Monthly Archives: August 2006

Watch a Spacecraft Crash Into the Moon, LIVE!

Quick! Get a telescope!

The ESA’s SMART-1 spacecraft has run out of fuel after a successful 2 year mission to test new spacecraft technology and study the moon. It is now scheduled to make its own tiny crater on the evening of this coming Saturday September second as it slams into the Lunar surface at a speed of 7,200 kilometers-per-hour. The resultant flash is only likely to last for 20 milliseconds or so, but it may very well be visible, particularly if the dust plume rises high enough to pass outside of the Moon’s shadow into direct sunlight.

The nominal impact is predicted to occur at 5:41:44 UT (Universal Time) which is the same as 10:41 pm PDT. There is always the possibility that the space vehicle will auger in on either the prior (during daylight, and so invisible) or successive orbits (visible very early the next morning).

https://i1.wp.com/esamultimedia.esa.int/images/smart_1/Lune02bis_hi.JPG
The tiny red circle depicts the predicted point of impact.

All sorts of interesting science surrounds the mission, but the parts that interest me the most are the technologies used to get the spacecraft to the moon. I am always awed by the incredible precision of our understanding of gravitational trajectories. Check out the planned orbital path that begins with a spiral around Earth with an increasing radius up until it hits a critical stability point and is suddenly transferred to an orbit around the Moon.

https://i2.wp.com/esamultimedia.esa.int/images/smart_1/img16a_copy.gif

One other particularly interesting aspect of the mission is that SMART-1’s primary propulsion system hearkens to Star Wars (the movie) technology. Remember the Galactic Empire’s grey and black T.I.E fighters? Well, T.I.E stands for Twin Ion Engine. SMART-1 traveled the full distance and maneuvered for two years on a Xenon Ion Engine rather than a traditional rocket thruster.

https://i1.wp.com/esamultimedia.esa.int/images/Science/smart1_101.jpg

Here is a close-up CAD rendering of the business end of the ion engine. In contrast to a traditional rocket which directs a chemical explosion out of a nozzle to generate thrust, the ion engine strips electrons from Xenon gas, and then uses an electrostatic gun (a high-tech cousin to the one in your tube TV) to accelerate the ions out the back of the craft. While the volume of ionized gas is much smaller than what a chemical rocket would expel, the velocity of the ejected matter is over ten times greater, and there is much less wasted heat and energy. So while the thrust per second is lower, the total thrust can be many times greater for the long-burning ion engine.

(Images courtesy of the ESA.)

2 Comments

Filed under Astronomy, Technology

Help Fight Math Anxiety

I was browsing an interesting post on Jennifer’s Cocktail Party Physics blog the other day when I stumbled on a mini flame-war about a topic dear to my heart. The original post was about a call from www.feministpress.org for book proposals to help inspire women in science.

The flamers were arguing about whether something that is hard and potentially frustrating can be fun in the context science education, and whether it was the off-putting general difficulty of science that was the problem. I couldn’t resist, so I donned my asbestos boxers and joined the fray.

Ultimately, I felt the argument was about whether people can be taught to find satisfaction in accomplishing something difficult. Here is my post, reproduced here:

One of the biggest barriers I have had to surmount across my years in academia as both science student and teacher is frustration. One of the biggest and most important frustrations has been that of failing to immediately comprehend something.

Different people respond differently to frustration. Some give up and try something else that is perhaps a little less challenging. Others, who are more comfortable remaining in that frustrating state of not-quite-understanding might persist and continue to work on their problem at hand. I am completely convinced that “Math Anxiety” is simply an inability to withstand the frustration of NOT KNOWING something long enough to actually learn it. (Note that this can be either willful or subconscious, but I have had great success in surmounting this particular claim.).

For some, the prospect of that anticipated spark of inspiration or delight that comes from persevering to the point of enlightenment drives them through the uncomfortable uncertainty period. Over time, students learn to be more comfortable and less bothered by NOT KNOWING, and can progress through harder and longer problems as their tolerance and comfort increase. Ultimately, people can learn to anticipate the challenge and revel in the idea that if they can just concentrate long enough, they are sure to eventually learn something and eventually delight in the whole process start-to-finish.

I happen to believe this is NOT an innate ability. It is a learned skill. If there is no properly self-aware teacher available to guide and settle the student through the early frustrations, and the educational environment fails to foster the mental discipline or world-view of intellectual reward through calm persistence, we end up with people who equate “hard” with suffering, who give up on ever achieving profound and potentially life-changing realizations, and who will never know the real joy of figuring out complex and interesting things.

Our schools need more teachers who understand this sort of thing.

So help fight math anxiety. Help people relax and enjoy not knowing. Help people accomplish ever-more-difficult goals.

Anyone else out there have a good story about overcoming math anxiety?

2 Comments

Filed under Education, Math

Science Under Attack: The Big Bang

I have a theory.

Well okay, it’s not really a theory in the scientific sense of the word. I certainly haven’t met that standard of having assembled an overwhelming body of physical data and supporting experimental results to the point that there is no reasonable doubt of its validity.

I’m talking about a theory in the simple every-day layman’s sense of the word. As in, “I have a theory as to why the water isn’t draining from my toilet; it must be due to that large plastic dinosaur my four-year-old was teaching to swim yesterday.”

My theory is that somehow, the Republican Party has run into a serious problem that they fail to even recognize. Their decision to seize political control of a broad range of agencies who depend on informed scientific and technical support has required that they replace many people who have the actual technical knowledge to perform their duties, but are unfortunately encumbered by “subversive” political views with appointees who can toe the party line, but just don’t have the knowledge, training, or experience necessary to make incredibly important decisions.

The problem’s that have arisen from this unfortunate position are now too numerous to list in a simple blog post while still preserving time for my day job. They range from politically motivated funding decisions which are effectively shutting down critical programs (EPA and Global Warming, NSF and Stem Cells, NASA and its entire Earth Environment mission complement) to redirection of funding from FEMA programs intended to protecting the country from extreme natural disasters towards provably less likely and less damaging terrorism defense to the direct detriment of everyone near the Louisiana and Mississippi coast line. Talk about an example of worrying about the wrong thing. Just look at the statistics on deaths, damages, insurance claims, and refugees; there is simply no comparison of scale, yet the misdirected flow of dollars persists.

Other more alarming direct evidence in Iraq is similarly ignored. Recall the retired Generals who called for more troops, and the administrations longstanding insistence that no further troop deployments were necessary? I would say the recent diminution in Bagdad violence by more than half within one week of bolstered deployments puts the lie to the administration’s original strategy. Imagine if we could have had the additional strength there from the beginning. Again, the politics had won over the physical evidence until there was just no possible way to further deny reality. But things had to get pretty damn bad before the undeniable realization set in. What do we do when our country’s technological and economic future begins to follow a similar path? I believe we have already set foot on that road to disaster and desperately need to find another way.

Fortunately, I believe that while much of the damage will take some time and concerted effort to rectify, these poor choices can be remedied rather directly when a new administration comes into office. But I believe there is some longer lasting damage that may result from a change in “the political game” that this administration pioneered. More so than any other administration in history, the Bush administration placed decided in favor of politically, morally, and religiously motivated policies and against what that national science community had determined were the prevalent theories of how the world was actually changing. They have repeatedly chosen to make decisions based on their faith in how the world should be, rather than how physical evidence and theories showed the world to most likely be. But worse than the immediate damage of this short-sighted job and money shuffling, they have set a precedent that it is okay to place religiously or politically oriented directors to “manage” what and how science and technology is published and presented, or even accessible to decision makers and the public. This places the entire technological foundation which elevated the US above Europe, Asia, and the Middle East at risk, not just from this administration, but other later administrations as well that follow suit and employ similar tactics to forward their respective political agendas.

Part of my theory rest on the fact that I don’t think most politicians, political appointees (or perhaps the general public) even understand the definition of the word “theory” in the scientific sense, and therefore misapply the layman’s usage. When a scientist tries to explain the theory of evolution to a proponent of creationism or Intelligent Design (someone who typically has little or no scientific or technical education whatsoever) the listener mistakenly hears the softer “theory” and can be easily mislead to a belief that there is some controversy or doubt, when there really is no doubt whatsoever.

A rather amusing/disturbing event which highlighted this very issue showed that even the scientifically inclined could fall into the trap of misused “theory” definitions. Most of you are probably aware of the incident in which the NASA climatologist James Hansen’s research in global warming and greenhouse gas emissions was censored by the Presidential Appointee. The New York Times article that broke the story created a mild sensation and ultimately resulted in a retraction and new censorship policy announcements. Until last weekend, I had read many of the ancillary news reports, but never the originating article itself.

When I finally picked it up and read behind the fold, I came across this gem from the very same 24 year-old former Bush campaign intern that tried to censor Hansen: (Note my added emphasis did not exist in the original.)

In October, for example, George Deutsch, a presidential appointee in NASA headquarters, told a Web designer working for the agency to add the word “theory” after every mention of the Big Bang, according to an e-mail message from Mr. Deutsch that another NASA employee forwarded to The Times.

The Big Bang memo came from Mr. Deutsch, a 24-year-old presidential appointee in the press office at NASA headquarters whose résumé says he was an intern in the “war room” of the 2004 Bush-Cheney re-election campaign. A 2003 journalism graduate of Texas A&M, he was also the public-affairs officer who sought more control over Dr. Hansen’s public statements.

In October 2005, Mr. Deutsch sent an e-mail message to Flint Wild, a NASA contractor working on a set of Web presentations about Einstein for middle-school students. The message said the word “theory” needed to be added after every mention of the Big Bang.

The Big Bang is “not proven fact; it is opinion,” Mr. Deutsch wrote, adding, “It is not NASA’s place, nor should it be to make a declaration such as this about the existence of the universe that discounts intelligent design by a creator.”

It continued: “This is more than a science issue, it is a religious issue. And I would hate to think that young people would only be getting one-half of this debate from NASA. That would mean we had failed to properly educate the very people who rely on us for factual information the most.”

The fact that this additional censorship caused outrage in the scientific community can certainly be attributed to the religious censorship aspects of the declarations, but the to-do over the specific insertion of the word “theory” was particularly interesting to me. Nobody in the community would deny that the Big Bang is a theory. But it is a theory in the scientific sense in that it has been vetted by an overwhelming body of evidence.

Ironically, Deutsch, the Bush appointee, was trying to degrade and discredit the Big Bang theory by applying the plebian usage, which when written, still complied with how scientists would talk about it themselves. But the scientists knew what he meant to do. “It’s not what you said; it’s how you said it!”

Unfortunately for Deutsch, the evidence for the Big Bang is, quite literally, directly visible before our eyes. All anyone has to do is look up at night. Okay, they have to look carefully with the right telescopes and whatnot. But the fact that due to the finite speed of light, we can effectively and directly see backwards in time more than 14 billion years (by looking farther and farther away) all the way to a point about one minute after the enormous explosion that heralded the beginning of our universe as we know it, is one of the most profound and well-established scientific truths. It is an excellent theory in the strongest sense of the word.

Now all we have to do is properly educate the general public on the correct usage and definition of “theory” as we are using it scientifically to describe Evolution and The Big Bang and whatnot, and hope that people stop trying to cram political and religious agendas into gaps they mistakenly perceive in theories that are really beyond question.

We’ve managed to get most people to agree with the theories that the Earth isn’t the center of the solar system, or the Milky Way Galaxy, or even the Universe. And we’re now pretty unanimous on the theory that the Earth is not flat. Evolution and the Big Bang are in the same territory. All we need is a little more education to make that clear to more people.

Leave a comment

Filed under Astronomy, Politics, Science

National Science Foundation: Science is Hard

From the Onion. It must be true.

Leave a comment

Filed under Humor, Science

The Best Electronics "Toy" EVER!

Just yesterday I stumbled across a treasured bit of history while cleaning out the garage. It was a brochure I had picked up at the 1989 National Science Teacher’s convention in Atlanta. (That tells you the archeological depths plumbed in my latest foray) Despite the fact that I had seen neither hide nor hair of them for the last seventeen years, it turns out they still exist. I was overjoyed to reconnect with the small German company via Google and discover that their line of electronics kits are still available and have even expanded in number.

I have always felt that there has been a large, longstanding, and gaping hole in today’s educational system where electronics should be. It seems almost criminal to me that most children are never really introduced to the technology that has become the very foundation of modern society, telecommunications, computing, networking, media, and entertainment industries. Those who are introduced, rarely see a circuit more complicated than a battery and a light or motor until their undergraduate days. And by that time, the ranks of the interested have been so thinned that we have lost a majority of the potential audience and ranks of latent scientists and engineers.

There have certainly been significant barriers to administering an introductory electronics program to elementary and high school students, ranging from the complexity of interconnecting ever shrinking parts of ever increasing complexity to the hazards of extremely hot soldering irons in tiny hands. But these are functional barriers that tend to mask rather simple and fundamental concepts that could otherwise be approachable at a surprisingly young age. And while lamenting the situation, I had never managed to discover a way to practically surmount these barriers until I found Lectron, GMBH.

The Lectron kits are a wonder of fine German design and engineering unsurpassed in the educational materials market. (They are also pretty pricey, but worth every penny.) Each kit includes an extensive set of electronic components, each of which is individually packaged in a sturdy Lego-like plastic block with magnetized contacts and the industry-standard symbol for the part stenciled on the top face. The steel back-plate can be used as a ground plane to which the magnetized circuit blocks stick, and the process of building circuits is literally reduced to playing with blocks that naturally stick together.


The instructional and guide books are wonders of inspiration with hordes of example circuits. And while a little German reading skill could be helpful, assembly is just so darn simple that you don’t really need more than the example pictures. Any child that can build something with Legos can now build ever more complex electronic circuits with no other training or materials. They can build ANYTHING! (assuming you buy them the deluxe kit with enough pieces!) It comes complete with batteries, meters, resistors, capacitors, transistors, interconnect, LEDs, motors, switches, buttons, solar cells…damn near anything you can imagine.

Check out the range of circuits from a few of their example books:

A simple circuit to light an LED with two batteries.
A simple voltage divider with a meter

A small AM radio transmitter.

Digital logic circuitry.

A simple FM radio receiver.

Lectron pitches the intro kits as appropriate for children ages of 9 and over, but I suspect the simpler circuits and easy block assembly could be accessible starting at ages 5 and 6. In fact, I am ordering a kit for my four-year-old today, and if she doesn’t like it yet, my wife and I will play with it until she is ready.

As for schools, I should think every school in America and eventually the entire country’s economy could benefit strongly from having a dozen of these kits lying around for students to play with instead of shooting spit balls at each other. I might even be convinced to donate a few of them to worthy causes.


4 Comments

Filed under Education, Technology

Study Reports Teacher’s Gender Affects Learning

In the late seventies and early eighties when I was diligently avoiding work at my private high school, science, history, languages, art, and drama were co-ed classes, but home-room, English, math and PE classes were single-sex classes. Before long, however, the forces of political correctness, armed with a familiar chant of “separate is NOT equal,” drove the school to fully integrated co-ed classes with PE as the sole remaining hold-out. I remember feeling a pang of loss when I heard the news, but couldn’t really define why.

Oddly enough, the school now finds itself in a position where despite theoretical equal access to high-level science classes, not one single young lady enrolled in last year’s AP Physics class, which saw over thirty young men perform admirably on the AP test at the end of the school year. So access clearly isn’t the only problem.

In 1989, when I found myself a teacher at a completely co-ed public high school in southern California, I ultimately concluded that the single biggest distraction in the classroom was the opposite sex, and I would have welcomed the idea of teaching two separate physics classes, one to the boys and one to the girls. I struggled to reach both the young men and the women in the class, and found myself half-way through the first semester with the women’s grades starting to slip en-mass. I spent a couple of months trying to come up with different ways of reaching and inspiring the young ladies to no avail. The average girl’s GPA had slipped a whopping 9 points lower than the average boy’s grade by the second month of the final semester. By that time, I was loosing quite a lot of sleep over the issue.

Thankfully, I made a breakthrough when the class was studying electrostatics and simple circuits. Three of my best female students had teamed up to build, test and debug some of the simple battery-resistor-capacitor-transistor circuits I had designed for the class. halfway through the period one of them came to me and said, “Mr. Alvelda, I think we’ve put the circuit together properly but it just doesn’t seem to work.”

When I joined them at their lab bench to check their progress, I found some of the most meticulous and carefully constructed prototype circuitry I have ever seen to this day. But curiously, despite our classroom conversation about conductors and insulators, the young ladies had failed to strip the insulation off the ends of the interconnecting wires. My jaw was hanging open; it had never even occurred to me that someone might reach their teenage years without having assembled an electrical circuit, wire stripping and all. And I had never mentioned the critical step in the entire lab setup.

Of course, when I gently reminded the young ladies of our insulator/conductor discussions, and showed them how the wires were manufactured to allow connections only where you want them while preventing electrical shorts elsewhere, they caught on in a flash and had the circuit working flawlessly in the span of a few minutes.

That moment clearly illustrated to me that all of my assumptions about what kids should have know by the time they reached my class were colored by my own experience, with a father who had me building full-blown radios and computers by the time I was twelve. I had been speaking with a vocabulary and set of experiences much more in common with the young men, and failing to reach the women who did not have similar backgrounds. So I undertook a monumental effort to completely revise my entire Physics curriculum so that it assumed no prior knowledge whatsoever.

Within thirty days, the women’s grades started to recover, and by the end of the school year they ultimately surpassed the men’s grades due largely to a slightly more mature and disciplined approach to studying. I wondered to what extent other teachers have had similar experiences.

=========================================

From my own personal teaching experience, I wasn’t surprised to see the results of this controversial new study scheduled to appear today in “Education Next,” a quarterly journal published by the Hoover Institution. Thomas Dee, an Associate Professor of Economics at Swarthmore College, and a visiting scholar at Stanford University, has studied the effect of teacher gender on education to conclude that girls learn more from women and boys learn more from men.

Dee examined the performance of nearly 25,000 eighth-graders, the stage of development at which gender gaps in performance begin to arise. He found that with a female teacher, girls performed better (and boys performed worse) in science, social studies, and English, than if the teacher were male.

The effect on students attitude was also measurable. “In a class taught by a man, girls were more likely to say the subject
was not useful for their future. They were less likely to look forward
to the class or to ask questions. With a female teacher, boys were more likely to be seen as
disruptive. Girls were less likely to be considered inattentive or
disorderly.”

While obviously controversial, the study is consistent with the findings of the Third International Mathematics and Science Study [TIMSS]
that found, among other things, that the percentage of a country’s 12th grade boys who comprehend probability and statistics increases 1% for each 2% increase in that country’s male teachers.

With women comprising roughly 80% of the public school teaching force, and high-level math and physics classes skewed heavily towards male teachers, this is clearly an issue worth looking into.

1 Comment

Filed under Education

Static Images That Play With Your Rods (In Your Retina)

Believe it or not, this image is not actually animated. The effect you see is the result of the spatial patterns in the image interacting with the interconnected patterns of the photosensitive neurons in your Retina (of which, Rods and Cones figure prominently). Pretty trippy huh?

And more from Akiyoshi’s illusion Page :

If for some reason, you don’t notice any odd effects when looking at these images, note that they tend to work best at their full resolution. So just hop on over to Akiyoshi’s site through the link above to check them out in all their glory.



http://www.ritsumei.ac.jp/~akitaoka/sakuras2b.gif







1 Comment

Filed under Science