From plesser Wed Oct 9 22:56:52 2002 Return-Path: Received: (from plesser@localhost) by landau.cgtp.duke.edu (8.11.6/8.11.2) id g9A2ukw26395; Wed, 9 Oct 2002 22:56:46 -0400 Date: Wed, 9 Oct 2002 22:56:46 -0400 From: "M. Ronen Plesser" Message-Id: <200210100256.g9A2ukw26395@landau.cgtp.duke.edu> To: ek9@duke.edu, nl13@duke.edu, smp16@duke.edu Subject: Outreach program Cc: karenandjohn@earthlink.net Status: RO Hi Eileen, Nooree, and Shaama Thanks for volunteering to do this. Should be a lot of fun. As I said, there are three third-grade teachers who want us to help them teach the kids about moon phases, eclipses, etc. in preparation for the November eclipse. Tomorrow, Nooree and I will go to John Heffernan's class to start; friday Shaama and Eileen will go to Lisa Byrd's class and Joe Turecky's class. Here is the rough plan John and I came up with for the first t three meetings with them (once a week). Any comments or ideas on this, now or at any time, are most welcome. I think it is safe to say we are all just learning how to do this stuff. For now, I will coordinate with teachers to make sure all the stuff we need is available to us. 1. For the first meeting, we try to explain the way Earth's rotation causes Sun to move in sky, leading to night and day, and the fact that the time of day is different in different places on Earth. - First spend 30 minutes with a globe to represent Earth, an overhead projector representing the Sun, and a little figurine you can put on the Earth to represent people. Explain that a globe is a small-scale model of the Earth. Explain that in our pretend game for the day they are huge (bigger than Earth) and out in space. They can pretend they have spacesuits for air. But space is dark (turn off lights). Only light around here comes from Sun (turn on slide projector). If you look at Sun you get blinded, so don't. But when sunlight hits Earth, you can see the Earth. Moreover, people on Earth can now see stuff around them because sunlight illuminates it. But not all people on Earth. Note that only half of Earth illuminated. People on that half can see around them; if they look up (use figurine) they see the Sun. On other side of Earth, it's dark and Sun is not in sky. Let them tell you this is day/night. Now ask them how this situation changes. Get to Earth rotating slowly. Takes a whole day and night to go around - 24 hours. Show them Durham and go through a day and a night in Durham, showing where the Sun seems to be. Explain that Sun looks like it moves in sky - rises, sets, etc. - just as when on carousel things *off* the carousel seem to be spinning. Earth as a merry-go-round (you can tell them we move at 800 mph as it spins if you think it will not take you on a huge tangent). Finally, show how different places on Earth have a different time of day at any given time. If there are kids in the class who have flown far enough to notice (ask teacher about this in advance - it may be her opportunity to let some foreign student who never talks shine) let them talk about jetlag and explain how this works. - Following these (rather dense) 30 minutes they will do a follow-up activity with you and the teacher helping out and monitoring. This is likely to be a good group activity but how they do it is up to the teacher. We will hand out papers with several configurations of a Sun, an Earth (each a circle), with four points marked on Earth. One of these will be red and will represent Durham. Sun will always be on left (say) but Earth will be rotated, so time in Durham is different. Their first goal will be to color (in yellow?) side of Earth illuminated by Sun. Then they try to figure out if it is day or night in Durham. Then to guess what time it is in Durham. Finally, they can go back and try to figure out what time it is at the other points marked on Earth in each of the configurations. This should help nail the concepts. It will also come in handy later when we use the same trick to understand Moon phases. 2. Second weekly meeting we introduce Moon phases. - Start with a discussion of shapes the Moon takes in sky. Establish (they will likely have discussed this) that Moon itself does not change shape, rather it is a ball. Present a moon globe or some other ball to represent Moon today. Today, the students (sitting on carpet in a group) will be on Earth. Overhead, back in corner of room, will be Sun as usual. Show how moon shines by reflecting sunlight (it is not a star or something bright, just a lump of rock, rather like the globe we have here). Now, you have someone (teacher or me) man the overhead and keep it pointed at you (unlike Sun it does not illuminate all directions) as you move around students (who are playing Earth). At different points they should be able (if class is dark and overhead bright enough) to see differently-shaped Moons just as we do in the sky. Show then how looking at Moon tells us which way the Sun is (follow illuminated side!). So Moon's orbital motion around Earth creates phases. If you have time, integrate this with previous discussion of rotation - like Sun, Moon will rise and set; you can even try to point out relation between phase and moonrise/set time - both are determined by where in sky moon is relative to sun. Make sure they realise we can see Moon during the day! New Moon was 10/6 so moon rises in early pm this week, they may be able to see moon and sun in sky at the same time for a real picture to compare with our theory. - The follow-up activity here is a paper worksheet similar to the one used the first time, but the configurations will include Sun, Earth, and Moon. First they can color day/night onto Earth for warmup (depending on time). Then do same for Moon - color in yellow the region illuminated by the Sun. Now color in blue (use color pencils, I guess) the half we can see from Earth (opposite order?). Green overlap is part we see shining when we look at the moon. Note how size of this changes as Moon moves around Earth (Sun still always on left here!). Try to talk them through understanding how the little wedge on their circle becomes a crescent on a sphere. 3. Third meeting to reinforce the phases. - Activity here will involve each of them making a model moon with a styrofoam ball on a popsicle stick. They can paint a face or maria on one side. They then hold this out at arm's length in directional light (probably best to use sunlight if possible - if we use the overhead can only accomodate a few kids at a time). They turn around - insist this represents monthly moon motion, not daily rotation - holding toy moon in front of them, and notice (a) always see face, synchronous rotation (do not use that word), and more importantly (b) see different shapes illuminated - phases. - Follow up here by discussing the Moon charts they will have been keeping for about three weeks by this point. Compare what they saw in the sky with what we have discussed and try to tie it together. After we see how these three went and where we are on the calendar we will plan some more. The idea is certainly to discuss eclipses and how they do or do not happen. By November they need to understand what a penumbral lunar eclipse is (do you still remember this?) so they know what they are going to see (pray for clear skies!). We can also talk about annual motion of Earth, tilt of axis, seasons, why we see different stars etc. as the year goes on. Each of thesae should take about an hour. Plan time carefully and modify plan on your feet as you go, because both we and they have places to go at specified times! Try to find a minute to talk to teacher before or after to summarize how it went, what to tweak for next time, etc. Try to get them to exchange emails with you as that is a far better way to keep in touch with them.