Science Videos
Better than Myth Busters! These are great short videos exploring the world of science.
Clothes Make Not the Man, But Labels Do!
In a fascinating study, reported on in the Economist (Science and Technology section, April 2nd), a couple of researchers from the Netherlands experimented with clothing labels, actually clothes with and without them. Personally, I’ve never been big on wearing labelled clothing and it looks like I’ve been missing out on many benefits.
Depending upon the label, men wearing clothes with more expensive item labels rated higher than those without. When a designer logo appeared on a man pictured, photo shopped in, his status varied with label, for example Lacoste rated about point higher (4 out 5) versus Slazenger (3) and no label, which dropped it another .5 point or so. In a video study, a perspective job candidates rated higher if they were wearing similarly labelled clothes and even received higher salary recommendations, like +9%. The effect even works for charitable donations. Such effects have long been known in works of art, value rests in the signature. And I’ve always found more status in Marmot and Northface as opposed to REI, or JC Penny’s, but I never suspected the effect was so extensive. It’s worth a gander. The effect extends across the world of vertebrates.
Their study is reported in Evolutionary Human Behavior:
When the Exploratorium Started Out…
Staff list that was created by Frank Oppenheimer and the edited later that year.
This staff list comprises the staff on-hand for during my first year of employment at the Exploratorium.
It must be mentioned that Jackie Oppenheimer, wife and co-founder with Frank, managed and supervised the Exploratorium shop and gift store, She played an instrumental role in the development of floor graphics and early publications for the public, and served as Frank’s consul to the staff.
Michael Oppenheimer created a number of exhibits and worked closely with Pete Richards, but by April of 1972 had pretty much moved on to other venues.
Some names could not entirely be deciphered. But I think I transcribed most of them. Frank’s writing was frequently hard to read. Very early on, we had salaried employees and hourly employees and lots and lots of part time employees. All told there were 65 staff member , an increase of 15 that equaled 36 full-time equivalents. We’re at something approximating 400 FTE’s today.
Electricity Beneath Our Feet
The world generally divides between organisms that live in the light and those that don’t, and it’s actually not so much about the light but the molecules and atoms that donate, move and accept electrons. For us, and most of our well known companions, oxygen serves as the electron acceptor and carbon as the ever present electron donator, and life as we know it functions as electro-chemical conduit between the donor and acceptor atoms.
To speculate a bit, in the universe more generally, life facilitates the process of electron movement, which, in turn, endlessly drives its complex chemical machinery. (At least until the energy runs out.) On earth, green plants use sun light to reduce carbon from its oxidized state as carbon dioxide (CO2) into reduced stuff they’re made of (sugars, proteins, starch, and cellulose), an array of carbohydrates and all sorts of complex molecules. Animals and decomposers run this reduced carbon back the other way oxidizing it back to carbon dioxide. We call it food. The electro-chemical difference between these two states of oxidation of carbon powers life.
Below the Earth’s surface though the chemistry changes: reduced carbon and carbon dioxide predominant. Free oxygen becomes a rarity. Without the usual electron receiving oxygen, and all it wonderfully liberating energy, life creeps to a standstill. It typically doesn’t move very much, it’s generation times can sometimes be measured in thousands of years, rather than years or minutes, and only a very few multicellular compilations occur, and exotic chemistries prevail in a slow but steady venture.
Iron and sulfur become electron acceptors and donors, replacing oxygen, and carbon dioxide an electron receptor. In spite of the apparent differences the currency of the realm, as on the surface of the planet, is electrons and molecular states of energy. Despite these differences, it’s possible to think of life as one giant battery. Electrons moves and molecules change shape and act in a myriad precise of ways.
A unifying characteristic of life is it’s ability to harness and share the movement of electrons. Life’s smallest units are cells and virons. In a complex multicellular organism such as ourselves, we have all kinds of ways for moving electrons from one cell to another, and we’re in a steady-state of flux.
Beneath our feet, in the ground upon which we stand, things are a bit more complex. The cells are free and generally individualized. There typically isn’t a clearly defined path of circulation or communication. There may be billions of cells in a hand-full of soil. However, recent discoveries, by researchers like Ken Nealson suggest a more complex bit of bio-engineering. The cells of some bacteria, Shewanella oneidensis, for instance, have been observed to sprout tiny projections, nanometers in diameter, and 10′s of nanometers long. These hairy bacteria apparently use these tiny hairs to make electrical circuits and flow electricity from one chemical point to another, just like connecting life to a battery from which they power the chemistry of life, and this effort is between various single cells to form a more complex community of living organisms.
The interesting thing is that Ken Nealson, a researcher at USC worked with us years ago to create an exhibit with photobacteria based upon a marine bacteria commonly found in the stomach of the Orange Roughy fish, and freely in the ocean at far lower concentrations discovered Shewanella oneidensis. What’s interesting is that these bacteria don’t turn on their light until concentrations reach about 10 exp 7th cells per milliliter and extinguish at about 10 exp 9th.
The ingenuity of bacteria and life never ceases to amaze me.
Human Trails
Given all our GPS and trail marking technologies, it’s interesting to see the emergence of new forms of defining territories. Some are very provocative and others evocative. There’s one incredible hot spot I’ve never been to, such is the life of an SF area native.
Measuring Sea Level Is Not So Easy
In one of my recent posts, I referenced the fact the our new piers are about 41 inches above the high high tide of the bay, and I’m going to call that a meter. As someone never to be deterred in my un-ending quest for information, I’ve been reading and researching some of the things that affect sea level(s) on Earth and in turn the heights of the structures that we humans build with respect to the level of the sea.
One of the most surprising things turns out is that gravity, itself, plays an important role. Frozen water, large amounts of it, like say Greenland and Antarctica, have a greater mass because of ice, and that the gravity of these two masses measurably attract and raise the level of the nearby oceans. As they melt other parts of the ocean will rise. That’s quite a pull.
Additionally, and locally, a whole bunch of smaller effects come into play. Conferring with local geoclimatic scientists at the USGS and NOAA, revealed some other surprising effects: when a storm comes through it raises the local sea level by about 1 cm for each millibar of pressure drop (a 20 to 25 cm rise for a significant storm); there are on shore southerly winds that can raise it another 30 cm; there is the average annual ocean upwelling cycle along our coast that can add between 5-10 cm (in the fall and winter); and el niño thermal effects that can add about 20 cm.
I never would have expected sea level to vary so much. These variations and potential measurements sound like a whole bunch of great exhibits to me.
The take home message I get out of all this is that that the measured meter of clearance built into the height of our piers above the current sea level, just close enough, to high enough to keep them from getting wet, and not too much more. It is like a life’s “Red Queen” environmental effect, a laudable and rational rationale: build no more than absolutely necessary. Or as one zebra said to the other zebra when escaping from a lion, “I don’t have to be the fastest zebra in the herd, I just need to be faster than you.”
The upshot of all my observations and research is that as the sea level rises from the melt of the polar land ice, which accounts for about 30%-40% of the current sea level rise, that other factors such as thermal expansion as the oceans warm, coupled with a decrease in gravitational attraction of the polar ice, as well as the potential for more frequent and profound storms will gradually erode our current margin of safety. It won’t necessarily be a linear effect from year to year but one marked by transient events.
Given the current 3.5 cm rise in sea level per decade. I suspect that at this rate, which is by no means certain to be so low, that by 2050 the eightieth anniversary of the Exploratorium that it may well go below the surface of the bay from time to time. (And of course this is assuming that climate behaves in a linear fashion, for which, there is little evidence.) Admittedly, we have a relatively long time to deal this this, but I think it’s more certain than an earthquake.
Exhibit Diversity at the Exploratorium
Almost everyone that comes to the Exploratorium wants to know from where the ideas for exhibits come. Well, the sources are many. For example, a staff member building an image archive forwarded me a photo, and asked me what I could say about it, and it seems like an instructive example. Here’s the exhibit and subsequent story.
This exhibit underwent several variations before achieved its final look!
Taking Water Apart… circa 1989
First built in 1978. Always an outlandish piece of equipment.
Okay! It was built in two phases. I originally built and designed the exhibit (s). After a conversation with Frank Oppenheimer about electrolysis. Chemistry is really tough to do in a museum setting.
The original name was “Taking Water Apart and Putting Back Together with a Flame.” Many years later, it became “Ping Pong Ball Shooter” after we modified it to improve its visitor engagement and performance.
The beaker and flask on the right consisted of a custom build electrolytic cell with a refrigerated safety containment vessel. The cathode was a graphite rod and the anodes iridium oxide on titanium sheet metal. It took me a while to get the electrodes figured out. Using the system I could drive 35 amps of current through the 10% sulfuric acid electrolyte at 10 volts. This amount of electrolysis seemed to generate about 10 cc’s of pure hydrogen gas a minute (this is a good calculation to do and I’m just guessing here). In any case, it’s a lot of gas.
On the left side of the exhibit, we initially produced a colorless hydrogen flame with a slightly warmed platinum wire, it was a catalytic event, and a tiny but hot flame.
Much later, Randall Fontes––an exhibit builder/designer–– and I modified the flame part to shoot a ping pong ball up to the ceiling. A totally crazy loud bang that attracted thronging masses of school kids. The explosion was so loud that we had to install a motorcycle muffler to quiet the bang. The netting strung across the steel hoop typically caught the returning ball and reloaded the device, so visitors could relaunch the ball.
A story in KC’s book (Something Incredibly Wonderful Happens) about Frank picks up an interaction I had with Frank during its first phase of development. ”One little explosion and you haven’t worked on it for 6 months.” As I pointed out to Frank, I was the one that experienced the explosion and I wasn’t exactly trying to repeat it, and that I was getting a piece of glass made. (Tom Orr, who was a scientific glass blower, made the flask and subsequently came into the museum for many, many weekends as a volunteer glass maker and plied his trade to the delight of visitors.)