We all knew that Saturn's south pole looks like a whale's eye.

It turns out Saturn's north pole is a hexagon.

Freaky.

People care so much about it. It's really less relevant than the argument over whether the millennium started on 1/1/2001 or 1/1/2000.

They followed precedent. Ceres was a planet for about two years after it was discovered (of course there was no IAB back then).

That said, James Nicoll, who is never wrong, is right about the problems with the definition. No other star but the Sun can have planets, nor (should we discover one) could we demonstrate that a new (say) Earth-sized body at 250 AU was or wasn't a planet, since we don't know whether its orbit region has been cleared... though perhaps we could prove mathematically that it must be. Perhaps the 'cleared its region' works as a mass limit.

It pisses people off -- cf. the metric system comment in Nicoll's thread -- but it was inevitable. The Kuyper Belt just has too much junk of too many different sizes; we are going through with KBOs what we went through two hundred years ago with asteroids.

But it bugs me a lot that the number of extrasolar planets has gone from 120+ to zero.

Okay, so it really is a bigger deal than I thought, because of the weird geography -- the south pole is striped with areas a hundred degrees warmer than the rest of the moon.

So maybe the Enceladeans' power plants leaked heat into the surrounding rock, which melted and produced catastrophic geysers...

Walking home after walking with Robert to school, I noticed the thin-crescent Moon (only because it happened from my vantage point to be brushing the tips of some trees as I walked, and my eyes picked up the relative movement).

Hey, cool. So I called Kate to come look.

Then I had a thought. Ducked my head inside to check my screensaver -- okay, about ten degrees north-north-east of the moon -- then went back out and peered till I found it. Fixed my eyes on it, lowered my head to be pressing ear-to-ear with Kate, and moved us till it was right at the tip of a convenient tree's top branch. She stared for a moment, then announced that she saw it, then bounced and bubbled with excitement when I told her what it was -- there are, after all, three, not two, solar system objects you can see in the sky during the day.

In fourth through sixth grade, I spent an hour each week -- and did a summer camp -- at this place. That black addition in the back of the building that you can barely see over the roof? That's a planetarium. With a Spitz starball, the same model as the one at the Discovery Museum in Sacramento.

So you might say I have been into this stuff for a while.

Well, as it turns out, the Discovery Museum has need of a planetarium volunteer for Saturdays. And they'd of course love to have someone who knows the starball and the sky doing some of their shows.

The Saturday shows aren't rocket science: you have to gear it to be comprehensible to toddlers in the audience, so you mostly keep it super-simple, point out the north star, talk about a few constellations and their shapes, and that's about it. Still -- this is an opportunity I can't pass up... the Planetarium was a significant part of what made my childhood unique, and passing this on, in small doses, to another generation is irresistable.

The shows are at 1:00 and 3:00, so I'd be there for about three hours most Saturday afternoons. I talked it over with Robert and Kate; they are going to alternate Saturdays to come with me, so that I can spend some one-on-one time with each of them. (Kate in particular is in constant danger of being cheated out of 1:1 time since there's always someone around who's either less independent or more sophisticated, so this will hopefully work out to be positive for them as well.)

I note the LA Times has some excellent commentary relating to Tycho Brahe.

Though I think "Brahean Blunder" is a bit awkward.

The point of this essay will be near the end. It is a fairly rough draft and I may update it...


Why do we do what we do? Where do you spend your resources -- your time and your money, your attention and your effort?

Food, and shelter, and health, and safety, obviously. You start with that. Some of us, unfortunately, have to end with that, or end somewhere in the middle of that. People in that situation hopefully aren't called on to contribute more than a pittance to their community, and I want to set that circumstance aside for the time being.

But set aside not all of that but only a minimal level of it. Eating at a restaurant isn't an expenditure for "food". Owning your own home isn't just "shelter." Joining a racquetball club isn't just "health". Taking self-defense courses isn't only for "safety". You're spending more than you really need on these things.

And many, most, almost all of us have some amount of money and time that's not spent on those things. Even if you just watch TV, have conversation, make love -- that's resources spent for something else. Why?

Most of us spend most of our resources on things we don't, strictly speaking, need.

I'm not denigrating it. Not at all -- quite the opposite. ( Read more... )

I'd like to see a Photoshopped picture of the new booster that NASA proposed building -- one with a big red budget target painted on the side.

Elbowing your way back into the news with the booster design for your $100-billion project to put men on Mars... right in the middle of the Congressional debate about how to afford the $500 billion for rebuilding New Orleans... smart, boys. Real smart.

This is, after all, the organization that can put men on the moon -- but we forget it was also the organization that was able to make the fact that humans were WALKING ON OTHER WORLDS dull.

And this was Zubrin's booster design and pretty obviously his Mars Direct plan. Almost precisely. Exactly the way we could get to Mars in the short term.

And because of Katrina, but mostly because of the tin ear of NASA -- my god, 'tin ear' is simply inadequate -- the chance of humans walking on Mars in my lifetime is evaporating.

What absolute morons.

"Can you give me the scientific arguments that prove that the earth orbits the sun? I teach the introduction to the History of Science courses at my U. We ask this to very intelligent college students, each year. It's harder than you think."( Read more... )

For the first time in I don't know how long I'm taking several days off from work without a specific plan to go anywhere for most of it.

That said, it's not like we're not actually going anywhere... just that we're still sleeping at home, and doing different things on different days.

I was surprised -- I listed a bunch of places we could go, and the Chabot Center was at the top of both Kate's and Robert's lists. Pleased, though, as I could hang out in planetariums all summer, had I my druthers.

So - this is what we're doing for the rest of the week.

Wednesday - Chabot Center
Thursday - Railroad Museum, then Kate's soccer practice 4-5:30
Friday - K&J to moms group, R with me to buy a bike; bookstore in the afternoon; K&R skating lesson at 5:15
Saturday - Gaea blockade almost certainly happening 12-N where N = { 1, 2, 3, 5, 6 }; if N < 3, perhaps another outing
Sunday - Nothing planned; I'm leaving it open in case (among other possibilities) Joshua decides he wants to go to the zoo

Other stuff, scheduled tentatively:
Kate wants her training wheels taken off (Thursday afternoon)
Robert, board game (Thursday during soccer practice)
Robert needs a bike (Friday morning)
Bookstore run (Friday afternoon)
Viking Hobby run (Friday, with bookstore)
Ladder purchase at Home Depot (Saturday morning)
All three kids and I need our hairs cut (Saturday morning)
Miscellaneous english, math, and science games (evenings and weekend)

Other possible stuff we might alter our schedule to accomodate:
Game with Dave and Carrie / playdate with their kids
Sacramento Aviation Museum
Discovery Museum
Sacramento Zoo

I'm glad to see the kids didn't put the Discovery Museum or the zoo as their top requests -- we've been to them the most, and kids like repetition/reinforcement, but we've done enough of both of those places that I think this week is a good opportunity to do something entirely different.

So. Tomorrow, at the Chabot Center: ( Read more... )

It seems so trivial and silly.. it's basically a "what will we tell the children?" riff: Whatever Shall We Do now that there's something bigger than Pluto in the Kuyper belt?

My little rebellion against the Tyranny of Nine was when I sent the third-graders to the playground to act out a model of the solar system, and ranked the moons of Jupiter above Pluto in interest, as is proper.

What's the point of a "planet"? I mean that seriously. We have this perfectly good word, we want it to mean something, what should it mean? What should be the point of teaching people about "planets" so that they learn all of them? What "planets" should people learn about?

I think the solar system should be organized into its groups. "Planet" and "moon" should be de-emphasized as teaching terms, focusing mostly on their historical meanings and the difficulty of counting and deciding them.

The solar system contains a sun, gas giants, worlds, and rocks. Worlds orbit the sun or orbit gas giants, and on rare occasions two worlds will orbit each other (like ours). Rocks orbit the sun or gas giants or (in the case of Mars' satellites) worlds or (in at least one case) each other.

Group the various objects in the Solar System. Teach about the groups and about the individuals in the groups. It makes things a lot more interesting than "my very educated/mature mother always just serves us nine pizza pies quickly" and focuses on the things that make each of these objects interesting, not just listing one set and giving individual, context-free facts about each but explaining how they naturally group themselves...

- The Sun
- Rocky inner terrestrial worlds (there are five; learn about them, including the two rocks -- don't call them moons -- circling Mars)
- Gas giants (there are four, unless we find one shepherding the outer edge of the KB)
- World-satellites of gas giants (there are five big ones and thirty smaller ones -- just mention the rocks in passing)
- Asteroids (focus on the big worlds like Ceres -- mention the rocks mostly in terms of dropping them into the Earth's path...)
- KBOs, comets, Centaurs, Oorts, etc.

Kids -- second-grade on -- are already taught about all of this. They just don't get the context or group, because it's all done in the wrong context -- it stars with "there are nine planets". Start with "the solar system contains the sun, gas giants, solid worlds, and a whole lot of rocks and ice... here's what each of those are."

At my pace of 21 minutes per day that I exercise (or about 4 days each week), I've finally finished watching all of From The Earth To The Moon.

Sniff.

The final episode is a heartbreaker in so many ways. Tom Hanks inserts himself in a way that warps it on many levels -- but the show itself just rends you. Where we were, how we've let it atrophy, how much it seems likely to atrophy further.

Recommended highly. Best presentation of the Apollo program I've ever heard tell of.

This is coastline.

And I'm going to be sixty years old, at least, before we get a better look.

But ... damn.

Wouldn't Carl Sagan have just given anything to be alive right now, to see this?

We all hoped for exactly this. Man oh man oh man.

The third-grade science docent project this morning was "planets and stars". Dave Groat and I did it; he told me to take the lead, because as he warned me the docent lesson itself was lame, and would need some extemporaneous work. I decided to go off-book just a tad...( Read more... )

So far this year we've had Spirit and Opportunity. Oceans on Mars, and even the president pretending he's JFK (oh, if only he was serious) and going to shoot for the Moon and Mars.

Last month we discovered Sedna, reopening discussion on the Oort cloud, Kuyper Belt, whether Pluto's a planet, and the limits of the solar system.

Last week there was a triple shadow on Jupiter, as three of its moons at once crossed the disk.

For the last two weeks you could go outside right after sunset and see all five naked-eye planets (the last time you'll be able to do this for nearly fifteen years).

Next month we launch MESSENGER, which will take about six years to get itself into a Mercury orbit.

In the next month or two you'll be hearing about (hell, you'll be *seeing*) two, count them, two, naked-eye comets -- C/2002 T7 (LINEAR) and C/2001 Q4 (NEAT) -- both of which could rival Hale-Bopp and Hyukatake.

And then there's Cassini, 85 days from orbit insertion.

Did I mention yet that this has been the best year for planetary science in, like, ever?

Took just Katie (Robert didn't want to go). The party was at the winter site, in Foresthill.
( Read more... )

Well, cool. First Oort object that isn't dropping into the solar system. And nearly Pluto's size. And apparently fluorescent red, or something.

They're calling it a "planet". That won't last. The "nine planets" meme has too much inertia; we'll never change the number.

There's no meaningful categorization that includes Pluto and Sedna in with Jupiter and Earth and Neptune, but excludes Titan and Earth's Moon and Ceres and Chiron.

The solar system contains one sun, four gas giants, about thirty to forty known worlds (solid bodies large enough that their own gravity pulls them into a sphere) and a whole lotta rocks. By that categorization, Sedna's obviously a world.

Spirit is alive, safely landed, and sending back pictures!