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This colorful view from NASA's Cassini mission is the highest-resolution view of the unique six-sided jet stream at Saturn's north pole known as "the hexagon." This movie, made from images obtained by Cassini's imaging cameras, is the first to show the hexagon in color filters, and the first movie to show a complete view from the north pole down to about 70 degrees north latitude.
Scientists can see the motion of a wide variety of cloud structures that reside within the hexagon in this movie. There is a massive hurricane tightly centered on the north pole, with an eye about 50 times larger than the average hurricane eye on Earth. (More information about that Saturn hurricane is at PIA14947.) Numerous small vortices are also present, which appear as reddish ovals. Some of these vortices spin clockwise while the hexagon and hurricane spin counterclockwise. Some of those smaller features are swept along with the jet stream of the hexagon, as if on a racetrack. The biggest of these vortices, seen near the lower right corner of the hexagon and appearing whitish, spans about 2,200 miles (3,500 kilometers), approximately twice the size of the largest hurricane on Earth.
The differences in this version of the movie, in which different wavelengths of light from ultraviolet to visible to infrared have been assigned colors, show a distinct contrast between the types of atmospheric particles inside and outside the hexagon. Inside the hexagon there are fewer large haze particles and a concentration of small haze particles, while outside the hexagon, the opposite is true. The jet stream that makes up the hexagon seems to act like a barrier, which results in something like the "ozone hole" in the Antarctic.
This movie shows a view from directly over the north pole, keeping up with the rotation of the planet so that all the motion seen on the screen is the motion of the hexagonal jet stream or the storms inside of it, without any added motion from the spinning of the planet itself. The original images were re-projected to show this polar view.
High-resolution views of the hexagon have only recently become possible because of the changing of the seasons at Saturn and changes in the Cassini spacecraft's orbit. The north pole was dark when Cassini first arrived in July 2004. The sun really only began to illuminate the entire interior of the hexagon in August 2009, with the start of northern spring. In late 2012, Cassini began making swings over Saturn's poles, giving it better views of the hexagon.
The eight frames of the movie were captured over 10 hours on Dec.10, 2012. Each of the eight frames consists of 16 map-projected images (four per color filter, and four filters per frame) so the movie combines data from 128 images total.
In this color scheme, scientists assigned red to the 0.750-micron part of the light spectrum (near infrared). This part of the spectrum penetrates the high-altitude haze layer to sense the top of tropospheric cloud deck. They assigned green to the 0.727-micron part of the light spectrum that senses the upper tropospheric haze (a near-infrared wavelength corresponding to a methane absorption band). They assigned blue to the sum of blue and ultraviolet broadband filters -- combined, this blue channel covers between 0.400 and 0.500 microns (covering very near ultraviolet to blue in visible light). This part of the spectrum is sensitive to small aerosols.
To human eyes, the hexagon and north pole would appear in tones of gold and blue. See PIA14945 for a still image of the area in natural color. [Reply]
What do you get when you mix the heart cells of a rat with silicone from breast implants and then sprinkle in a bit of gold and genetic engineering? No, not Trump's next trophy wife -- you actually get this incredible "living" robot. Developed by a team of researchers at Harvard University, the bio-engineered marvel looks, flexes and swims just like a tiny stingray.
The stingray-bot is made up of four distinct layers: a silicone substrate that forms its body, a skeletal system made of gold wire, a second layer of silicone that insulates the skeleton and, finally, 200,000 genetically-engineered rat cells. Those cells are designed to contract when exposed to a specific wavelength of light. When they do, the robot effectively swims in the same undulating manner as its namesake. What's more, the "biological life-form," as lead researcher, Kit Parker, describes it, automatically follows the light source as it swims through the nutrient-rich liquid that keeps its cells alive, allowing it to be remotely controlled.
The bio-bot can't survive outside of the lab yet. Even if it didn't need its specialized liquid, the rat cells have no immune system and would be immediately attacked by bacteria and fungal pathogens. Even so, Parker hopes that it will lead others to develop a complete, genetically-engineered heart, among other things.
"Roboticists and engineers can see different ways to use biological cells as building materials," Parker told Popular Mechanics. "Marine biologists can take a look to better understand why the muscle tissues in rays are built and organized the way they are." [Reply]
What do you get when you mix the heart cells of a rat with silicone from breast implants and then sprinkle in a bit of gold and genetic engineering? No, not Trump's next trophy wife -- you actually get this incredible "living" robot. Developed by a team of researchers at Harvard University, the bio-engineered marvel looks, flexes and swims just like a tiny stingray.
The stingray-bot is made up of four distinct layers: a silicone substrate that forms its body, a skeletal system made of gold wire, a second layer of silicone that insulates the skeleton and, finally, 200,000 genetically-engineered rat cells. Those cells are designed to contract when exposed to a specific wavelength of light. When they do, the robot effectively swims in the same undulating manner as its namesake. What's more, the "biological life-form," as lead researcher, Kit Parker, describes it, automatically follows the light source as it swims through the nutrient-rich liquid that keeps its cells alive, allowing it to be remotely controlled.
The bio-bot can't survive outside of the lab yet. Even if it didn't need its specialized liquid, the rat cells have no immune system and would be immediately attacked by bacteria and fungal pathogens. Even so, Parker hopes that it will lead others to develop a complete, genetically-engineered heart, among other things.
"Roboticists and engineers can see different ways to use biological cells as building materials," Parker told Popular Mechanics. "Marine biologists can take a look to better understand why the muscle tissues in rays are built and organized the way they are."
Basically, the scoop up water with their tongue and throw it at their face & hope for the best. I knew that was the method because of the gigantic puddle of water around the water dish my dogs leave. [Reply]
Originally Posted by Fish:
mix the heart cells of a rat with silicone from breast implants and then sprinkle in a bit of gold and genetic engineering? No, not Trump's next trophy wife
The other day I was amused to find a quote from Einstein, in 1936, about how hard it would be to quantize gravity: “like an attempt to breathe in empty space.” Eight decades later, I think we can still agree that it’s hard.
So here is a possibility worth considering: rather than quantizing gravity, maybe we should try to gravitize quantum mechanics. Or, more accurately but less evocatively, “find gravity inside quantum mechanics.” Rather than starting with some essentially classical view of gravity and “quantizing” it, we might imagine starting with a quantum view of reality from the start, and find the ordinary three-dimensional space in which we live somehow emerging from quantum information. That’s the project that ChunJun (Charles) Cao, Spyridon (Spiros) Michalakis, and I take a few tentative steps toward in a new paper.
We human beings, even those who have been studying quantum mechanics for a long time, still think in terms of a classical concepts. Positions, momenta, particles, fields, space itself. Quantum mechanics tells a different story. The quantum state of the universe is not a collection of things distributed through space, but something called a wave function. The wave function gives us a way of calculating the outcomes of measurements: whenever we measure an observable quantity like the position or momentum or spin of a particle, the wave function has a value for every possible outcome, and the probability of obtaining that outcome is given by the wave function squared. Indeed, that’s typically how we construct wave functions in practice. Start with some classical-sounding notion like “the position of a particle” or “the amplitude of a field,” and to each possible value we attach a complex number. That complex number, squared, gives us the probability of observing the system with that observed value.
Mathematically, wave functions are elements of a mathematical structure called Hilbert space. That means they are vectors — we can add quantum states together (the origin of superpositions in quantum mechanics) and calculate the angle (“dot product”) between them. (We’re skipping over some technicalities here, especially regarding complex numbers — see e.g. The Theoretical Minimum for more.) The word “space” in “Hilbert space” doesn’t mean the good old three-dimensional space we walk through every day, or even the four-dimensional spacetime of relativity. It’s just math-speak for “a collection of things,” in this case “possible quantum states of the universe.”
Hilbert space is quite an abstract thing, which can seem at times pretty removed from the tangible phenomena of our everyday lives. This leads some people to wonder whether we need to supplement ordinary quantum mechanics by additional new variables, or alternatively to imagine that wave functions reflect our knowledge of the world, rather than being representations of reality. For purposes of this post I’ll take the straightforward view that quantum mechanics says that the real world is best described by a wave function, an element of Hilbert space, evolving through time. (Of course time could be emergent too … something for another day.)
