Yesterday the Air Force tested a Boeing-built hypersonic "scramjet" called the X-51a "Waverider." It worked pretty well, apparently, tearing along at 5 times the speed of sound for three and a half minutes. They hoped to hit Mach 6, but a glitch interfered. Ah, well, one must walk before one can run, I suppose.
So what? This isn't the fastest machine ever built. Rockets have been going faster than that for years. On re-entry the Space Shuttle comes down at something like Mach 40 before burning off that speed in the upper atmosphere.
Ah, but the Waverider (which, I must admit, sounds like a high-tech surfboard) isn't a rocket. It's an air-breathing supersonic ramjet. Someday its remote descendants could be true "spaceplanes," taking off from a runway, accelerating to hypersonic speeds in the air before switching on rockets to climb into orbit. Its more immediate descendants could be awesomely powerful cruise missiles, zipping past defenses too quickly to be stopped.
If the Air Force is ever strapped for money to develop this further, I suggest putting in a passenger compartment and charging a million bucks or so for a ride.
As a man sitting behind a desk once put it, "We are all interested in the future, for that is where you and I will spend the rest of our lives."
Well, now Scientific American has put together a groovy interactive info-cyber-graphic-thingy exploring a dozen potential Big Events which would radically change the world. Some of them are likely, some are remote, some are probably inevitable, some could happen tomorrow.
But there's one Big Event which is missing from this list. The unlucky Number 13 is, quite simply, The Thing Nobody Expects. All the items on the SciAm list are imaginable, more or less by definition. The biggest change will come from something which catches everybody by surprise.
The former Secretary of Defense, Donald Rumsfeld, once famously answered a press conference question by explaining that there are "known knowns" (things we know we know), "known unknowns" (things we know we don't know), and "unknown unknowns" (the things we don't know, and don't know we don't know).
In 2050 I expect we will look back at this list and say "it was inevitable that this one, that one, and the other one would happen -- but how could they miss [X]? It was obvious!"
(Hat tip to io9 for the Scientific American story.)
Second, interesting findings about agriculture: birds prefer conventional crops, rather than organic agriculture. (Via, um, somebody. Can't remember where I found this. If it's you, let me know and I'll credit you.)
We all know Archaeopteryx is the earliest known bird -- a small dinosaur with wings, first found in very fine-grained sedimentary rock in Germany, which preserved the imprint of ancient feathers.
Dr. Robert Nudds and Dr. Gareth Dyke have been studying the mechanics of Archaeopteryx flight and have discovered some interesting differences in the structure of the ancient proto-bird's feathers. Unlike modern birds, Archaeopteryx had feathers with a fairly narrow central quill, and it must have been solid instead of hollow, or the feathers would not have been strong enough to withstand the forces generated in flight. In particular, flapping must have been almost impossible for Archaeopteryx, suggesting it was a glider (at best).
Really, this shouldn't come as a surprise. One would realistically expect early birds to be lousy fliers, and only after 70 million years of improvement do we see the amazing feats of modern birds. Evolution, and all that.
The mightiest planet in the Solar System must have really done something wrong, because it has lost one of its stripes. An amateur astronomer in Australia first spotted the change as Jupiter emerged from the Sun's glare this spring. The entire reddish Southern Equatorial Belt has disappeared. To give some scale, that's a cloud formation about 300,000 miles long and three times as wide as the Earth. If you know where it is, give the IAU a call.
Exactly why this has happened is anyone's guess. The planetary scientists are muttering about changes in heat flow, but for now the real answer is a shrug and a blank look. It's a pity the Galileo spacecraft wasn't around to observe the change. Having a camera on orbit watching stuff like this in real time would cut down a lot on the embarassed shrugging and head-scratching.
Of course, fans of Arthur C. Clarke know what's going on when Jupiter starts acting weird in 2010. It's those pesky Monoliths again.
You can’t always believe your
eyes. Poets may call them the window to the soul, but they’re really
specialized light and motion sensors attached to neural networks deep in your
brain. Your brain does the actual work of ‘seeing,’ and it’s remarkable how
easily it can be fooled.
Fundamentally, that’s what a
visual illusion is: your brain, fooled into perceiving motion or color where it
doesn’t really exist. But this also means illusions are more than simple parlor
tricks –they’re experiments in perception that can help neurologists and vision
scientists tease out what’s going on inside the brain. And that’s what makes
the annual contest for the Best Visual Illusion of the Year so exciting.
Working from newly-developed illusions submitted by scientists from all over
the world, a team of experts (including one magician) have selected what they
believe to be the 10 best entries. Tonight, at 5 pm Eastern time, a live
audience in Naples, Florida will watch the ten finalists present their illusions
and vote for the winners of the First, Second, and Third prizes.
Even if you can’t be there,
you can watch the illusions after the gala – they’ll be online on the Neural Correlate Society’s
contest site. And you can see which perception-changing
exercises moved the audience. Literally or not.
UPDATE: 5/12/10: The winner? Koukichi Sugihara's origami magnetic slope illusion. Want to make it? Here are instructions.
There's a huge new dam project in northern Alberta -- a structure 850 meters long, which will flood portions of a Canadian national park. But curiously, there is no opposition to this dam. Environmental groups are mysteriously silent. Were they paid off? Is this a super-secret Canadian government operation? Who's behind this gigantic construction project?
Beavers. You know, the furry buck-toothed guys with the pond fixation. In this case, apparently several generations of beavers have worked to build and maintain this gigantic dam. Hooray for the beavers, and bad luck on any other species whose habitat was destroyed by their efforts.
It does bring up a question, though: why are the structures built by beavers and other organisms considered "natural" but Hoover Dam is not? Sure, Hoover Dam is big, but the Great Barrier Reef is bigger, and it's made by coral polyps. Heck, coral have built entire islands in the ocean. They make huge changes to the ocean environment -- how come their kind of change is part of the natural order of things, but changes made by one kind of great ape are somehow different?
An archaeologist and a hydraulic engineer from Penn State have made a fascinating discovery at the Mayan city of Palenque. Apparently at least one of the aqueducts built by the ancient Mayans to carry water into the city was designed to increase water pressure, narrowing along its length to maximize the pressure at the bottom end. You can read the University press release here (or in virtually unaltered form in any of the news stories about the discovery). This seems to be the first known Mayan waterway making use of hydraulic principles to control water pressure, and suggests they had a much better understanding of the subject than anyone realized.
What was it for? Well, there may have been a practial reason -- perhaps the water went up again into some now-vanished structure in the city. Or maybe it was a fountain. Underground wells and waterways were vitally important to the Mayans, and had religious significance as well. A jet of water shooting up 20 feet from the ground would be really impressive, and the height of the fountain would be a good way to tell how much water is available for irrigation in a given season.
Or maybe the Mayans built the world's first water theme park. They were a very advanced civilization, you know. Had to pass the time somehow while waiting for the calendar to run out.