather than taking the time needed in a quiet, dedicated study area, immersing themselves in social media, texting, playing games, and cheating to find the answers. How are we supposed to teach study skills as well as astronomy? What if our departments require a definite amount of material that we are required to cover each term? Holy macaroni! We have families, other responsibilities, places we need to be, and people we must meet! It was frustrating to me that I spent a lot more time with some students and disproportionately less with the rest.

Unfortunately, over the 20-plus years I taught at the college, I did not keep records of the number of students who cheated, how they cheated, or whether (if any) a change in my policies or procedures made a difference. The course enrollment was limited to 30 students. Out of the number enrolled on the first day of class, usually 20-24 students completed the course. Those students included late registrations to replace students who dropped, complicating what would already be small-number statistics.

Fortunately, there are formal studies on academic cheating to which we can refer. I've mentioned the book Cheating Lessons: Learning from Academic Dishonesty by James M. Lang (Harvard University Press, 2013), which is an informative source covering various aspects of how students cheat and case studies of instructors who were able to reduce cheating and improve overall student performance. I recommend this book as he also brings in research from many instructors noted for their expertise and excellence in teaching.

The 4 features of a learning environment that may pressure students to resort to cheating are [1]: 

  1. An emphasis on performance
  2. High stakes riding on the outcome
  3. An extrinsic motivation for success
  4. A low expectation of success

With an emphasis on performance, students just need to demonstrate that they know the right answer at a certain time. A common example of high-stakes pressure is an exam or assessment that determines a major fraction of a student's grade. When an extrinsic motivation for success came from parents who placed a much higher priority on good grades than students, those students were more likely to cheat [2]. Most, if not all, of us have had students who believe that they cannot "do" math or science. They have not been successful in the past and thus carry a low expectation of success in astronomy. If students need a natural world or quantitative analysis course for their majors, they might just do everything possible to pass.

These considerations would seem to involve modifying our course content while simultaneously trying to survive the transfer of our in-person courses to online settings! During my two decades of teaching online courses, I had two main goals for making changes each quarter: 1) reduce cheating and improve learning through increased intrinsic student motivation, and 2) keep myself from becoming bored or complacent with the syllabus.

Let's start with increasing the intrinsic motivation for learning astronomy. Bring in a graded discussion forum for each lesson that has students comment on something current and related to the lesson. For example, news about potentially hazardous asteroids can cover telescopes, orbits, life on Earth, and so much more. How do we use Kepler's and Newton's laws to track these objects? I have also used the web-research topics given in Stacy's textbooks. If students can see the connection between astronomy and how it relates to what they already know or have read about, their personal motivation to learn should increase [3].

How might we move from grading a student's performance in a class versus assessing their mastery of the concepts? We don't keep what we want them to learn a secret. What are the learning goals for the lesson? For which learning goals will students need to have advance preparation for the assignment? How do we give them that preparation? We make sure that the assignment teaches to those learning objectives, whether they are broad or narrow in scope. Our quizzes and exams then bring in questions that directly assess their learning. At the start of each term, give students examples of how a learning goal leads to assessing their learning. I have had students request study guides for midterms and finals. My response: You already have that in the learning goals for each lesson. "You mean we need to study only that material?" (Well, yes, and the topics we've covered related to those goals.)

Consider lowering the weight of exams in order to reduce students' inherent stress in taking them. How often have we heard: "I don't test well”? Some instructors lower the stakes by giving multiple quizzes in order to drop one or more low scores. Another instructor might make a final exam optional or one that would only count if it increased a student's grade. This works if students have had a number of assignments over each term. In my online course, students had multiple assignments each week: a discussion post, a web-research assignment, a pre-activity quiz, an activity (from Learning Astronomy by Doing Astronomy), and a post-activity quiz. The discussions and web-research assignments were easy to grade because the guidelines given were clearly stated. The quizzes were multiple-choice, leaving the weekly activity for "line-item" grading. Since each lesson was structured the same, students (especially those new to online learning) gained practice in transferring learned skills to the increasing complexity of topics in a typical astronomy textbook.

From the research, Lang summarized: "The more times we test students in their recall of our course material, the more we are helping them learn it." [4] (The Lowering Stakes chapter pushes against a lot of preconceptions we might have on how students learn.)

Lang brings in research that states we should use formative assessment during our teaching. This involves brief, low-stakes activities that students do so that they and their instructors get feedback about levels of understanding. For in-class courses, these involve think-pair-share activities, minute papers, and clicker questions [5]. For online courses, these could be incorporated by using student groups or a dedicated discussion forum. The Learning Astronomy by Doing Astronomy workbook has associated pre- and post-activity quizzes for each activity. My solution, in addition to the multiple assignments and structured lessons, was to spend a lot more time in emails with these students and in answering specific questions they had about parts of an activity before they submitted it. There were cases where deadlines were extended and students resubmitted assignments. This was possible because the classes had less than 30 students. I have no answers for those online classes that have more than 50 students and welcome all suggestions and stories!

[1] Lang, James. Cheating Lessons: Learning from Academic Dishonesty. Harvard University Press, 2013. Print, p. 35

[2] Ibid., p. 46

[3] Ibid., p. 63

[4] Ibid., p. 114

[5] Ibid., p. 131


Classroom Stories: How to Handle Cheating in Online Courses: Part 2

By Ana Larson

Ana Larson, co-author of the Learning Astronomy by Doing Astronomy workbook, returns this week to discuss cheating in online courses. 

Those of us who have taught introductory astronomy in a classroom are quite aware of the number of ways students can cheat (a one-word catch-all for "academic dishonesty"). None of us should be surprised that teaching courses either partially or totally online brings in even more ways. The easiest to catch were those that were not in the student's own words. A quick search on the Internet using part or all of the question text would reveal the source. Here I cover one of the Internet sources (there are multiple similar sources online) for student plagiarism that I discovered in my Seattle Central College (SCC) introductory astronomy course, and the actions I took to deter students from cheating.

Under my policies, the first time a student's cheating was discovered, they got a 0 for that question. If they did it again, for even just 1 question without a citation, they got a 0 for the whole assignment. Since I wanted them to learn the material, which required doing the activity correctly on their own, I allowed these students to resubmit the assignment for at least partial credit. Students attending open enrollment colleges and universities can face personal, family, work, insufficient academic preparedness, and other challenges that interfere with assignment deadlines. With a few exceptions, students appreciated this additional opportunity to do well in the course, a two-way dialog was started, and their motivation for learning and doing well in the course seemed to increase.

Being a co-author of the Learning Astronomy by Doing Astronomy lecture workbook, I had the opportunity to use some of the activities starting in ~2017. By autumn quarter, 2019, I had put together a curriculum that successfully had these online students using all of the features of 10 activities found in the 2nd edition workbook.

By better preparing students for the activity, I felt that students would be less inclined to cheat. (Small number statistics precludes any conclusion, however.) I include a partial autumn quarter 2019 syllabus at the end of this blog.

Most of the students submitted multiple-page images for each activity through Canvas. Over the ~2 years of using the 2nd ed. activities, there were at least 2-4 students (out of an average of 22 students per quarter) who cheated by plagiarizing Internet sources. For me, the most distressing examples of plagiarizing involved students sending in images of complete pages of the workbook to Chegg.com and asking for "help." There were at least 3 "experts" who answered every question for students who submitted pages. Students would then use those answers verbatim.

Something you might consider: I ended up subscribing to Chegg.com over a few quarters in order to have access to all answers. There was a fee, but access saved me time overall, and I was better informed during discussions with students about how problematic this use of the Internet was. Plus, students recognized their instructor was Internet savvy! I then allowed students to resubmit their assignments.

While conducting some independent research, I found a question posed on Quora.com and particularly liked this answer to "Is Chegg cheating?" by Jiří Lebl:

Mostly, yes (it is cheating and you shouldn’t do it). It is also the worst way to study. At least in mathematics (I teach mathematics), homework assignments are exactly that. Exercises. Using Chegg is like going to the gym to watch other people exercise. Actually worse, you are paying other people to exercise in front of you and then telling other people you have exercised.

What drove my efforts to combat this behavior over all quarters was the possibility that students would encourage others to sign up for my online course because they were able to cheat without getting caught. Maybe saying, "I got a good grade and didn't even have to try!" Fortunately, no student ever implied anything close to this based on teaching evaluations.

There is action being taken to reduce this cheating at some of the very-top-needed levels! Reading these documents gave me hope, and I strongly recommend them to you as well.

In order to deter students from cheating in my own course, I use the syllabus as a contract for learning and include language that emphasizes the risks that come with cheating. Here’s a partial sample of my online course syllabus at SCC for Winter, 2020:

Astronomy 100 0L - Syllabus -Winter 2020 QUARTER

You should consider the syllabus for this course as your contract for learning. I will uphold my end and I expect each of you to adhere to course policies and procedures in addition to those set forth by Seattle Central College.

Academic Integrity
By participating in this course, you have agreed to the following: "Academic integrity is a basic guiding principle for all academic activity at Seattle Central Community College, allowing the pursuit of scholarly activity in an open, honest, and responsible manner. In accordance with the College's Code of Conduct, I will practice integrity in regard to all academic assignments. I will not engage in or tolerate acts of falsification, misrepresentation or deception because such acts of dishonesty violate the fundamental ethical principles of the College community and compromise the worth of work completed by others."

PLUS: It is expressly forbidden under the honor code of Seattle Central College for students to extract information from the Internet without proper referencing, claiming it as their own.  When a student plagiarizes, I give a 0 for that assignment.  I will be reporting the dishonesty to the eLearning office unless the student can give me a good reason why I should not.  I will be examining that student's answers very carefully in all future assignments and it is quite likely that that student will simply fail the course if he or she does not actually answer questions with their own words.

Mon Feb 24, 2020 Assignment Lesson 07: Discussion - A cross-section of humans versus a cluster or birth of stars due by 11:59pm

Wed Feb 26, 2020 Assignment Lesson 07: Web Research - Planetary Nebulae and White Dwarfs in the News due by 11:59pm

Thu Feb 27, 2020 Assignment Lesson 07: Activity - Preparation and Math Review Quiz 7 due by 11:59pm

Fri Feb 28, 2020 Assignment Lesson 07: Activity - Determining the Ages of Star Clusters due by 11:59pm

With each assignment, students also had to agree to the following: "The answers provided here are mine alone unless otherwise referenced." Combined with the language in the syllabus, this served as a successful deterrent for the most part, but a few students would still take the chance each quarter.

The assignments listed here for Lesson 7 were typical for each lesson. Spacing the assignments over the course of a few days each week helped me identify which students were procrastinating and needed nudges. The preparation and math review quizzes were the pre-activity questions from the 2nd edition of the workbook. The questions were multiple choice, and students could take each quiz twice. Students were given a 3-day grace period for turning in assignments, without penalty.

We can't overemphasize the importance of making it clear to students (and checking that each student understands) what our policies are when the school's honor code is broken. Find out what the policies for cheating are in your department and college. Hopefully you are not left to make policies on your own and are also free to add personal requirements.


Classroom Stories: How to Handle Cheating in Online Courses

By Ana Larson

This week, we have a guest post by Ana Larson, co-author of the Learning Astronomy by Doing Astronomy workbook, from the University of Washington. 

First, an introduction: twenty-two years ago (1998), as adjunct faculty, I developed an online course for Seattle Central College (SCC), which was Seattle Central Community College (SCCC) at the time. Online courses were just starting to become more available, and the learning management systems (LMS) were quite rudimentary compared to what we have today. I taught the online Astronomy 101 every quarter, every year, up until the 2020 Spring quarter, which is when enrollment at the college dropped.

In addition to required textbook reading, this online course consisted of three assignments each week: posting to a graded discussion board (and responding to other posts), a web research essay, and a lab-like assignment. As the years passed and the LMS became more sophisticated and included many more options for instructors and students, I added tutorials and short quizzes to prepare students for these assignments. 

This past decade has seen greater numbers of students enrolling in online courses, becoming better at self-motivation, and getting assignments in on time. However, there have always been those students, roughly 10-20 percent of the class, who just did not want to do the steps needed to learn the material. 

At first, this took the form of plagiarizing content from the Internet, primarily Wikipedia, but other sources were used as well. These instances were fairly easy to catch because the wording of the answers was obviously not in the student's voice. In these early days, some students copied and pasted material directly, including the links to other websites! Over the past few years, however, cheating has been harder and harder to catch, due mainly to websites like CourseHero and Chegg.

In an effort to help you discourage cheating in your own online/hybrid classrooms, I've listed my three best practices to discourage cheating in my online course below:

1) Give explicit information: The very first assignment that students had to submit was a graded quiz on the content of the course syllabus and the policies and procedures of the college. Extra emphasis was given on the college's honor code and on what, exactly, cheating included. My syllabi included explicit examples of what constituted plagiarism and the consequences when unreferenced direct sources were used. In the last five years or so, students could use up to three outside sources, but those outside sources needed to be properly referenced using correct MLA or APA format. Students were given examples and helpful web links.

2) State consequences: Students were told that they could get a 0 on an entire assignment even if only one answer involved plagiarism, which was the most common way of cheating in the course. I also outlined what was acceptable when students worked together, which I encouraged. In practice, if students were working on an early assignment and only a few of their answers involved cheating, I gave 0s for only those answers, with the caveat that any future instances would result in a 0 for the entire assignment. 

3) Immediately follow up: I interacted directly with students via course email and discussed why they got the grade they did. Most of the time, students were allowed to resubmit the assignment. I can think of only one or two examples where students did not respond to an email and continued plagiarizing. Those students failed the course.

Cheating is always upsetting, in any course, but in Astronomy 101, we have a unique opportunity to redirect students who cheat "by accident" by giving them the benefit of learning these important lessons without suffering from long-term consequences.


Classroom Stories: T-5...

By Stacy Palen

This fall feels weird. Really, really weird. Watching the pandemic erupt at higher-education institutions all around the country has filled me with anxiety: for my students, for my colleagues, and for myself. I feel very lucky that my University is primarily a commuter campus, so we are insulated from at least some of the pressures that are occurring at other places.

These are emergency times, and so I try to remember to be a little kind to myself. I’ve learned at least eight new kinds of software and picked up rudimentary skills in half a dozen fields that I never expected to need, like music editing and network maintenance. I don’t feel competent at any of it, but it’s unreasonable to expect that of myself. I’ve had just a few months of self-directed learning…in the middle of a global pandemic and civil unrest.

In times like these, it can be really hard to pick up your head and look forward to the “after-time.” But there will be a time after COVID. And I’m already finding things that I want to pull through into that time. Zoom office hours, for example. Would I have ever bothered to learn how to do that if not for the pandemic? Now that I’m setting up office hours for my students, it strikes me as an obvious thing that I will want to do for all my non-traditional, commuter students in the “after-time.” An introductory video to post to Canvas before class begins every semester is also a good idea, even for a face-to-face class! And weekly discussions, where students can ask and answer questions about the topics of the week—these don’t have to be confined to class time. I’m embarrassed that I never thought about these things before…but I was busy. Teaching.

This week, I am polishing up my “prep” on six courses to teach online for the first time in my life. (SIX! Yikes! Our enrollment is through the roof…we are all teaching overload…) I anticipate that next week, there will be some “fires.” Lots of things will not go as planned. Lots of things that seem like great ideas now will seem incredibly naïve later. It’s important for me to recognize that there are a whole lot of things that I have no control over at all.

We’ll see how all of this goes. I have been telling our students (in the introductory videos) that we are having ADVENTURES. As I write this, I am five days out from the first day of the semester. It feels very much like waiting for a rocket launch, with the same kind of hopeful uncertainty. I’ve done as much preparing as I possibly can. Now I just have to push the button and see what happens.

Best of luck to all of you. I hope you find some time to reflect, as you go along, about things that you will want to keep doing in the “after-time.” I’m sure there will be lots of great papers to write, about online teaching and learning, after the emergency is over. I look forward to reading all of them, and writing some of them.


Reading Astronomy News: The Mystery of Titan’s Expanding Orbit

By Stacy Palen

Titan’s orbit is growing, which is unexpected! This article might be appropriate when discussing orbits, outer planet moons, or resonances.

Below are some questions to ask your students based on this article.

1) What did astronomers EXPECT to find out about Titan’s orbit, before undertaking this study?

Answer: They expected to see that Titan’s orbit was unchanging.

2) How much does Titan’s orbit grow each year? Give an example of a common, everyday object that is about that size.

Answer: 11 centimeters (cm). This is a little bit shorter than a pen or pencil, so each year, Titan’s orbit grows by less than a pencil length.

3) Compare this rate to the rate at which the orbit of Earth’s Moon grows. Is Titan moving away from Saturn faster or slower than the Moon moves away from Earth?

Answer: The Moon moves away at 4 cm per year. Titan moves away from Saturn almost three times faster.

4) For how many years did the Cassini spacecraft orbit Saturn?

Answer: Cassini orbited from 2004 to 2017, so approximately 13 years.

5) During that time, how much did Titan’s orbit expand in total?

Answer: 11 cm times 13 years is 143 cm, just shy of 1.5 meters.

6) The semi-major axis of Titan’s orbit is 1,221,870,000 meters. By about what fraction did this value grow during Cassini’s visit to Saturn?

Answer: 1.43 m / 1.22187 X 109 m is about 1 in a billion. Dang.

7) What is “resonance-locking tidal theory?” How does this account for the loss of energy from Titan’s orbit, due to the orbit growing larger?

Answer: This is the idea that if the moon tidally flexes Saturn, in resonance with Saturn’s internal ringing, energy can be transferred from the moon’s orbit to Saturn’s internal motion.

What other questions would you ask your students based on this article? Feel free to leave suggestions in the comments!


Classroom Resources: Using the Workbook in the Online Class: A Plan

By Stacy Palen

Typically, in a F2F class, I use the workbook one day per week. In general, I do this on Friday. For each workbook activity, I’ll usually spend about five to ten minutes introducing the topic and pointing out places where students might get stuck or need a reminder. My astronomy course for fall is not synchronous, so I don’t expect that students will be logged in and working together, or that they will all be working on the activity at the same time.

I truly believe that these learning-by-doing experiences are critical to student learning. We’ve all had the experience of thinking we understood the material until we tried to actually apply it! The workbook exercises are designed with typical student difficulties in mind…so how do I do activities online, when students will likely be working alone, and I won’t be there to help them?

The first thing I need for each activity is a video mini-lecture that students can watch before they begin. I can address the same issues here that I would ordinarily address in the first few minutes of class. If I manage to keep it extra-short, like two minutes, they might even watch it more than once as they work their way through the activity and answer their own questions! I’ve begun creating these videos for the activities I’ll be using this fall, and I’ve shared the first one with you here so that you can take a look and see if it is useful to you.

I plan to set up weekly student hours in Canvas. These are times when students can arrange an “appointlet” with me. (That’s a new word, apparently, for the quick, five-minute interventions on Zoom or similar.) I am using the same time blocks for all of my classes. Still on my To-Do list is learning to use the scheduler in Canvas to see if that has all the functions I need.

Finally, each week, I will open a Discussion thread about the workbook activity due that Friday. This is a place where I can make note of things students found confusing and where students can ask questions.

Students will take pictures of their lab and submit it as a PDF in Canvas. There are a number of free apps that students can use to do this. I’ll grade the submissions in Canvas on my iPad. (Not to sell you on this particular set of products; others probably work similarly!) I’ve been doing this with upper-division assignments for a while now, so I don’t think that it will take me more time than usual to grade their work. In the first week, I expect to do a LOT of tech support.

At least I have a plan now. I don’t expect it to entirely survive the first few weeks of class. As Dwight Eisenhower famously said, “Plans are nothing, but planning is everything.” I’m trying to keep that in mind as we approach the fall semester. I’m sure you are, too!


Classroom Resources: Teaching with Videos: Textbook Chapter Introductions

By Stacy Palen

As I think about what I usually do in lecture, in order to try to capture some of it for the online experience, a few book-related things come to mind. There are a few things I do for each chapter, as general practice:

  • I provide students with an overview of each chapter.
  • I guide students to focus on what I think are the most important points.
  • I spend time orienting them to complicated figures.

All three of these things can be done in a video mini-lecture that students can watch before they read the text. To be clear, watching the video is not a replacement for reading the text. It’s just a way to lead them into the material.

I’ve started preparing five-minute video introductions to each of the chapters in Understanding Our Universe, Third Edition. These introductions page through the chapter, highlighting the text and figures that students should pay special attention to, because I know they will come up again. For example, I know that the cosmological principle will be referenced multiple times throughout the book. So, in the Chapter 1 video, I make students aware that they should pay special attention to that concept.

The first two videos, for Chapter 1 and Chapter 2, are linked.

Let me know what you think, and if you find these resources useful! Like all of you, I’m working away in my office here, trying to anticipate the coming semester as much as possible. I suspect that “Future Stacy” will be very grateful to “Past Stacy” if I can get some things prepared now and free up some time during the semester itself.