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Venus in August 2018 August 1, 2018

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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Everyone else may be talking about Mars, but don’t miss your chance to check out Venus this month!

 

The orbits of Earth, Venus, and Mercury about the Sun, with 16º elongation and maximum eastern and western elongation shown.
The maximum elongations for Venus are shown with the dashed lines, and those for Mercury are shown with the dotted lines.

Venus orbits closer to the Sun than we do. That means from our point of view, it never gets very far from the Sun. When it is farthest in the sky from the Sun, we call it greatest elongation. On August 18, Venus will be at greatest eastern elongation, and it’ll be a little over 45º east of the Sun. That means it’ll be easy to see in the western sky for at least an hour after sunset.

 

 

Additionally, Venus will be headed for a crescent phase, which brings it closer to us, so it’ll be getting bigger and brighter. It’ll actually be at it’s brightest near the end of September.

 

 

Because of the angle of the ecliptic, it sets a lot sooner in September. Here are a couple maps showing the ecliptic from SE Michigan (or anywhere between 40 – 50º N latitude) on August 1st and 30th, both 1 hour after sunset. You can see the ecliptic moves southward, which means anything on the ecliptic will set earlier in the northern hemisphere.

W (west) is at the center bottom and NW near the bottom right corner. The ecliptic runs from the top left corner to the bottom about 1/4 of the way between W and NW.

Venus and the ecliptic on August 1st 2018, 1 hour after sunset.

W (west) is at the center bottom and NW near the bottom right corner. The ecliptic runs from the top left corner to the bottom just to the left of W.

Venus and the ecliptic on August 30th 2018, 1 hour after sunset.

So now’s the time for the easiest and latest observations of Venus, and September will be the time for the brightest and most interesting telescopic view of Venus!

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Observing tips for July 4th, 2018 July 2, 2018

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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The forth of July brings a lot of people outside after dark. While you’re waiting for those fireworks to begin, here are a few things to look for.

I recommend taking along a pair of binoculars.

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Venus and Mercury in the West July 3, 2018, 9:30 PM.

Start about half an hour after sunset (or about 9:30 in SE Michigan) and look west. About 20º ( 2 sideways fists) above due west is Venus. As the skies darken, it stands out like a beacon! look 16º (index finger to pinky) down and to the right for Mercury. Mercury can be a tough object to spot because it’s never far from the Sun, so it’s never visible in really dark skies. The first map is for July 3, 9:30 PM in Ann Arbor, but should be good for the 4th as well.

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Jupiter and Saturn in the south at 10 PM July 4

Fireworks usually begin around 10 PM (especially if you’re farther north.) Get a seat facing south for some of the summer’s best celestial show. Jupiter is about 30º above the southern horizon, and Saturn about 10º up in the SE. While you’re looking that way, be sure to check out Scorpio and Sagittarius too. Bright Antares, the heart of the scorpion, falls between Jupiter and Saturn right now.

With binoculars or a small telescope, you can pull in the 4 brightest moons of Jupiter. They’ll be lined up in a tight row on the 4th, which helps make it easier to pick them out at low magnification.

From left to right, Io, Europa, Jupiter, Ganymede, and Callisto

The Galilean Moons of Jupiter at 10 PM July 4, 2018.

If you actually have a small telescope and can pull your eye away from Jupiter, check out nearby Zubenelgenubi, a nice double star whose name means “southern claw” because it was once considered part of Scorpius.

Saturn is sitting on the top of the teapot. If your skies are dark enough later in the evening, you’ll be able to see the Milky Way trailing up the sky next to it. With binoculars or a small scope, the rings should be visible, if only as a strangely oblong shape. Some of the brighter moons may also be visible, though they aren’t nearly as easy as Jupiter’s moons.

From left to right, Iapetus, Rhea, Saturn, Tethys, and Titan, which is actually much lower that the other moons.

Saturn and its moons, July 4, 2018 at 10 pm

It’s early days yet for Mars, but if you’re out past midnight, look back to the same are Saturn was at 10 PM. Mars rises ESE around 11 PM, so it’s up nearly 10º in the SE at midnight. It’s the brightest thing in that area right now, and only getting brighter, so if your skies are clear, it’ll be hard to miss. Keep an eye on it the rest of the month as it moves toward closest approach on July 31!

ES2018 – Creative use of technology to assess students June 1, 2018

Posted by aquillam in teaching.
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Enriching Scholarship is an annual series of workshops on teaching and learning at the University of Michigan. This session was on technologies that could help with student assessment.

The session started with a discussion of what is assessment. We tend to think of it as a method of assigning scores/grades (summative assessment), but the discussion showed we really mean a lot more than that. In particular, gaging understanding, getting feedback and re-evaluation (formative assessment) were topics covered in the discussion.

There was a brief discussion of Universal Design for Learning (UDL) The idea behind UDL is that not everyone comes to the classroom with the same set of skills and concepts. If we consider the whys and hows of learning, and are intentional and explicit in our assignment design, we can mitigate disadvantages caused by differing backgrounds.  Generating engagement and providing multiple pathways to achieve flexible but well defined outcomes improves learning.

We then spent some time discussing what most people do for their classes. It was not particularly surprising that most people place a lot of emphasis on reading before class, and delivering lectures in class. These are very unidirectional, and don’t encourage engagement or deeper thinking. There are technologies that can help.

The presenter, Ebony Perouse-Harvey with CRLT, provided a handout with several resources. Here are some basics from that handout (with apologies that I didn’t take the time to copy down all the links):

  • Clickers and short response tools let you do quick checks of student understanding. Some can be used to take input from students, like allowing them to ask questions during lecture. these include iClicker, centimeter, piazza, poll Everywhere, and Google forms.
  • Word clouds can help you gage student’s exposure to subject mater and vocabulary, or topics of interest. They can also be useful in brainstorming.  Tools include Mentimeter and Poll Everywhere.
  • Mid/concept mapping help student make connections. (As a side note, I’ve looked into these before since one of the biggest problems for our labs is that students see each lab as an isolated activity, divorced from all the others and from the lecture. There are a lot of astronomy class mind maps on mindmeister and most of them are terrible. They tend to look like the table of contents to the text. Concept maps should be a powerful tool to help students make connections, like linking exoplanet discoveries back to line spectra, Kepler’s laws, and the Moons of Jupiter lab, but I haven’t seen a truly effective assignment.) Tools include bubble.us, mindMeister, and MindUp.
  • Google Docs / Canvas Collaborations (Gogle Docs portal within Canvas) – collaborate tools like text documents, spreadsheets, or presentations. This requires a whole different blog post…
  • Discussions offers threaded communication between peers or between the instructor and student. The Canvas discussion tool can be set up to have threads available to the whole class, and other threads available only to a group. Piazza also offers anonymous posting.
  • Blogging can be used to capture student ideas during a class session.

ES 2018 – effective group assignments May 31, 2018

Posted by aquillam in teaching.
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Enriching Scholarship is an annual series of workshops on teaching and learning at the University of Michigan. This session was on creating effective group assignments.

Research shows that group work increases students’ perceptions of learning and their belief in their ability to learn, improves retention of information, increases learning of higher-order tasks, and improves scores. Additionally, more diverse groups usually work better than less diverse groups, both in terms of group outcome and individual success. Students are often resistant to group work, so it’s important to include your reasoning for requiring group work and the references in your syllabus or instructions. References were provided in this session, but only on a printed sheet.

Creating effective group assignments actually depends on two things: a good assignment and a good group. If you’re also using the assignment for assessment, you’ll also need a mechanism to evaluate the work.

Creating a good assignment

There are a couple elements to consider before creating your assignment.

The first is to make sure the assignment aligns with your learning goals. As you develop the assignment, be sure to go back and reassess whether or not the tasks still lead to that learning goal. It is best make the learning goal explicit in the assignment as well so that students know it isn’t just “busy work.” Students often don’t make connections between different aspects without some guidance.

Make sure the assignment is appropriate for a group. If you give a group the assignment to do a reading summary, chances are one person will do the summary and they’ll turn it in for the group. Instead, have them compare summaries and come up with a list of things everyone had in common, and a list of things someone thought was important but others missed. If it’s a task the average student should be able to complete alone, it’s probably not a good group task. Tasks that create interdependence are best, since they make group members reliant on each other.

Design assignments to promote higher-order cognitive skills. Again, lower level tasks like memorization are just as easy to do on your own. Group assignments provide the opportunity to test your thinking, uncover misconceptions or logical fallacies, and get different perspectives. Good assignments take advantage of those opportunities.

Good assignments usually have the following components

  • individual prep
  • a group task
  • outcome or deliverable
  • debrief

Generally, assignments are better if each of these is made explicit. Essentially, students need to know what the expectations are to perform well, and they are much more likely to develop a deeper level of learning if they are given the opportunity to think about it.

This is true even for small assignments. For example, you can give students a reading assignment (individual prep), with a think-pair-share activity in class (individual and group tasks). A flashcard or clicker response provides the outcome, then a class discussion about why students chose the responses they chose is the debrief. The syllabus should have formal instructions to students about the expectations of reading the material, working with peers, bringing a clicker/flashcard to class, and participation in in-class instruction. The debrief is an important aspect since it is the part that allows students to make sense of the answer. Without the debrief, students may not have an opportunity to do more than memorize the correct response. As long as you regularly practice these small or informal group assignments in class, the syllabus instructions are sufficient.

For larger assignments, the same guidelines still apply. The primary difference is that there are likely to be several stages with a different set of individual preparation and group tasks for each stage. Each stage may also have it’s own deliverable, separate from the final outcome or deliverable. It’s also important to debrief periodically to ensure all team members are meeting the expectations of both the instructor and their teammates. One of the reasons students are so resistant to teamwork is due to a bad experience in the past, where there were problems with a team that went unrecognized or unresolved.

Forming groups

Group formation depends heavily on the assignment. In general, it is better to have groups with some diversity in them, which usually means not allowing students to self-select groups. However, the assignment and group size affect this.

Small assignments with small groups, like think-pair-share in class questions, are generally fine with self selected groups. If nothing else, class time would be lost waiting for students to change seats. You can always ask students to sit in adjacent seats at the start of class, and have them turn to a different neighbor for each question.

Similarly, projects that extend thorough  a single class period but not beyond (e.g. a lab) are unlikely to benefit significantly over the time it takes to assign and organize groups. However, splitting up cliques and social groups may be beneficial. Randomly selected groups can often work well in these cases. For example, have students count off by the number of groups needed before starting on the activity (i.e. a class of 24 needs 6 groups, so students could off 1 – 6, then all 1s work together, 2s work together, etc.) Use caution with this approach. While diversity is good, you should be careful about isolating certain individuals. Students for whom English is a second language are especially at risk of isolation when placed in a group of native english speakers. Women, minorities, and those with physical or learning impairments can also be negatively impacted. You’ll have to weigh the effort of creating not-quite-random groups with the composition of your class.

Long term or major projects work best with carefully considered groups. In particular, the greatest gains are made when groups have heterogenous but not too dissimilar abilities. For example, putting a A student in with a B student forces the A student to explain, which can help clarify thinking and deepen understanding. The B student may gain strategies or insights from the A student. Similarly, a physics major can help the group understand the science, and an english major can help the group express their ideas clearly. When creating the groups, it’s important to try and match interests and motivation. If two of the four group members are deeply invested in the idea that Pluto is a planet, and the other two group members want to explore Mars, the group may not form a cohesive unit.

CATME Team generation software can be used to collect data on students and generate teams based on criteria you specify. It is NOT free, but you can contact ISS for resources to help cover the cost for a U-M course. As far as they know, this is the only software that can generate groups. You can also use Canvas surveys, Google forms, Qualtrics, SurveyMonkey, or other software to collect the data you want, then form the teams manually.

Any group that lasts more than a single class, and any assignment worth more than a minuscule amount  of credit, especially if it’s group credit, requires some form of group assessment and recourse for dysfunction. Assess early and often. You want to catch problems in time to correct them, not after the group implodes.

Assessing groups

When generating a score for group assignments, you want to measure both individual performance and group performance. This should include peer evaluation whenever possible, but keep in mind that teams of two will never have anonymity. Be sure share the assessment protocols at beginning of semester or assignment  (i.e. BE TRANSPARENT!) If you want honest evaluations, you need to employ non competitive grading. A rubric with options like “meets expectations” can be good, but you may want to consider requiring students to justify high or low responses. Evaluations should be goal oriented, so there are concrete outcomes to evaluate. Note some of the people in the session did have competitions, so the students could select things like “most visually appealing project” or “most helpful teammate”, but these did NOT enter into the assignment scores.

CATME includes peer evaluation tools and allows you to require both self evaluation and peer evaluation. Teammates is another full featured tool for peer evaluation and feedback. See http://teammatesv4.appspot.com/. There is also the peer evaluations in Canvas.

Take home points

  • assignments with meaningful interdependence foster student interaction
  • intentional structuring of teams promotes inclusion & learning
  • peer eval is a valuable skill and provides evidence to instructor about group dynamics