Walking to Pluto: Step 3

Step 3: Making the Journey

If you skipped Part 1, then you need to know know that in this activity, you will build a scale model of the Solar System as far as Pluto. You will use familiar objects and easy, approximate measurements—mostly simply pacing off distances. This is not a project about being extremely precise; the goal is to develop a strong perception of just how big the solar system is and how small the planets are within that system.

For preparation, you need only to assemble the collection of properly-sized objects listed in the requirements table (See Step 2) and print out the “cheat sheet” you’ll carry on the Walk. A glance at a map of your local area will help you decide which way to take your expedition and to identify some landmarks to stand in for more-distant things like the far edge of the Oort Cloud.  To build your own interest and enjoy some discoveries of your own, check out some of the links I’ll include in the references section (Step 4).

You can feel free to substitute alternate model planets, using the scaled sizes as a guide; however, most of the items called for can be found in an average family home, borrowed from classroom parents, or purchased at a very modest outlay. While modern kids may not find the contents of kitchen spice jars terribly fascinating, using an allspice or peppercorn seed as your “Earth” model will give them a lifelong reference point–they’ll be smelling pumpkin pie or watching a chef grind pepper and that spark of memory will remind them of this project.

Because the scaled planets range from the size of a pin point to the size of a jacks ball, it also makes sense to attach each object to something larger, such as an inverted cup or a 4 by 6 index card. If you have access to sports equipment, the bright-colored cones often used for laying out a temporary playing field are helpful. You can position the planet-holder and also tape a “Please Leave Our Experiment Here” sign to the top of the cone. And the bright colors and signs help the explorers to look back and spot the distant planets. Again, be creative! There is no need to run out and buy sports equipment—any handy rock or a brick will do to keep your objects and notes in place.

Here's my Walk kit, ready to go.

Here’s my Walk kit, ready to go.

When reviewing the Cheat Sheet, you’ll see that this model describes our solar system as far as the outer edge of the Oort Cloud. However, to go all the way to the Oort Cloud in this model is a journey of 75 miles (100 km), so don’t expect to travel that far. Instead, as part of your preparation, identify a few local landmarks 1 or 2 miles from your start point and also pick some regional and further-off destinations to match the scaled distances for such key locales as the Oort Cloud, the heliopause, the estimated positions of the Pioneer and Voyager spacecraft, the far edge of the Kuiper belt, and our further neighbors in the Universe. If you’re too short on time, the Cheat Sheet includes some general destinations, but your own localized ones will be much more meaningful to the group. If your group won’t have time to walk all the way to Pluto, find out where Pluto would be in that locale and point ahead to that location before you do turn back.

Once in the classroom, before launching your exploratory mission, start with a quick review of the concept of scale. Regardless of your target age group, toys which are also scale models of cars or airplanes or trains are helpful examples. Quickly walk through a sample of numerical proportions to give a sense of how it goes when you are creating your own scale model: for instance, sketch on the board or a sheet of poster paper a rough scale drawing of the classroom room at 1 inch per foot (5 cm per m). Rather than slowing down the project with extra work, prepare for this session by making your own rough measurements of the classroom dimensions in advance—simply pace off the length and width and note any additional features to the room. Remember, the idea is to illustrate your point, not to create an architectural drawing.

Moving on to the Solar System, start with the Sun…an 8-inch-diameter playground ball or an ordinary soccer ball fits our scale. Ask if anyone can guess what size the Earth should be to go with this “Sun”. The guesses are very likely to be way off, because most “models” used in classrooms and the pictures in the textbooks are not at all to scale. In those, Earth is shown as a recognizable ball appearing as much as a tenth the size of the Sun.

Once you have a few guesses on record, share the key data. Write on the board or a flip chart as you go, to keep the presentation lively. (Nothing kills attention like a PowerPoint!) The Sun’s diameter is about 800,000 miles (1400 thousand km), and we’re using an 8-inch (18 cm) ball, so each inch stands for 100,000 miles (or, a cm stands for 75,000 km). The Earth’s diameter is only 8,000 miles (12,700 km). So how big will the model Earth be? It turns out we need something less than 1/10th of an inch across, only 0.08 inches (0.17 cm). So now you can pass around your “Earth”…a peppercorn will work, so will an allspice seed. (And, yes, you can get away with crumbling up a bit of paper and claiming it’s a spitwad you found.) If you have a spice-jar worth of seeds, everyone can have their own Earth to keep. Let the students take a moment to actually compare the sizes of Earth and Sun. It’s a dramatic difference, nothing like what their textbooks show.

Now it’s time to figure out where the Earth and Sun should be to fit in with this scale. Start by inviting students to guess…they will likely assume you can fit the Earth-Sun model easily inside the room. So now, add the distance data they need and we can “step” through the necessary calculation:

  • The Earth is roughly 93 million miles (150 million km) from the sun.
  • In our scale model, that’s 930 inches (2000 cm)
  • or 78 feet (20 m),
  • or 39 steps of about 2 feet (40 steps of 0.5 m)


  • In our model we’re using a pace distance reasonably close to the average woman’s step length and not too far off the step length of a child who is supposed to be walking but can’t resist running. If your group is adult men or tall women, you can use the worksheet to adjust the number of steps accordingly.
  • Our scale in SI (Système international, or metric) is slightly different than in English units, so that those using the SI version can also use simple round figures.

At this point, try to keep a straight face while pretending to start building the model inside the classroom. Dramatically place the “Sun” at one end of the room and try to pace off 39 or 40 steps. Unless you’re doing this activity in a large lecture hall or a cafeteria, you will quickly run out of space (pun intended). By now, it should be clear to the students that this is to be an outdoor activity.

If the group is not too insanely anxious to get outdoors, you can take one more minute to assemble a part of the model which will fit in the room—the Earth-Moon system. Our Moon is nearly ¼ the diameter of Earth, so it’s actually an important body in its own right. And it’s close by. In our scale model, the Moon—which can be represented by a single nonpareil or cake “décor” candy—is 2 3/8” or 5 cm from Earth—so Earth & Moon can be stuck to a card or piece of paper. Keep in mind that if your group is too anxious to get outside, you can choose to save this step for your arrival at the Earth’s position in the model outside.

Earth and Moon are stuck together

Earth and Moon are stuck together

Set the very few ground rules for the mission plan. The model is built by counting steps—the students will be the ones to do the counting and you (the project leader) will expect them to try hard and in return will not be too fussy about precision or how the measurement accuracy may be affected when leadership shifts from short to tall students.   The group will remain cohesive, so no-one misses out on any important discoveries—and no one will charge ahead lest they get “lost in space”. And everyone should understand the time constraints.

When the group is large, I’ve had success assigning small subgroups to accompany one adult leader as the “vanguard” to each planet, leaving the rest behind until they have “landed,” then allowing the followers to run full-speed to catch up. If you do this, it’s important to ensure everyone has a turn to be in the vanguard at least once. If the students have been studying the planets, the vanguard students can also be asked to provide just a few key bits of information to the other explorers as features they have “discovered” about the planet they just reached. However, resist the urge to turn each stop into a seminar—the goal is to travel as far as possible across the system quickly enough to return before class time ends.

Remind the group that it’s a long walk across the solar system and then get started for real. Carry your Sun to a central location outside. If you can park Sol near a tall landmark (such as a flagpole), you’ll find it easier to point back to the “center of the Solar System” as you move further away. Take your Cheat Sheet in hand (the page from the resource kit listing your step-off distances) and read out the number of steps from the sun to Mercury. Send the Mercury explorer team ahead to place Mercury in its position, and quickly join them with the rest of the group. If the vanguard has some cool facts to share about Mercury, give them time to speak. And move on to Venus and the rest of the inner planets.

The asteroid belt portion is the first region containing many objects. If you pause at Ceres, the biggest dwarf planet in the inner Solar System, it helps reduce the stigma of Pluto being “only” a dwarf planet. The fun part in these “belt” regions is to pretend to dodge the small asteroids or other objects—while you may mention that there really isn’t any significant risk of running into an asteroid, that is no reason to turn down the chance to pretend you’re in a crowded mess of obstacles just like in the movies. Even Neil deGrasse Tyson, in his reboot of Cosmos, includes a sequence in which his Ship of the Imagination zigs and zags through, first, a crowded Asteroid Belt and later a densely-packed Oort Cloud.

If time is short or you are working with younger children, it is reasonable to make it to Jupiter (don’t forget to dodge the asteroids on the way out) point out roughly where the outer planets, Pluto, and the further objects would be found and then head back to Earth.

In any case, carry some ordinary first-aid supplies and be sure to have extra adults on hand to slow down those who want to jump to lightspeed. Don’t worry if you don’t have a straight route to use…twisting and turning your way around the streets of a neighborhood is equally impressive. If time will permit, participants can bring lunches and picnic in the Kuiper Belt before returning. And remember, as you return to collect the planet models, it is just as fun to rediscover the distances on the way back.




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Success as an author?Success as an author?

Depends what you mean by “success”

One of my writing groups (the one that isn’t a critique circle) has set a blog-post prompt of “How do you measure success as an author?”
We’re supposed to introspect, come up with wise words to inspire and console others. I don’t know about y’all, but the past two years have been a low-rising roller coaster, beginning with a brief burst of elation that my first book (my “debut” if you want to get precious about it) was coming out.

WIte, red, and blue award ribbons from a fair

Only then we had a little bit of a pandemic to deal with.

And now it’s two years later.

All That Was Asked has never had a book-launch party (it slightly predates online launch parties), a signing session, a reading at a convention—none of those things. Not uncoincidentally, it hasn’t made much dough for me or for my publisher. At least the print copies are mostly print-on-demand, so no one’s staring at a warehouse full of unsold copies and calling a shredding company.

But is selling a ton of books a success? To stay sane in this business, I think you have to measure success more on the basis of what you are doing than what you have done. If you’re making oodles of money in the publishing industry, that’s mostly a matter of luck, so is that success? I’d call it good fortune. It’s very much a lottery. I’ve read absolutely stunning work in critique circles, listened to mind-blowing readings by little-known writers, and I’ve even had people tell me after a reading “wow, that was awesome!”

What makes sense is to measure how this work—writing—impacts your life. Is this what you live for? Not in a rosy-eyed, dreamy way, not “I luv writing <3” but “writing is what drags me out of everything else” and “writing is my food, drink, and sleep” and “writing is how I exist in this universe.”

What I’m doing right now is working on projects that I’ve wanted to tackle for years—no, decades—but never could due to the vicissitudes of child-rearing, day-job workload, personal upheavals, and disability.  I’m not whining. These are just facts. I chose to raise kids, and it was satisfying work (and, yes, frustrating, too, but in all the right ways). However, doing the best job possible involved more than dropping them off at our barely-adequate schools. It meant advocating for them, fighting an uncaring administrative system, volunteering, fundraising, and, as a last-resort, homeschooling. At least in the pandemic age, there are more parents out there who understand that homeschooling—at least not ideally—isn’t a romp in the garden, it’s serious work. And, like most of us, for me that was work that had to take place in parallel with earning a living.

So right now, I’m successful. Every morning (afternoon?) I wake up, and there’s writing to do.

  • This kind of writing, which is off-the-cuff, barely edited, and hurled into the interweb’s event horizon, never to be seen by human eyes.
  • Critical writing, where I’m critiquing work by fellow writers, trying to help them make their stories the best they can be. 
  • Social-media writing—mostly Twitter—where I practice being concise, kind, and thoughtful.
  • And, finally, yes, writing my own stories, the ones I’ve been wanting to read.

What I’ve been looking for—and yes, I’ve found some, but far too few—are stories led by characters who have trouble communicating, who don’t fit in, who think differently than others but find a way through life anyhow. I’m tired of hero’s-journey stories and chosen-one tales that take themselves too seriously. I don’t mind playing with the tropes. For instance, one of my WIPs has a seeming “chosen one” in it, but the whole thing is a crock, a scheme worked up by a person who’s trying to change society and is using an old myth to get buy-in. Not that the “chosen” person isn’t worthy, but there’s no magic in the process—they’re carefully selected for capability and then trained for the job.

I’m not writing to market. I admit that. So I can’t complain about sales, not too much. It may take time for people like me to find the stories I’m writing for them. That’s OK. I waited a long time. A little longer—I can deal.

Well, I’m trying to, anyhow.

In the meantime, I’m keeping on. For me, that writers learned to use remote meetings to connect for critiques, discuss craft, conduct conventions, and more has been a compensatory gain during the pandemic. It’s not a benefit of this horrible time; it’s a thing we could should have been doing all along, and only just now learned to value. When the pandemic’s over, we’ll keep connected this way. That’s a good thing, but we don’t get to pretend it’s all right that millions of people died while those of us privileged to live were fumbling our way to this belated discovery.

I’ve leveraged that new learning, because I’m an engineer and tech things come naturally to me. I’ve let myself get roped into volunteering to help others less comfortable with the technology—and that’s OK, because participating with other writers helps me connect more deeply with my writing community.  I value the friendships I’ve formed with people I’ve only met in Zoom rooms. This is not a trivial feeling—I dedicated my Monday afternoons for half this past year to help a Zoom friend whose critique circle had lost their only zoom-capable member. That meant stepping aside from one of my other critique circles, one that needed me less. I’m returning to my prior group as of this month, because my friend’s old zoom-host has returned. I’ll miss the new friends I made in her circle, even though we only ever saw each other in little boxes on our computer screens.

Am I a failure because I had to defer my writing career? Looking back through my drawer of shelved and partly-done stories, one thing is strikingly clear—I was so young, so ignorant, so clueless. Much of what I’m writing now, I couldn’t have done when I was younger. In technique, I’m much better than my younger self; some of that gain I can attribute to years of writing science and engineering reports and papers, working collaboratively with colleagues on phrasing, structure, and word choice … plus coping with deadlines. Beyond the technique, older me is able to imagine more-complex characters, see worlds with more-different people in them. Through personal experience, I know most lives—most real stories—don’t have a “call to adventure” or a “supreme ordeal.” There’s no wise mentor waiting to guide us. We have to muddle through, try to survive in an irrational universe, and deal with the fact we’ll never quite make sense of it all.

Sure, I’m still learning. You have to keep learning. It’s the key to growth in every respect. Even there, though, I’m doing better, working actively to learn more of what I need to continue improving.

In my next posting, I’ll demonstrate my success by sharing a list of what I consider to be my 2021 accomplishments not only as a writer but also as a member of the writing community.

I’ll warn you right now: it’s a longer post.

Friday at BayCon 2013Friday at BayCon 2013

As exemplified by Thursday evening’s brief exposure to the timesense-warping effects of Triskaidekaphobicon, clearly the theory of attending BayCon is direct and clear, albeit a little boring, while the practice thereof is circuitous and exciting.  Here we will continue our study of these contrasts by once more comparing plans and realities with a half-day experience on Opening Day:

Time Frame What the Plan was What really happened
Friday afternoon Arrive early, go to opening ceremonies, then “Irreproducible Results” panel, then to a reading by Lois McMaster Bujold. Just couldn’t get out the door.  Forgot reading glasses, then key, then left door slightly ajar while trying to find my sunglasses (for driving), then became convinced (older/medical-issues) cat had sneaked out, so searched out front and called out back and looked under furniture.  Finally discovered cat hunkered down behind a chair.Arrived halfway through Irreproducible Results panel, but got a front-row seat & enjoyed panel, from nuts and bolts revelations such as that the staff of JIR are unpaid to the audience teaching JIR’s editor the song “There’s a Hole in My Bucket” and locating for him several online sources for flexible rubber with which to make graph paper.

I took a quick look at the Art Show, where they were nice enough to take care of my bag for me.  Theresa Mather‘s dragons were there.  Which one is it that I bought for Tirion?  I wondered, Should I bid on one of these dragon-butterfly prints?  I decided to come back later and sign up as a bidder.

All of the cat-oriented artwork reminded me that I was worried about my cat (not to bore anyone with a pet’s medical issues, but no-one was home to check on Manta that day), but didn’t want to miss the reading.  So stayed put for that.

Bujold read a piece she doesn’t really plan to publish at present, a work-in-progress that may or may not become part of something, but it’s a “Miles” story, so she knew it would please her fans.  The humor bits got big laughs.  And she was good about doing a little Q&A while waiting for late-comers to arrive. Turns out that one intellectual goal for “Curse of Chalion” was to work out a society in which religion had a basis in physical reality.

By then, it was after five, but decided to drive home to check on the cat –through Memorial-day weekend traffic.  The freeway was a parking lot from San Thomas Expressway to, probably, LA.  So, enjoyed elaborately costumed Fanime fans thronging streets of downtown San Jose on the unfreeway route home.  Made pretty good time, actually.  Oh, yes, and the cat was fine.  Time for a quick freezer-cleanup dinner and half an episode of “Castle” before evening sessions.

Friday evening Find out what a “boffer weapon” is and make one in the new DIY Room.  Then go upstairs and learn some Regency dancing.  Maybe get in to panel on talking to people. Boffer-making was not in the DIY room.  I had to go alllll the way to the “Ballroom” and creep past the big room where they were having the “meet the guests” reception.  Way too scary in there.   In the farthest room, kids were whapping each other with foam objects.  Aha, that’s boffing.

But no one was making weapons.Wandered about. Became “brave” and strolled nonchalantly through the reception.  Darn, there had been food.  Extroverts were  happily chatting each other up.

Wandered back to boffers room to watch the swordplay.  Maybe the “make your weapon” thing is over?  I wondered.  The program said they started at 6 and it was already nearly 8.  Suddenly, someone called out, “Who wants to make a weapon?”  Apparently, I had arrived at exactly the right time.

Two hours later, I was working on the trickiest duct-taping tasks on three swords at once, after two teen sisters frantically realized they must dash off to what they described as “Mom’s Concert” and begged for coverage while they were away.   Another hour later, and they were back in time for adding the blade tape and the final decorations.  Clever girls.

So finally 11:30 rolled around and I had myself a lovely PVC and pipe-insulation and duct-tape sword.  But not prepared to wield it yet–too exhausted.  Parked my sword in the car and wandered about a bit.  Regency dancing was already up to a lesson on the Congress of Vienna waltz, which I can’t do with my broken shoulder yet, and which they use as the final dance.

Oh, well.  Time to go home.  Big plans for tomorrow.


There are anime fans at BayCon, too.

There are anime fans at BayCon, too.

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