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James May's Man Lab [2/3]

0:52:10

silichip

12-09-2012

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James May's Man Lab [3/3]

0:58:55

silichip

12-09-2012

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James May's Man Lab [1/5]

0:58:59

silichip

12-09-2012

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James May's Man Lab [2/5]

0:58:50

silichip

12-09-2012

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James May's Man Lab [3/5]

0:59:00

silichip

12-09-2012

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James May's Man Lab [4/5]

0:58:55

silichip

12-09-2012

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James May's Man Lab [5/5]

0:59:13

silichip

12-09-2012

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Lightning: Nature Strikes Back

0:58:42

silichip

08-09-2012

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Super Hurricanes

0:19:37

silichip

08-09-2012

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How Large is the Universe?

0:20:13

silichip

08-09-2012

Comments: 1

When Will Time End?

0:21:15

silichip

08-09-2012

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Supermassive Black Hole in the Milky Way Galaxy

0:20:09

silichip

08-09-2012

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The Search For Earth-Like Planets

0:21:29

silichip

08-09-2012

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Voyage to Pandora: First Interstellar Space Flight

0:21:08

silichip

08-09-2012

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Venus: Death of a Planet

0:22:09

silichip

08-09-2012

Comments: 0

Cosmic Energy: Cold Sparks to Black Holes

$Watch this and other space videos at http://SpaceRip.comWhat's the hottest place in the universe? What's it like inside a Black Hole? This video climbs the power scales of the universe, from the coldest and bleakest reaches of our galaxy on out to the hottest and most violent places known. How and where do Earth and humanity fit within the immensely powerful scales that define our universe? All across the immense reaches of time and space, energy is being exchanged, transferred, released, in a great cosmic pinball game we call our universe. To see how energy stitches the cosmos together, and how we fit within it, we now journey through the cosmic power scales of the universe, from atoms nearly frozen to stillness. To Earth's largest explosions. From stars colliding, exploding, to distant centers of power so strange, and violent, they challenge our imaginations. Today, energy is very much on our minds, as we search for ways to power our civilization and serve the needs of our citizens. But what is energy? Where does it come from? And where do we stand within the great power streams that shape time and space? Energy comes from a Greek word for activity or working. In physics, it's simply the property or the state of anything in our universe that allows it to do work. Whether it's thermal, kinetic, electro-magnetic, chemical, or gravitational. The 19th century German scientist Hermann von Helmholtz found that all forms of energy are equivalent, that one form can be transformed into any other. The laws of physics say that in a closed system - such as our universe - energy is conserved. It may be converted, concentrated, or dissipated, but it's never lost.Humans today generate about two and a half trillion watts of electrical power. How does that stack up to the power generated by planet Earth? Deep inside our planet, the radioactive decay of elements such as uranium and thorium generates 44 trillion watts of power. As this heat rises to the surface, it drives the movement of Earth's crustal plates, and powers volcanoes. Remarkably, that's just a fraction of the energy released by a large hurricane in the form of rain. At the storm's peak, it can rise to 600 trillion watts. A hurricane draws upon solar heat collected in tropical oceans in the summer. You have to jump another power of ten to reach the estimated total heat flowing through Earth's atmosphere and oceans from the equator to the poles, and another two to get the power received by the Earth from the sun, at 174 quadrillion watts. Believe it or not, there's one human technology that has exceeded this level. The AN602 hydrogen bomb was detonated by the Soviet Union on October 30, 1961. It unleashed some 1400 times the combined power of the Nagasaki and Hiroshima bombs. With a blast yield of up to 57,000 tons of TNT, it generated 5.3 trillion trillion watts, if only for a tiny fraction of a second. That's 5.3 Yottawatts, a term that will come in handy as we now begin to ascend the power scales of the universe. To Nikolai Kardashev, a Level 2 civilization would achieve a constant energy output 80 times higher than the Russian superbomb. That's equivalent to the total luminosity of our sun, a medium-sized star that emits 375 yottawatts. However, in the grand scheme of things, our sun is but a cold spark in a hot universe. Look up into Southern skies and you'll see the Large Magellanic Cloud, a satellite galaxy of our Milky Way. Deep within is the brightest star yet discovered. R136a1 is 10 million times brighter than the sun. Now if that star happened to go supernova, at its peak, it would blast out photons with a luminosity of around 500 billion yottawatts. To advance to a level three civilization, you have to marshal the power of an entire galaxy. The Milky Way, with about two hundred billion stars, has an estimated total luminosity of 3 trillion yottawatts, a three followed by 36 zeros. To boldly go beyond Level 3, a civilization would need to marshal the power of a quasar. A quasar is about a thousand times brighter than our galaxy. Here is where cosmic power production enters a whole new realm, based on the physics of extreme gravity. It was Isaac Newton who first defined gravity as the force that pulls the apple down, and holds the earth in orbit around the sun. Albert Einstein redefined it in his famous General Theory of Relativity. Gravity isn't simply the attraction of objects like stars and planets, he said, but a distortion of space and time, what he called space-time. If space-time is like a fabric, he said, gravity is the warping of this fabric by a massive object like a star. A planet orbits a star when it's caught in this warped space, like a ball spinning around a roulette wheel.$

0:21:32

silichip

08-09-2012

Comments: 0

Is the Universe Infinite?

$Watch this and other space videos at http://SpaceRip.comExplore the biggest question of all... in 1080p. How far do the stars stretch out into space? And what's beyond them? In modern times, we built giant telescopes that have allowed us to cast our gaze deep into the universe. Astronomers have been able to look back to near the time of its birth. They've reconstructed the course of cosmic history in astonishing detail.From intensive computer modeling, and myriad close observations, they've uncovered important clues to its ongoing evolution. Many now conclude that what we can see, the stars and galaxies that stretch out to the limits of our vision, represent only a small fraction of all there is. Does the universe go on forever? Where do we fit within it? And how would the great thinkers have wrapped their brains around the far-out ideas on today's cutting edge? For those who find infinity hard to grasp, even troubling, you're not alone. It's a concept that has long tormented even the best minds.Over two thousand years ago, the Greek mathematician Pythagoras and his followers saw numerical relationships as the key to understanding the world around them. But in their investigation of geometric shapes, they discovered that some important ratios could not be expressed in simple numbers.Take the circumference of a circle to its diameter, called Pi. Computer scientists recently calculated Pi to 5 trillion digits, confirming what the Greeks learned: there are no repeating patterns and no ending in sight.The discovery of the so-called irrational numbers like Pi was so disturbing, legend has it, that one member of the Pythagorian cult, Hippassus, was drowned at sea for divulging their existence. A century later, the philosopher Zeno brought infinity into the open with a series of paradoxes: situations that are true, but strongly counter-intuitive. In this modern update of one of Zeno's paradoxes, say you have arrived at an intersection. But you are only allowed to cross the street in increments of half the distance to the other side. So to cross this finite distance, you must take an infinite number of steps.In math today, it's a given that you can subdivide any length an infinite number of times, or find an infinity of points along a line. What made the idea of infinity so troubling to the Greeks is that it clashed with their goal of using numbers to explain the workings of the real world.To the philosopher Aristotle, a century after Zeno, infinity evoked the formless chaos from which the world was thought to have emerged: a primordial state with no natural laws or limits, devoid of all form and content.But if the universe is finite, what would happen if a warrior traveled to the edge and tossed a spear? Where would it go? It would not fly off on an infinite journey, Aristotle said. Rather, it would join the motion of the stars in a crystalline sphere that encircled the Earth. To preserve the idea of a limited universe, Aristotle would craft an historic distinction.On the one hand, Aristotle pointed to the irrational numbers such as Pi. Each new calculation results in an additional digit, but the final, final number in the string can never be specified. So Aristotle called it$

0:23:54

silichip

08-09-2012

Comments: 0

Alien Planets & Eyeball Earths: The Search for Habitable Planets

0:24:27

silichip

08-09-2012

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Attack of the Sun

0:24:01

silichip

08-09-2012

Comments: 0

Saturn's Mysterious Moons

$Watch this and other space videos at http://SpaceRip.comWatch in high-resolution 1080p. Launched three years before the new century... a spacecraft wound its way through the empty reaches of the solar system. On Earth, its progress was little noted, as it swung twice by the planet Venus, then our moon. And Earth. The asteroid belt. And Jupiter.Almost seven years later, on the first of July 2004, the Cassini probe entered the orbit of Saturn. It then began to compile what has become one of the greatest photographic collections of all time, of a giant gas planet, surrounded by colorful rings, guarded by a diverse collection of moons, and millions of tiny moonlets. Within this record, is a trail of clues... pointing to the energy sources and complex chemistry needed to spawn life. What are these mysterious worlds telling us about the universe, and Earth? In the outer reaches of the solar system, a billion and a half kilometers from the Sun... there is a little world known as Enceladus. Nearly all of the sunlight that strikes its icy surface is reflected back into space, making it one of the brightest objects in the solar system.At its equator, the average temperature is minus 198 degrees Celsius. It can rise about 70 degrees higher in grooves that stretch across the south pole like tiger stripes. Looming over it is the giant planet Saturn.In myth, Saturn - the Roman name for the primal Greek God Chronos - was the youngest son of Gaia, or Earth, and Uranus, sky. Wielding a scythe provided by his mother, the story goes, Saturn confronted his abusive father, castrating him. The blood of Uranus flowed into the seas, fertilizing the Earth and giving rise to Enceladus and other giant offspring. Saturn's moon Enceladus has its own tangled story. In 2005, the Cassini spacecraft spotted plumes of water vapor shooting out into space from its south pole. More recent close encounters have revealed jets of water, flavored by slightly salty chemical compounds, spewing out from vents in the rough, cracked polar terrain. That may mean that Enceladus harbors a remarkable secret below its frigid surface: A liquid ocean, and perhaps, a chemical environment that could spawn simple life forms. It's not the only promising stop in the realm of Saturn. The moon Titan is often said to resemble Earth in its early days. It is lined with volcanoes and a hazy atmosphere rich in organic compounds. While Enceladus is the size of Great Britain, Titan is ten times larger, 50% larger than our moon, and the second largest moon in our solar system.We've known about Titan since the astronomer Christian Huygens discovered it in 1655, and Enceladus since William Herschel spotted it in August 1789, just after the start of the French Revolution. Scientists began to investigate these moons in earnest with the launch of the two Voyager spacecraft in 1977. The lineup of outer planets in the solar system allowed the spacecraft to fly past each of them.They disclosed new details about their magnetic fields, atmospheres, ring systems, and inner cores. But what really turned heads were the varied shapes and surfaces of their moons. They've all been pummeled over the millennia by wayward asteroids and comets. A few appear to be sculpted by forces below their surfaces. Neptune's largest moon Triton has few craters. It's marked with circular depressions bounded by rugged ridges. There are also grooves and folds that stretch for dozens of miles, a sign of fracturing and deforming. Triton has geysers too, shooting some five miles above the surface. But on this frigid moon -- so far from the Sun -- the liquid that spouts is not water but nitrogen. Tiny Miranda, one of 27 known moons that orbit Uranus, wears a jumbled skin that's been shaped and reshaped by forces within. Jupiter's moon Io -- orbiting perilously close to the giant planet is literally turning itself inside out. Rivers of lava roll down from open craters that erupt like fountains. Flying by Europa, Voyager documented a complex network of criss-crossing grooves and ridges. In the 1990s, the Galileo spacecraft went back to get a closer look. It found that Europa's surface is a crazy quilt of fractured plates, cliff faces and gullies... amid long grooves like a network of superhighways. How did it get like this? Then, heat rising up through a subsurface ocean of liquid water cracks, and shifts, and spreads the icy surface in a thousand different ways. Europa's neighbors, Callisto and Ganymede, show similar features, suggesting they too may have liquid oceans below their surfaces. Crossing outward to Saturn, Voyager found a similar surface on the moon Enceladus. So when the Cassini spacecraft arrived in 2004, it came looking for answers to a range of burning questions: if this moon and others have subsurface oceans? Do they also have the ability to cook up and support life? And what could they tell us about the origin of life throughout the galaxy?$

0:25:15

silichip

08-09-2012

Comments: 0

Mars: World That Never Was