Tag Archives: science projects

Walking to Pluto, Step 4

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Step 4:  Go Farther

Pluto & Charon in Full Color (Image Credit:  NASA)

Pluto & Charon in Full Color (Image Credit: NASA)

New Horizons has flown past Pluto successfully, and is now on the way to check out other Kuiper Belt objects.  Here’s Corwin Wray’s simulation (made with Pixel Gravity, his software for doing multi-body models on your laptop), which concludes with a wistful look back at our Solar System:


Like New Horizons, you can explore further too.

It’s worth your while to start by tracking down Guy Ottewell. Yes, he’s on the web, folks, and you can connect with him! Start with his Home Page, which includes all of his books, including the latest version of the book form of his Thousand-Yard Model as well as innovative ideas in several fields, from voting systems to landscape design:    He has a Facebook Page on which he’s been more active as of 2014, sharing art and world news:    And he joined Twitter in 2013 and tweets regularly, especially on human-rights topics, which should interest anyone who’s become aware of just how small our human community is in this huge universe: find him as simply @GuyOttewell on the tweet machine.  A few of his books are available at Amazon, but take care—the latest updates are best obtained by purchasing directly from the author.


Of course, you might want to follow some of informational links given in the workbook pdf’s for this project:

For more information on both the inner and outer planets: http://solarsystem.nasa.gov/planets/charchart.cfm

For more information on the asteroid belt:   http://solarsystem.nasa.gov/planets/profile.cfm?Object=Asteroids&Display=OverviewLong

For more on Kuiper-belt objects and Pluto:   http://solarsystem.nasa.gov/planets/profile.cfm?Object=KBOs and also http://solarsystem.nasa.gov/planets/profile.cfm?Object=Dwarf

And of course we have an active mission beyond Pluto right now.  It’s an APL project, so they have a great page on the program:  http://pluto.jhuapl.edu/

Read about the Pioneers’ adventures here http://www.nasa.gov/centers/ames/news/2013/pioneer11-40-years.html#.UzDJ44WwX_0 and here http://www.nasa.gov/topics/history/features/Pioneer_10_40th_Anniversary.html#.UzDKb4WwX_0

Discover more about the Voyager missions at: http://voyager.jpl.nasa.gov/where/index.html

And find out where all the system-leaving spacecraft—as well as Earth-orbiting satellites, the planets, and other system objects–are right now: http://www.heavens-above.com/SolarEscape.aspx?lat=0&lng=0&loc=Unspecified&alt=0&tz=UCT

For more on the Oort cloud, see http://solarsystem.nasa.gov/planets/profile.cfm?Object=KBOs


Lots of other interesting links:

The National Optical Astronomy Observatory presents Guy Ottewell’s original project description from 1989 online:

A wonderful collection of poems and quotes related to astronomy, gathered by Michele Stark, an astronomer with a wonderful page she created while lecturing in physics at the University of Michigan, Flint. l  You’ll also find astronomy labs she’s created for non-majors interested in the field, under “Outreach and Education

A relatively exhaustive listing of scale models in place around the world—most are designed for point-to-point driving or cycling tours, so scroll to the bottom portion of the list for walkable models, several of which are roughly on the same scale as that presented here. Check before you set out—some of these installations were only temporary, as part of larger events and some are virtual (i.e., online). I would like to imagine astronomy fans travelling to all of them, as baseball fans travel to all the major-league parks.

The National Center for Earth and Space Science’s “Voyage” program has a “somewhat” pricier scale model in Washington D.C. but also offers up lots of useful curriculum materials:   http://voyagesolarsystem.org/   Their program is fee-based, not by any means free, but it is very comprehensive and aims to involve parents, teachers, students, and their communities: http://journeythroughtheuniverse.org/home/home_default.html

You can keep track of the Voyager spacecraft in real time at http://voyager.jpl.nasa.gov/where/index.html   They’re in rapid motion—Voyager 1 is travelling at over 38 thousand miles per hour (over 17 km per second).

All about the sun (with a wonderful NASA graphic of a solar flare compared with the Earth): http://www.universetoday.com/94252/characteristics-of-the-sun/

A summary page on the Peppercorn Model at SpyHill Research, which also includes some links to interesting places: http://www.spy-hill.net/myers/peppercorn/

Why isn’t an AU exactly the same as Earth’s orbit any more? Sorry academics, the best answer is in Wikiland: http://en.wikipedia.org/wiki/Astronomical_unit

More about our Moon: http://www.universetoday.com/19677/diameter-of-the-moon/ By the way, Universe Today is a good site to follow!

Asteroid information for Wiki fans: http://en.wikipedia.org/wiki/Asteroid_belt

The Project Astro Notebook used to be sold as a huge expensive bulky (and still wonderful) binder. Soon, you’ll be able download at least some portions in pdf format from the free government-sponsored education resources site eric.gov. However, for now your best bet is to buy the DVD’s at http://astrosociety.org/astroshop/index.php?p=product&id=577&parent=1

While you are waiting for your DVD to arrive, the Astronomical Society of the Pacific has a page full of resources for you, including a few of the Project Astro activities. http://www.astrosociety.org/education/astronomy-resource-guides/

If you actually need to shop for marbles, by all means the best place for working on this project would be “Moon Marbles”, at http://www.moonmarble.com/c-78-shooters-approx-19mm-or-34.aspx

Astronomer Phil Plait summarizes the latest estimates on stars with planets beyond our own system: http://www.slate.com/blogs/bad_astronomy/2013/11/04/earth_like_exoplanets_planets_like_ours_may_be_very_common.html

Why use a FIFA 4 or 5 ball? Well, the dimensions are good for it. But any similar-sized ball will do for this project…like the tennis-ball-patterned playground ball I have.  Guy Ottewell likes to use a bowling ball—but notes that it’s kind of heavy to lug around. http://www.achallenge.com/t-faq.aspx

A seemingly unrelated topic—watching for the bright flare of reflected sunlight from certain Earth-orbiting satellites: http://www.washingtonpost.com/wp-srv/washtech/features/iridiumqa.htm The interviewer on that page is talking to Chris Peat, whose website contains a wealth of information on satellites, the solar system, and the positions of the Pioneer and Voyager spacecraft. http://www.heavens-above.com/?lat=0&lng=0&loc=Unspecified&alt=0&tz=UCT

Just to show how established walkable solar system models have become, here’s a typical promotion for a talk by Eric Myers of SUNY (see the GoogleMaps list below) and another talk summary that may inspire you to think about other ways of building a model https://nightsky.jpl.nasa.gov/event-view.cfm?Event_ID=44693   and http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0CGcQFjAG&url=http%3A%2F%2Fregionalaaptmeeting2013.weebly.com%2Fuploads%2F2%2F2%2F9%2F3%2F22939768%2Faapt_meeting.docx&ei=jaU5U5rvCqiIyAGK0YHwBw&usg=AFQjCNHl4_6jyF2UU_JJ7H9SrD6suXOhjA&sig2=MBKeDxFBGjHlVB2rk8n3wA&bvm=bv.63808443,d.aWc

A few places (courtesy of SpyHill Research’s page) where you can use GoogleMaps to follow a model:

> SUNY College at New Paltz, New York:  Map, KML

> Dutchess County Rail Trail, Morgan Lake, Poughkeepsie, New York:  Map, KML

> Riverfront City Park, Salem, Oregon:  Map, KML

> Walkway over the Hudson, between Poughkeepsie and Highland, NY:  Map, KML

> Marist College, Poughkeepsie, NY:  Map


For an insanely delicious solar-system project for any mad bakers in your circle, visit Rhiannon’s recipe on her cakecrumbs blog: http://cakecrumbs.me/2013/08/01/spherical-concentric-layer-cake-tutorial/ with some extra photos and video on waitwow http://www.waitwow.com/make-scientifically-accurate-cake-planets/

If you need more reassurance that science and math are not only fun but also funny, visit http://www.xkcd.com (but do prescreen before sharing with students—this webcomic does sometimes use “PG-13” language.

If you have already memorized all of Gary Larson’s Far Side comics, visit the science cartoon webring at http://jcdverha.home.xs4all.nl/scihum/webring.html

And of course, don’t forget to visit Science Cartoons Plus (http://www.sciencecartoonsplus.com/pages/gallery.php)


Materials shopping tips:

Pins with small round heads—look for beading pins—however, be aware that beading pins aren’t sharp, so pick up some ordinary pins as well. http://smile.amazon.com/Beadaholique-20-Piece-Ball-21-Gauge-1-5-Inch/dp/B00BBAXXYS/ref=sr_1_1?s=arts-crafts&ie=UTF8&qid=1396515591&sr=1-1&keywords=pins+2mm+head   For pin tips, any small sewing pin with a nice sharp tip will do. (Note that beading pins are not that sharp.)

For the jacks ball, you can pick up a jacks set anywhere. Online (e.g., www.orientaltrading.com , they’re often sold in party packs of a dozen sets. But any bouncy ball bigger than ¾” and no bigger than 1” in diameter will do the trick.

If you decide to buy a playground ball or soccer ball online, locate an air pump before your shipment arrives—they’re often shipped uninflated.

And if you buy on Amazon, be sure to sign up for smile.amazon.com first, so your purchases can support your favorite charity.

Chasing Comets: Supplies & Resources

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Chasing Comets

Supplies and Materials

Below, you’ll find a handy supply document you can download, with shopping lists for small and large groups and a range of cost estimates, depending on how much of the supplies you can acquire from available supplies or donations by participants.   With a minimal outlay, you and your group can experience being comet chasers–observers of comets.

Basically, you need a bunch of badminton birdies for your comet heads—keep in mind you don’t need performance-grade shuttlecocks or even new ones. If your high school has a badminton team, they will have worn-out birdies you can take off their hands.   A grungy, beat-up birdie makes a more realistic comet head.

Chasing Comets

Birdies for Comets

And you need a bunch of ribbon—curling ribbon for the comet tails. The supply sheet estimates ribbon packages at around $8, but if you look at this photo, you’ll see the last time I bought supplies, it was out of the clearance bin at $2. And if you can get one in five of your participants to bring in a roll to share, it won’t cost you a dime.

Chasing Comets

Zoom Out–Yes! Here’s All You Need To Make Comets

The one oddball item is that tulle fabric ribbon for the big comet. This you might have a hard time finding in your junk drawer unless you’ve been helping a bride make wedding tchochkes. But for $10 you can buy enough to make three huge comets. Cut five-yard lengths and tie one end of each to a vane of a single birdie, allowing a few inches of extra length to fan out as the comet’s “coma”. Tulle scrunches up easily, so even a six-inch-wide ribbon will feed through the holes between the birdie’s vanes.

Chasing Comets

Detail–How To Tie Fabric Tails

You should be able to borrow a portable fan and a playground or soccer ball. If you can’t, it will take a roughly $25 expenditure to get those items in stock—a cost you can recoup in part by either donating it to the group you’re working with or simply deducting the expense as part of your cost of volunteering.

And it is presumed you can find a pencil, which makes holding the small model a little easier when you’re doing the demo with the fan;  here’s the trick for hooking the pencil to the comet head:

Chasing Comets

Holder For Fan Experiment

Depending on how good you are at scrounging supplies and locating soccer balls, your costs will range from $10 to $85 for typical group sizes.   The spreadsheet I use has a calculation column to adjust the requirements list for other class sizes  So, if you want a copy of this  fully-functional workbook, “like” the Facebook page & I’ll send you one via a Facebook “message”. (You can also try emailing me through the “contacts” page here, but you’ll get a faster response on FB.)  Your FB contact will be used for nothing other than sending you a file and boosting the “likes”-count on my page.  [Insert maniacal laughter, if desired.]

Meanwhile, you can get the static workbook as a pdf right away:

Just Supplies Chasing Comets


Resources and References

Now that you are all excited about comets, here are some fun places to go where you can find more cometary material:

A lovely one-page summary from the Spaceguard Program (sponsored by the European Space Agency) gives a clear description of comet tail structure and dynamics, including a neat animation of what both tails look like as the comet proceeds around the sun. The ion tail streams straight back, while the dust tail is curved a bit as the particles within the dust tail blend movement due to their individual orbits about the sun and the forces of the radiation pressure. Net, both tails roughly point away from the sun, as in our demonstration.

Sweet page from NASA with helpful animations and clear descriptions.

Follow the European Space Agency’s comet-chasing spacecraft, Rosetta, as it aims for the first robotic landing on a cometary nucleus.

Read this:  a “real” science article with a good set of detailed discussions of the types of comet tails and how they work.

Or, try this excellent piece by freelance science writer Craig Freidenrich on the inner workings of comets.

The Swinburne Centre for Astrophysics and Supercomputing’s educational site helps with details on the structure of comets.

Explore a public-domain catalog of Solar System images, from Hubble and other spacefarers.

Discover how Oort clouds may be one way star systems interact directly with one another, because the Oort clouds project so far out.

See the invisible part of a comet.

Find out all about radiation pressure.

Plan to catch sight of the meteor shower sponsored by Comet Halley.

Explore the origins of comets at this UC Berkeley site.

Check out NASA’s solar system photo gallery, with images from NASA and European Space Agency exploration missions and telescopes.

Visit the Lunar and Planetary Institute’s educational site, with even more hands-on activities for young astrophysicists. Roam their site for educator workshops and more.

OK, seriously, I’m not the only science blogger keen on comets.

A new comet is incoming this month (May 2014).

Our guy Euler was the first one to suggest that light exerts pressure, but we had to wait over 100 years to get to Maxwell, who proved it, and then another quarter-century went by before some Russians managed to measure radiation pressure. (Also, gotta love Google Books.)

Oh, and by 1915 the proof of radiation pressure made it into Scientific American.




Chasing Comets: Notes for Project Leaders #2

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Chasing Comets

OK, we’re back for part 2.  Remember that our goal is to impart an intuitive, long-term understanding of how comet tails work.  I’ll give you an observation worksheet that students can use during the Comet Running game, but if time or attention-spans are too short for a worksheet, dispense with that element in favor of learning through movement and Socratic dialogue. (What? You think an engineer wouldn’t have read the Greek philosophers?)

If you have time and enough outdoor space for the “Game” version of this simulation, move right along to “Stage 2″ now. The promise of a chance to make their own models is what will entice the students back to the classroom. Otherwise, save the great outdoor model for another time or place and move directly to “Stage 3,” building the individual models.

Stage 2: The Game

Chasing Comets

That’s One Big Comet

This is an outdoor game, and it works to best advantage with a nice BIG comet model. Four five-yard lengths of white fabric streamers attached to a single badminton shuttlecock (“birdie”) make our Comet Chase model. A playground ball or a soccer ball (around 8” in diameter) stands for the sun.   Sort the participants into groups of no more than five and no fewer than three, and move to the great outdoors. A grassy area is safest, because this game involves some complicated running; if you’re stuck with pavement, tone down the running to “jogging” and allow a little extra time.

Start by laying out the ground rules for the game. First, each group will get to play every role. There are three parts: being the sun, being the comet, and being observers back on Earth. Remind everyone of your local rules for behavior outside. It’s harder to listen to instructions out in the sunshine and fresh air!

Take a moment to review the lesson so far. Place the model Sun on the ground, at least ten yards away. Ask an adult helper or one of the students to stand about halfway between the class and the Sun and to hold the head of the comet

Chasing Comets

Large Comet Head With Coma

while you extend the tail’s long white streamers.   This model is much more evocative of the scale of a real comet, which has a tail tremendously longer than the diameter of its coma, or head—but it’s still not a scale model. Allow for some oohs and aahs, but move on to your query: which direction should the comet’s tail point? Don’t move yet; both you and your helper just stand in place.

Chasing Comets

Large Comet: Incoming or Outbound?

Don’t be concerned if it takes more than one answer to get the right one! Some may still want to know which way your comet is moving. But in a few moments, you should achieve the consensus that the tail should point towards the class and away from the sun.

Now, add the movement and ask everyone to call out which way for you to move. Ask your helper to start walking (slowly, please!) towards the sun and then to loop around the sun. You will need to move quickly to keep the comet’s tail pointing away from the sun. In fact, even if your helper cooperates by walking slowly, you will need to break into a run! As you run, if the students aren’t already hollering directions to you, tel them to keep reminding you which way to point the tail: away from the Sun!

Pause partway and while you catch your breath you can demo a technique for helping to align the tail while in motion. With your outside hand, hold the streamers. With your inside hand, point at the Sun. The tail-runners should always find that pointing at the Sun also means pointing at the comet’s head.

Now, it is finally the students’ turn. Run as many iterations as necessary to ensure that each group does each job at least once. For instance, for a class of 20, allow time to run the game at least four times.

The Comet Group: The comet group needs one Head and up to four Tail-Runners. Name the comet after the person who’s serving as the Head. Comets are always named according to the last name of the comet’s discoverer. So if you have Robin Williams as the comet’s head, then this will be Comet Williams. Getting the comet named after him/her may compensate for the fact that the “head” only gets to walk slowly around the sun.

Meanwhile, the tail-runners get to hold the ends of the tail streamers and run to keep the comet’s head between themselves and the Sun.  In the normal course, the “tail” group will tend to lag a little and spread out, but that actually serves to more-accurately represent the shape of the dust tail. If you’re working with a two-tails group, designate one especially determined runner to represent the ion tail by taking one ribbon and maintaining a straight line from the ribbon end through the comet head to the sun.

The Sun Group: The sun group stands in the middle of your running space. One or two group members hold the model sun overhead. This makes it easier for the Comet group to see if they have successfully aligned the comet head and the sun. If the tail-runners stray out of line, members of the sun group need to to shout out “Got you! Got you!” or “Solar Wind Coming!” to warn them that the solar forces are blasting the tail.

The Astronomer Group: The people who are not part of the sun-comet demonstration still have a critical role. They are not just watching other people play the game, but they are tracking the shape of the comet’s tail as it passes around the sun, as observers on Earth. Depending on their perspective at each point in the comet’s orbit, the tail will appear longer or shorter. For example, if the comet is roughly between Earth and the Sun, the tail may look short, because it is stretched towards us. If you have time for writing, ask the Observers to sketch the comet as they see it. (See the handout.) In an average class, each student will get to observe the comet at least twice, which is very helpful for catching the unexpected views.

When every group has had a chance to play every role, take a few minutes to review one more time. As a comet is orbiting around the sun, which way does its tail point? By now, everyone should be willing to state that the tail always points away from the sun.

Still, you may still have a few hold-outs who are not quite sure this can be true. If you are lucky and it’s a sunny day, you have a hole card to play. Invite the students to each imagine that they are comets. “Guess what? You can see exactly where your tail would be. Who can point at it? Where’s your tail, Comet Human?”

If you are not saved by the insight of a student who’s totally absorbed the lesson, it is OK to resort to hints. “Everyone has one. It’s easy to see. Yes, you can see your comet tail! Where is it? Which way does a comet’s tail point? Right: away from the sun. Where’s the sun right now? What do you have that’s pointing away from the sun? It’s not bright and shiny like a comet’s tail. It’s dark, because there are no sunbeams there.

“Yes! Your shadow is your comet tail. It points away from the sun, always, no matter what direction you run.”

Stage 3: The Reward

Finally, everyone needs a model comet of their own to take home and show off and share with family members everything about how comet tails work. This is not an art project; it’s an opportunity to review and experiment individually. If some students are fussy about carefully arranging their streamers to make a colorful pattern, that is all right, but the point is to assemble a working model.

Each participant needs 24 feet of curling ribbon and a birdie (remember what I told you earlier about calling it by its proper name—be prepared for lots of giggling and teasing if you insist on that) . Cut the ribbon into eight lengths of roughly 3 feet. It is perfectly all right—and in fact more realistic—if the streamers come out various lengths. And depending on the students’ social skills, it is also all right for them to exchange colors once the cutting is done. (There are always some who prefer to discover a multi-color comet and others who prefer monotone.)

Once each student has six streamers, have them tie one end of each streamer to the head of the birdie.

Chasing Comets

Detail–Attaching Ribbon For Comet Tail

Your meticulous planners will distribute them evenly around the netting; others will be clumped randomly. Either is fine. Every comet is unique and most are quite non-uniform.

Be real. This project is not done when it the comets have been only built. Everyone needs a chance to try them out. They will, of course, want to toss them around the classroom; if this is not acceptable, make some provision for them to try out that technique outdoors. More scientific, of course, as time permits, is to allow the participants to take turns trying out their comets in the pretend “solar wind” of the classroom fan. As long as they willing and able to mind safety rules about working around a fan, by all means have everyone try out the tail position approaching, passing, and retreating from the Fan Sun. But don’t get all hot under the collar if other comets are flying through the room while you monitor the fan users. Just imagine you’re in the Oort Cloud and you’ll be OK.

Up next:  Supplies You Need and Resources You Can Use

Chasing Comets

A Cluster of Comets, Incoming & Outbound

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