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Artist Scott Garner gives us a depiction of a bowl of fruit on a table, named “Still Life.” But this interactive artwork is anything but still! Link -via The Daily What Geek
Earth may be round, but not its gravitational field! After two years in orbit, the European Space Agency’s Gravity Field and Steady-State Ocean Circulation Explorer satellite has revealed the clearest picture of earth’s gravity-field map:
The geoid is the surface of an ideal global ocean in the absence of tides and currents, shaped only by gravity. It is a crucial reference for measuring ocean circulation, sea-level change and ice dynamics – all affected by climate change.
Hit play or go to Link [YouTube]
In the famous 1971 footage from Apollo 15, astronaut David R. Scott dropped a hammer and a feather at the same time on the surface of the Moon, thus confirming Galileo’s hypothesis that gravity accelerates all objects at the same rate, regardless of mass or composition:
Undoubtedly that has been hammered into your brain since grade school. So, how do you explain this neat little video from the clever folks over at MIT:
Two wood boards are connected by a hinge. A small cup is mounted near one end of the upper board with a tee for a ball on the end. The board is lifted to a certain height, and when released the ball ends up in the plastic cup. This shows that the board has moved farther than the ball in the same period of time.
To see the video, visit the MIT News Multimedia website: Link – via Science2.0
So, the hinged plank has to travel in an arc, which is longer than the straight path that the ball falls through in order for the ball to fall into the cup. Notice that the plank hits the tabletop before the ball. Assuming air resistance doesn’t come into much play (after all, the plank has more surface area than the ball) Does this mean that gravity affects the plank more than the ball? Is Galileo wrong?
Yesterday, Neatorama told you that time may be slowing down. Today, we’ll tell you that gravity doesn’t really exist.
Well that’s what Erik Verlinde, a string theorist and professor of physics at the University of Amsterdam, thinks:
“For me gravity doesn’t exist,” said Dr. Verlinde, who was recently in the United States to explain himself. Not that he can’t fall down, but Dr. Verlinde is among a number of physicists who say that science has been looking at gravity the wrong way and that there is something more basic, from which gravity “emerges,” the way stock markets emerge from the collective behavior of individual investors or that elasticity emerges from the mechanics of atoms. [...]
Dr. Verlinde’s argument turns on something you could call the “bad hair day” theory of gravity.
It goes something like this: your hair frizzles in the heat and humidity, because there are more ways for your hair to be curled than to be straight, and nature likes options. So it takes a force to pull hair straight and eliminate nature’s options. Forget curved space or the spooky attraction at a distance described by Isaac Newton’s equations well enough to let us navigate the rings of Saturn, the force we call gravity is simply a byproduct of nature’s propensity to maximize disorder.
Neil Fraser wondered if a lava lamp would still work in the higher gravity environment of Jupiter. How such a question ever occurs to anyone is a matter of wonder in itself, but Fraser went ahead and built a ten-foot wide centrifuge in his living room to conduct the experiment to answer his question.
The centrifuge is a genuinely terrifying device. The lights dim when it is switched on. A strong wind is produced as the centrifuge induces a cyclone in the room. The smell of boiling insulation emanates from the overloaded 25 amp cables. If not perfectly adjusted and lubricated, it will shred the teeth off solid brass gears in under a second. Runs were conducted from the relative safety of the next room while peeking through a crack in the door.
Highlight this text for a spoiler: Yes, the lava lamp worked in 3G. Link -via Digg
Go get your protective tin foil hat, because you’re going to need it. German scientists have been trying to understand why their equipment that measures gravitational waves has been picking up a particular sound. One possible answer that they’ve come up with is that the entire universe is a holographic illusion:
For many months, the GEO600 team-members had been scratching their heads over inexplicable noise that is plaguing their giant detector. Then, out of the blue, a researcher approached them with an explanation. In fact, he had even predicted the noise before he knew they were detecting it. According to Craig Hogan, a physicist at the Fermilab particle physics lab in Batavia, Illinois, GEO600 has stumbled upon the fundamental limit of space-time – the point where space-time stops behaving like the smooth continuum Einstein described and instead dissolves into “grains”, just as a newspaper photograph dissolves into dots as you zoom in. “It looks like GEO600 is being buffeted by the microscopic quantum convulsions of space-time,” says Hogan.
If this doesn’t blow your socks off, then Hogan, who has just been appointed director of Fermilab’s Center for Particle Astrophysics, has an even bigger shock in store: “If the GEO600 result is what I suspect it is, then we are all living in a giant cosmic hologram.”
The idea that we live in a hologram probably sounds absurd, but it is a natural extension of our best understanding of black holes, and something with a pretty firm theoretical footing. It has also been surprisingly helpful for physicists wrestling with theories of how the universe works at its most fundamental level.
The holograms you find on credit cards and banknotes are etched on two-dimensional plastic films. When light bounces off them, it recreates the appearance of a 3D image. In the 1990s physicists Leonard Susskind and Nobel prizewinner Gerard ‘t Hooft suggested that the same principle might apply to the universe as a whole. Our everyday experience might itself be a holographic projection of physical processes that take place on a distant, 2D surface.
This post gives you a crash course in gravity, specifically how gravity affects the way we travel to (or don’t travel to) other planets.
The more massive and more compact your planet is, the harder it is to get off of. Something like the Moon, which is only about 1.2% of the mass of the Earth but 27% of the Earth’s radius, is way, way easier to escape from than the Earth. To escape from the Earth’s gravity, you need to reach a speed of 40,000 km/hr (25,000 mph) from the Earth’s surface. To escape from the Moon, on the other hand, you only need to reach 8,600 km/hr (5,400 mph).
This explains why it would be so much easier to travel to one of the moons of Mars than to Mars itself, due to the ease of traveling back home from those places. Link
Charles Q. Choi of Live Science writes that scientists working for NASA used a superconducting magnet that simulates some of the effects of gravity to lift a mouse into the air. The agency has been working on such technology in the hope of alleviating the bone decay that would affect astronauts in zero-gravity environments for prolonged periods of time:
Scientists working on behalf of NASA built a device to simulate variable levels of gravity. It consists of a superconducting magnet that generates a field powerful enough to levitate the water inside living animals, with a space inside warm enough at room temperature and large enough at 2.6 inches wide (6.6 cm) for tiny creatures to float comfortably in during experiments….
Repeated levitation tests showed the mice, even when not sedated, could quickly acclimate to levitation inside the cage. After three or four hours, the mice acted normally, including eating and drinking. The strong magnetic fields did not seem to have any negative impacts on the mice in the short term, and past studies have shown that rats did not suffer from adverse effects after 10 weeks of strong, non-levitating magnetic fields.
“We’re trying to see what kind of physiological impact is due to prolonged microgravity, and also what kind of countermeasures might work against it for astronauts,” Liu said. “If we can contribute to the future human exploration of space, that would be very exciting.” They are now applying for funding for such research with their levitator.
Link via Popular Science
Image: U.S. Department of Energy
Erin Finnegan and Noah Fulmor of New York City said their wedding vows in a memorable way: in zero gravity! The ceremony took place Saturday inside a specially equipped aircraft flying in parabolic arcs to simulate the effects of space. This kind of ride is sometimes called “the vomit comet”, and is used for astronaut training.
Mr Fulmor, whose tuxedo tails were specially stiffened so they would not float out of control, admitted he had trouble lining up his lips for the all-important wedding kiss.
“The physics of the first kiss were off. I could feel where I was going, I knew where I needed to be, but it was hard to reconcile the differences,” he said.
“Noah knocked into my nose and I thought it would bleed,” Ms Finnegan said.
From Modern Mechanix, one of my favorite blogs, here’s the Swami, a simple pattern you can cut out on a piece of plywood that will let you defy gravity!
As mystifying as the Indian rope trick, this magic marvel defies the laws of gravity.
PROBABLY Isaac Newton was right; but you couldn’t prove it with this gadget. It just seems to work contrary to all laws of gravity.
Swami, by itself, reacts like any other object: supported at one end only—it falls. But, add a fairly heavy belt, as shown in the photo, and it will not only stay up but actually take quite a bit of extra pressure to make it tilt down, even slightly.
We won’t tell you how or why it works. That is part of the mystery. Go ahead and make one and try to find out for yourself. You’ll be truly amazed.
This is SO going to my ever growing list of "to-do one day" projects: Link
Relax, take a deep breath, and give puzzle game Perfect Balance a go. As the name implies, you need to try to get a collection of shapes to balance perfectly on a base structure.
There are 80 levels in total. Prepare for frustration.
Link – via onelargeprawn
