Teaching Plato

One more thought on David Brook's NYT column yesterday--

The most common advice conservative students get is to keep their views in the closet. Will Inboden was working on a master's degree in U.S. history at Yale when a liberal professor pulled him aside after class and said: "You're one of the best students I've got, and you could have an outstanding career. But I have to caution you: hiring committees are loath to hire political conservatives. You've got to be really quiet."
...
As a result, faculties skew overwhelmingly to the left.
...
Hundreds of conservatives with Ph.D.'s end up working in Republican administrations, in think tanks and at magazines, often with some regrets. "Teaching is this really splendid thing. It would be great to teach Plato's `Republic,' " says Gary Rosen, a Harvard Ph.D. who works at Commentary magazine.

I've got to smile at that line, not from laughing at Rosen, but in glad satisfaction. After all, I'm a conservative physics professor, and I am actually getting to teach my students Plato's Republic this term! This isn't in physics class, but in a scientific reasoning course. I'm approaching the material in my own way, treating it as a philosophy class and looking at the history of cosmology. Plato's Republic is great for this--the "Allegory of the Cave" provides an excellent discussion over how we know what we think we know. I think I should feel very happy that I get to do this.

I'd enjoy being a writer for Commentary, but he's right--teaching really is "a splendid thing."

Conservatives in academia

I'm reading David Brooks' excellent column on conservative academics in yesterday's New York Times (registration required). This subject has quickly gotten more interesting to me since I became one this Fall (became a professor, I mean). Now, I'm an astrophysicist, so politics is not part of the subject I teach, and the approaches to teaching my subject have little direct connection to political beliefs.

You won't find radical leftist astrophysicists pursuing a career in stellar remnants, for instance, while conservatives trend towards galaxy evolution. But Brooks says there are such distinctions among historians and other professors of the humanities. Not always overt political discrimination, but a preference for particular research subjects that are more radical or have an appeal to liberals.

I'm not finding this to be the case where I am, thankfully. There are plenty of conservatives (or apparent conservatives) among the faculty here, even outside the physical sciences. Things were a bit different when I was at the Space Telescope Science Institute as a grad student, or at NASA as a postdoc, where there was a noticeable liberal tilt among my coworkers. The odd thing is that the liberals tended to feel no compunction about bringing up politics in unrelated conversations, and they would usually phrase this in a tone that assumed everybody else would agree with their opinions (about Bush, Iraq, etc.).

The conservatives, on the other hand, were much more circumspect about having political conversations. One friend of mine, in fact, would only get into any frank discussions with me after he'd closed the door to his office! Interesting thing is, we had ways of quietly figuring out who the other conservatives were and would exchange guesses about whom else we could safely bring into these conversations. It all seemed so exciting and conspiratorial.

Saddam Fooled Himself?

Time magazine has an interesting article online that raises the possibility that Hussein's WMD programs had not been rebuilt after the Persian Gulf War, but that he wasn't aware that he didn't have these weapons. Essentially, that he was fooled by his own subordinates. (Link via Drudge.)

This idea was out there some months ago as speculation, but I can't remember where I read it. Probably National Review. Time's article strikes a somewhat anti-Bush tone, but at least the facts of their report are new and interesting. Be warned that this article is very poor in style, being riddled with typos, mostly mistakes in capitalization. I'm assuming that it was submitted in haste and will be corrected soon.

China next in space?

John J. Miller has some discussion of the motivations behind the Chinese manned space flight program today on National Review's "Corner." I won't get into this just now (no class today, so I'm trying to get some research done), but I want to comment on the Chinese program soon. Keep in mind that they claim they're not aiming merely for a quick trip around the earth but intend to be on the moon before long!

E, glad to hear your family's OK! I saw how much damage there was around them when I was there last weekend. Hope they didn't lose too much food when the power went out. The lack of dry ice was a problem there--one of the two local CO2 factories lost power themselves, ironically.

Against "universal jurisdiction"

Dr. Henry Kissinger has an excellent discussion of and argument against the concept of "universal jurisdiction," such as is claimed by the International Criminal Court, in this article in Derechos Human Rights from 2001.

I'm also against the concept, for many of the reasons Dr. Kissinger outlines. The idea creates problems similar to those of ex post facto laws. Furthermore, it violates the sovereignty of countries and therefore the sovereignty of the people in those countries--their right to govern themselves--even under free, democratic governments.

Orbital Space Plane

Contributor Jeff e-mails me the following thoughts on the continuing ideas of an "Orbital Space Plane"...

At

http://www.spaceref.com/news/viewnews.html?id=870

SpaceRef.com has an editorial from a former astronaut bemoaning the
possibility that the Orbital Space Plane might be a vehicle fine-tuned for
the task of safely and reliably getting astronauts to and from the Space
Station. Don Peterson writes that lack of capabilities such as the
ability to loft large cargos, robot arms, etc. will render the OSP a dud.
Further, because the intent is to produce a vehicle quickly, the OSP
would rely almost entirely on existing technologies, and so it would not
produce technological advances.

Those criticisms have some merit, and would have even more if the goal of
the OSP were indeed to produce new technologies or a vehicle with a wide
range of capabilities. But if we give yet another try at developing a
manned vehicle made of pure "unobtanium," would that be better? Over $3
billion dollars have been wasted in shuttle follow-on projects (NASP,
X-33, X-34, X-38). Should we cross *both* sets of fingers this time,
hoping the new-new-new-new-new shuttle successor doesn't get cancelled for
having been too ambitious?


Do we even NEED another shuttle-like vehicle, capable of lofting large
cargos, serving as a mini-space-station, and returning large objects from
orbit? As the Columbia Board Chairman said it, don't develop a vehicle
and then try and figure out what you can do with it. That happened with
both the shuttle and station, and we'll be paying off those projects for
another 15 years.


But Mr. Peterson's case could be restated: the OSP is an interim solution
for a significant problem, yet it may not offer easy evolutionary paths to
address the needs 15 years down the road. Instead of criticizing the OSP,
one might suggest that in addition to the OSP, we need a parallel
development track for either extended capabilities for the OSP (via a
mini-space-station or orbital maneuvering vehicle) or an entirely
different vehicle...with one big caveat. A clear mission needs to be
defined for the second-track capability.

The OSP is indeed a limited vehicle, as currently conceived, but we do
need it as soon as possible to send crews and light cargos to and
from the Station. Expecting continued service from the shuttle for the
next 15 years strikes me as dangerously optimistic.

What isn't clear is what we need for the post-Station era, because the
goals of American human space flight in the post-Station era have yet to
be defined.

-J

Volunteer Tailgate Party

Yours truly represented Hypotheses Non Fingo at last week's Volunteer Tailgate Party, the biweekly, super-secret get-together of Tennessee bloggers. Check out Up For Anything for a report of the good ol' time had by all!

Post-Isabel stories

Well, I'm back from a Federal disaster area and had to get back to teaching Monday with less than four hours of sleep. I've got some good stories from the D.C./Md./No. Va. trip--Isabel damage, flooding, Phi Beta Kappa discussion panels, and hanging out backstage with Will Hoge and his band!

I just finished up a tedious but satisfying bit of data collection for my quasar research, and it's time to cook something for supper. I'll post more later. And if I can figure out how these free online image hosts work, I'll see about posting some photos of an air show of WWII fighters, including "Glacier Girl," the P-38 they dug out of the Greenland ice cap.

Science and Religion

Rob just e-mailed me with this article on science and religion. Anthony Rizzi, the head of Princeton's Institute for Advanced Studies (that name always strikes me as very vague...but maybe that's the point) is working on restoring the relationship between the two. He has a new book out, called The Science Before Science: A Guide to Thinking in the 21st Century. The article is a good interview with Rizzi. More on this topic later--I'm about to make that trip to D.C. Looks like most of Isabel has left my path, at least.

CORRECTION (9/23):
Alert reader Dave Gill just pointed out to me that Rizzi is not with Princeton's IAS but with the Institute for Advanced Physics, which is in Baton Rouge. Actually, that might impress me more with the direction he's apparently taking them, since I imagine that, guessing from its name, the IAP has been somewhat more narrowly focussed than the IAS. I'll have to read more about this.

'Twas Ever Thus

"...and as for the essence of the question, or its moral side, so to speak, he doesn't touch on that at all, he even rejects morality outright, and holds to the newest principle of universal destruction for the sake of good final goals. He's already demanding more than a hundred million heads for the sake of common sense in Europe, much more than was demanded at the last peace congress. ..."

--The Demons, Fyodor Dostoevsky
(p. 94 of the 2000 Everyman's Library edition)

The Demons was written in 1871-2, and it is strange to read it today, because the attitudes of the radicals it depicts seem so modern, so like what we'd been accustomed to throughout the 20th century. But "human nature has no history," and in our lifetimes, we've only seen the fruits of the ideas the radicals began to develop well over a century ago.

Columbia accident: lessons not learned from Challenger

Our contributor Jeff e-mails with the following observations on the two Space Shuttle accidents:

There was a good article by CBS News on Spaceflight Now this morning:

www.spaceflightnow.com/shuttle/sts114/030917mmt/
about a press briefing by Wayne Hale, who replaced Linda Ham as the leader of the shuttle Mission Management Team. One part was especially striking.


A little introduction: Dr. Diane Vaughan wrote "The Challenger Launch Decision," the definitive account of the sociology of the events surrounding the Challenger disaster. It was nominated for the Pulitzer Prize and National Book Award, among other honors. It is an excellent book, easily understood by non-technical people. Dr. Vaughan made a strong case that defective organizational structure and communications channels at NASA played a leading role in the Challenger loss. The parallels with Columbia are striking.


This is a statement made yesterday by the current chair of the shuttle Mission Management Team, Wayne Hale (quoted by CBS News):

"I didn't know who Dr. Vaughn was when she appeared at the CAIB hearing," Hale said. "I came away a little unimpressed with it but I said I ought to go get her book and look at what she's got to say. I sat down and read ("The Challenger Launch Decision") and when I got done with it, I said wow, there is a lot of good stuff here that I never thought about. And there is valuable place for us to learn some things."

My reactions are twofold. First, how someone with Mr. Hale's experience and position within the shuttle program could not have run across Dr. Vaughan's book mystefies me. It underscores the Columbia Accident Investigation Board's finding that NASA is not an effective "learning organization;" that is, it is not learning from its past mistakes.

In the Navy, as the CAIB noted, submarine crews study in great detail the Thresher and Scorpion losses, so that they will not be repeated. But at NASA, as the CBS story notes, "many at JSC (NASA's Johnson Space Center) resented the appearance of sociologist Diane Vaughn, an expert on the decision to launch the shuttle Challenger, at a Columbia Accident Investigation Board Hearing."

But second, and on a hopeful note, Mr. Hale seems willing to learn and change the procedures. He is talking the talk, and hopefully will be able to follow through. The CBS article notes that Dr. Vaughan "now is among the experts being sought by NASA." Perhaps positive things are indeed happening.

Perfect timing; Military and the Press panel

I've got a panel discussion in D.C. I'm moderating Saturday, so I'm driving back to the District from out here in the Midwest tomorrow. I was planning to make the trip...oh, say...now, but friends back there have warned me off, saying that Western Maryland is supposed to get 12" of rain tonight, and I'd be going through that sometime around midnight. So I'll drive through the storm Friday during the day, which will at least be somewhat better, and it should have further diminished by then.

This panel discussion will be fun. Our topic is the new relationship between the military and the press, especially in Iraq, with the embedding program. The Washington, D.C. Phi Beta Kappa Association (in which I'm an officer) is cohosting this with the American University chapter. It will take place at AU's Kay Chapel, Saturday at 2:00 PM. We're hoping to get C-SPAN to cover this, but we won't know until Friday afternoon.

Orbital Space Plane and the Columbia accident report

Our occasional contributor Jeff just sent his comments on a good article about the Orbital Space Plane and the results of the Columbia Accident Investigation Board:

There's a new article on the Orbital Space Plane at

http://www.spacedaily.com/news/rocketscience-03zy.html

Pulling no punches, Jeff Bell discusses the capsule vs. winged space plane
argument again, and notes:

"(T)he London-based magazine The Engineer reports that both Boeing and
Lockheed-Martin have abandoned their winged designs and will propose
Apollo-derived semi-ballistic capsules for the OSP competition."


As I've noted before, the CAIB report was (deftly) pushing that way
already.

In the final analysis, a capsule is probably simply better for the OSP
mission. A capsule production line offers the great benefit of keeping
the technology current via upgrades (either as the military does with
block upgrades, or through simple evolutionary changes). Additionally, we
won't be in the precarious position of depending on a small number of
vehicles for two decades. If NASA had pursued a small "buy" of winged
OSPs, 4-6 vehicles, then the loss of one or two might have crippled the
whole program. Losses should be considered inevitable, even as we strive
constantly to avoid them. And I suspect that in the end a capsule will
just be easier to design, build, and operate, and likely a whole lot more
flexible, than something with wings.

A quick look shows that an entire Apollo Command & Service Module (CSM)
had a mass of about 30,000 kg, of which 18,000 kg was propellant. The
heavy-lift version of the Atlas 5 can put about 20,000 kg into low Earth
orbit, and the Delta IV heavy-lift version about 26,000 kg. An OSP won't
need anything like 18,000 kg of propellant, so it ought to be possible to
launch a capsule and some sort of service/cargo module at the same time
to take care of at least some of the space station resupply burden. One
can easily imagine some kind of evolutionary development that would
exchange the capsule for a second cargo module, for even greater cargo
capacity.

Of course, with the boosters costing $100 million or more, launches won't
be cheap. However, we might move closer to the routine access to space
that the shuttle promised, but which it proved unable to deliver.

-J

Weird new trends in church services

I went to my first church service in this town yesterday. Nice congregation, very friendly, apparently conservative in a religious (and probably political) sense. Just one wee little problem. An annoyance, really, but a pretty big annoyance at that. Up above the pulpit, next to the organ pipes, they've installed a projector screen, where they ran a Powerpoint presentation throughout the service!

When the service started, they projected up the names of those with prayer concerns, like you'd normally find in the bulletin. Actually, I forgot to get a bulletin, so I don't know if this was an overlap or not. Then during the hymns, they'd project the lyrics. And--get this--during the sermon, they would project pictures to illustrate the pastor's major points and then have key words move into place.

It was really distracting!

Nice bunch of people, but I'm going to try out a different church next time (30 yds. from my place) and see what I think of that one. Maybe I'll stick with this one, but we'll see.

Reminds me of the one (and thankfully only) time my church at home tried anything similar. Christmas Eve service ~4 years ago, they set up a slide projector in the balcony, with a screen above and behind the choir. During the reading of the birth of Christ, they'd project slides of actors protraying that part of the scene. This was bad enough. Gaudy, cheap-seeming... But then the real fun started. You could hear the "kachunk" sound of the slides advancing, and after the first few slides were shown, there was a rapid "kachunkkachunkkachunkkachunk!" as the forward button got stuck and ran through the slides like it was trying to imitate a movie projector. The operators started wrestling with the projector, so the images were moving wildly, all across the front side of the sanctuary, and there was what sounded like muffled cursing coming from up in the balcony until one of them finally just pulled the plug.

Unfazed, the readers continued with the story, with breaks for the appropriate anthems and hymns. By the next portion of the reading, the operators had managed to fix the projector, so they turned it on again and had to flip rapidly through several slides, until they'd caught up with the appropriate section of the reading. And sure enough, after the third or fourth slide, the "forward" button got stuck again, and there was more muffled cursing (actually it was probably just heated discussion between the operators on what to do), and the images were flashing up behind the choir in rapid succession, then shaking and swerving left and right across the wall before once again having the plug pulled.

That was the last time they tried that.

Private Spaceflight

A reader sent us an e-mail a while back, following E's posts on spaceflight. I've gone back to the e-mail and taken a look at the links to Scaled Composites and XCOR Aerospace, which are impressive. I followed the private spaceflight projects a lot during the late 1990s, but I'd forgotten about it lately. Burt Rutan's Scaled Composites is working on suborbital flight now and already has done some atmospheric flights. The interior of the cockpit is amazing-looking. XCOR has some designs that look like earlier proposals for the Space Shuttle, but also aiming at suborbital flights.

I'm going to have to keep checking on them. It will really be something when we have the world's first private manned spaceflight. And won't it be something if a private American company beats the Chinese!

Speaking of Chinese spaceflight, The Weekly Standard's Erin Montgomery reminds us that the Chinese are aiming for the Moon. Hmmm... More on this later.

Disgusting NPR comments

NPR's Andrei Codrescu is commenting on two "evil geniuses" who died this week: Edward Teller and Leni Riefenstahl. His commentary is not as morally relativisitic as his introductory sentences suggested, and he acknowledges that in terms of their intents, there's no comparison--Teller worked on the hydrogen bomb as something to oppose murderous Communist dictators, while Riefenstahl was glorifying Hitler. But then he concludes by suggesting that the two of them are "together in the next world," suggesting they're both in hell.

I'm really annoyed by this, because his conclusion is an example of moral relativism, and he mistakenly thinks that one's going to heaven or hell doesn't come from what is in the heart but rather the potential consequences of one's actions. The fact that Teller's H-bomb wasn't ever used in battle and never killed anyone seems to have slipped by him, as does the fact that its deterrent value probably saved many lives. There are lots of things we do that could have bad, unintended consequences but...don't.

Furthermore, if potential, unintended consequences are Codrescu's standard of ultimate Judgement, then does he likewise picture Albert Einstein and Robert Oppenheimer as squirming in flames and sulphur lakes? After all, they respectively proposed and directed the work on the original atomic bomb. Is Teller worse because his version is more powerful? Does he picture Benjamin Franklin and Thomas Edison roasting on a spit in a Hieronymus Bosch painting? (Or see here.) After all, the unintended and bad consequences of electricity are too numerous to mention.

I found Edward Teller's homepage at Stanford's Hoover Institution here. I think the biography they wrote is as good an obituary to him as I've read.

NASA response to the Columbia Accident Investigation Board

Let me just post this NASA e-mail without comment for now. Not all that much information in itself, but it provides some links to NASA materials on this subject. I've redacted some e-mails and point-of-contact names.

Subject: Special Notice - NASA Response to the CAIB Report

This "Special Notice" is from NASA Headquarters.
Point of Contact: [---].
----------------------------------


NASA Response to the Columbia Accident Investigation Board (CAIB)
Report

The Columbia Accident Investigation Board has provided NASA with
a very helpful roadmap for returning to safe flight activities.
As Administrator O'Keefe has pledged, we will not only implement
the CAIB's recommendations to the best of our ability, but we
will also seek ways to set the bar even higher as we emerge from
the Columbia accident as a safer, stronger and smarter Agency.

To do this, the "NASA Implementation Plan for Return to Flight
and Beyond" outlines the path that NASA will take in implementing
and building upon the CAIB's recommendations. The plan will also
address the activities necessary to sustain safe flight
operations for as long as the Space Shuttle's unique capabilities
are needed in the future. Both the CAIB report and the
Implementation Plan can be found on the NASA web site at:
http://www.nasa.gov. Our Plan is not some kind of sacred text
whose words are set in stone. It is a 'living document' that
will be continually updated to reflect your good ideas for how we
may best accomplish our return to flight goals, as well as to
record our tangible progress toward safe return to flight.

In the spirit of One NASA we encourage all NASA employees to read
both reports and provide us with your specific feedback. We
really want to hear from you about how we can best get the job
done and we will carefully consider all your comments. They can
be submitted in a number of ways. First, you can send them to a
new email address: [---]. Second, as
Co-Chairs of the Space Flight Leadership Council, we would be
pleased to review any comments you may wish to send to us
directly at: [---],
[---], and
[---]. Finally, you can make your
suggestions to any member of the NASA management team, as we will
all be working together throughout the daily Return to Flight
planning process.

With your help and support, we will embark on this new chapter in
NASA's history with a renewed commitment to excellence in all
aspects of our work, a strengthened safety ethos throughout our
culture and an enhancement of our technical capabilities.

Babylonian mythology and Isaac Newton

The second day of each class was a real improvement over the first. I always make a jumbled-together introductory lesson when starting a course but get into a comfortable swing of it later. Yesterday was the second class of Scientific Reasoning, and I was still on ancient mythological cosmologies. I had them read the Babylonian Enuma Elish, their combined creation and dragon-slaying myths. I hoped they would enjoy it, but if you're not familiar with who the gods are and what they represent, it can be slow going and confusing. I was prepared for 30 bumps-on-logs yesterday morning, but instead I had them immediately asking questions, even before I'd started my lecture (I'd planned to summarize the story and meaning, in case they couldn't make much of it). We wound up having a lively class discussion for nearly two hours, and I had to cut them off eventually so I'd have time to give the summary, just in case.

I had almost forgotten about this, but at the end I brought up Tablet V, ll. 62-68:

Thus he [Marduk] covered the heavens and established the earth.
. . . in the midst of Tiamat he made flow,
. . . his net he completely let out,
So he created heaven and earth . . . ,
. . . their bounds . . . established.
When he had designed his rules and fashioned his ordinances,
He founded the shrines and handed them over to Ea.

Notice how after creating the physical universe, the god Marduk sets his rules and ordinances. This strikes me as meaning natural laws. And the concept of natural laws would probably be a prerequisite for doing serious science. The Egyptians, whose creation myths we studied earlier, seemed to have had a confused and incoherent cosmology, not nearly as systematic as that the Babylonians laid out. Similarly, the Egyptians seem to have been less advanced star-watchers than the Babylonians, who managed to understand the eclipse cycles and were able to predict some planetary motions. An idea that the universe is "not capricious" and operates according to laws that can be discovered and understood is a necessary part of modern science, but I think the Babylonians had some inkling of this long ago.

I mentioned my interpretation of this line to the class, and I was very impressed when a student piped up that that was what Isaac Newton had argued. That's exactly a point I was planning to make several weeks from now when we will study Newton, but the students have brought it up already!

sniff! I'm so proud of them!

Then late last night, I had my astronomy lab take out our 4" Celestron telescopes and look at Mars and the Moon. They seemed to have a ball; one girl brought her dad along, and a history professor who is an amateur astronomer met us with his much larger telescope. The students got a thrill out of seeing the south polar ice cap on Mars and even made out distinct land features. The two dozen donuts I brought along probably helped their enthusiasm.

Back from break

Sorry for the week-long absence from posting. I just began my first professorship today and am still in the process of moving in, unpacking, putting together class notes, and figuring out how to use the office phone mail.

Some changes in going from NASA to academia: first and foremost, the university's computer service insists on me having a Windows-based machine, while I've been accustomed to my (old but serviceable) Sun running UNIX. The only thing I know I'll want to use on this will be our calendar program to schedule planetarium shows. Fortunately, the engineering department, where my office is physically located (the other physics professors are in a neighboring building), has gotten fed up with the bureaucracy and slow service of the university computer services. So they seceeded and set up their own, independent linux network.

Hallelujah! So right off the bat, I've got people around me who administer a UNIX set-up, and they've even got wireless ethernet. So my next job is to get my Mac OS X laptop rigged up with a wireless card, and I'll even go for setting up my own home wireless network, which will be a big help.

Classes have started off OK. I didn't choke today, although I wasn't perfectly organized. I'm teaching a philosophy class (today) in addition to astronomy (tomorrow), and I was going over Egyptian mythology and cosmology this morning. I'll excuse today's less-smooth teaching with the notion that Egyptian mythology wasn't perfectly organized, itself. In fact, having grown up reading so much of Classical Greek & Roman mythology, I was surprised at how jumbled the Egyptians were. Seems like competing cult centers kept revising the relevant myths to have their gods come out on top.

Their overall cosmology was somewhat mixed up, too. One myth has the starry sky being the Celestial Cow (really), with stars on her belly, four legs for the four cardinal directions, and the sun somehow sailing across her back(?). Then another myth has the sky be the body of the goddess Nut, separated from that of her brother Keb (god of the earth) during daylight.

But the Celestial Cow, as I'm calling her, was good for a laugh from the students. There's something inherently funny about cattle. I don't know quite what it is, and I raised them when I was growing up. Perhaps it is, as the great [A-hem! --ed.] poet William McGonagall put it, that

A chicken is a noble beast,
The cow is much forlorner;
Standing in the pouring rain,
With a leg at every corner.

Ahhh...I've managed to put Egyptian cosmology together with McGonagallian poetry. What's next from this fertile mind? \end{sarcasm}

Yikes!

Geez, E--that sounds outrageous! I totally agree with you, if those are the facts of the case. The state has no business interfering in this. Of course, I need to read the article first...

UPDATE
OK, after reading it, I'm even more disgusted, because the article really does say "kidnapping"! I get the impression the state is trying to take formal custody of the son to force the original doctors' recommendations.

This is an abuse of power. I remember a case back in the mid-'80s of a girl with a large tumor. Her family were Christian Scientist, I think, and didn't believe in various kinds of medical treatments. There was a big court case about it, and I don't remember the outcome. But my opinion has been that, although I would want the parents to do the best for the child, even making an unwise medical decision is not sufficient grounds for the state to involve itself. I think there should be very little in which the state should overrule the autonomy of a family.

That said, this family doesn't even go that far. They're not avoiding all treatment but are hoping for one less troublesome that chemotherapy. I doubt they'll find one, but it's their right to do so.

More on spy satellites

Jay Manifold sent me a great post from last year on new spy satellite technology using interferometry. Compare this quality to the much cruder Hubble-style approach below!

Hubble as Spy Satellite: Solution

OK, class, everybody get out your homework...

Last week, I posted a question about using the HST ("Hubble Space Telescope") as a spy satellite. It's very easy to figure out how small an object on the ground can be resolved under "ideal" conditions, and in fact, I think I'll assign my astronomy students to do this for homework (assuming they don't read this blog).

Let's review the three basic pieces of information we need:
1) HST's primary mirror is 2.3 m in diameter.
2) We're observing in blue light, with a wavelength of 430 nm.
3) HST is orbiting at about 320 nautical miles above the earth.

(Incidentally, the altitude changes, as the atmosphere drags HST down slowly, and then the shuttle has to carry it back up higher every 3 years. But 320 n.mi. sticks in my head as typical.)

The formula you need to know is the "Rayleigh Criterion." This is a common (basic optics) formula for how far apart in angle two points have to be in order for a telescope to resolve them as separate objects. Therefore, the Rayleigh Criterion also tells us how small an object can be resolved: the "two points" are the opposite ends of the object.

The Rayleigh Criterion says that the points must be separated by at least an angle theta:

theta (in radians) = 1.22 lambda/diameter

where lambda is the wavelength of light, and diameter is the diameter of the telescope's main mirror or lens.

We get 2.28x10^-7 radians as the smallest angle. Then using our geometry and the small angle approximation, we find that from an altitude of 320 n.mi. (=590 km), we can resolve an object as small as 0.135 m, which is just 5 1/4 inches!

Ok, so you're not reading license plates off of cars, but that's not bad.

CAVEAT
Now, I said this is under "ideal" conditions, which in this case means no atmospheric effects. Atmospheric seeing limits the resolution of ground-based telescopes to about 1 arc-second under good conditions (4.8x10^-6 radians), about an order of magnitude wider angle than we used in this problem. But! All hope is not lost. Remember that ground telescopes are physically next to the atmosphere, while the HST is far above it.

Imagine standing in the shower, with a translucent curtain. You can see out, but everything on the other side of the room is blurry. But if you're standing on the other side of the room, you can actually see objects right behind the curtain in fairly sharp focus.

This is because the blurring only affects that part of your line of sight that moves through the air (or shower curtain, or whatever).

A very, very rough estimate tells me that if it's the bottom 50 miles of air that do the blurring (I actually have no idea; this is a guess), then atmospheric seeing might limit us to objects no smaller than 1 1/2 feet. Still not bad, and I think the way I did it is a pessimistic and crude assumption.

Could anybody out there improve on the shower-curtain seeing part of this? E-mail me.