EP01【Standing Up in the Milky Way】
Jupiter's Great Red Spot, a hurricane three times the size of our whole planet, has been raging for centuries.
The crown jewel of our Solar System, Saturn, is ringed by freeways of countless orbiting and slowly tumbling snowballs, every snowball, a little moon.
Cosmic horizon like below. But beyond that horizon lie parts of the universe that is too far away. There hasn't been enough time in the 13.8 billion year history of the universe for their light to have reached us. Maybe all of these(stars galaxies clusters…) in our observable universe is but one tiny bubble in an infinite ocean of other universe, a multiverse, universe upon universe. Worlds without end.
The cosmic calendar begins on January 1st with the birth of our universe. Every month represents about a billion years, with every day nearly 40 million years.
January 1st, the Big Bang. Our entire universe emerged from a point smaller than a single atom. Space itself exploded in a cosmic fire, launching the expansion of the universe and giving birth to all the energy and all the matter we know today.
On January 13th, these stars coalesced into the first small galaxies. These galaxies merged to form still larger ones, including our own Milky Way, which formed about 11 billion years ago, on March 15th of the cosmic year.
Our sun will rise from the ashes of other stars. Those lights flashing like paparazzi, each one is a supernova, the blazing death of a giant star. Stars die and are born in places like this one, a stellar nursery. They condense like raindrops from giant clouds of gas and dust. They get so hot that the nuclei of the atoms fuse together deep within them to make the oxygen we breathe, the carbon in our muscles, the calcium in our bones, the iron in our blood, all of it was cooked in the fiery hearts of long-vanished stars. Everyone is made of star stuff. This star stuff is recycled and enriched, again and again, through succeeding generations of stars.
Our Sun's birthday is August 31st, four and a half billion years ago. As with the other worlds of our Solar System, Earth was formed from a disk of gas and dust, orbiting the newborn Sun, repeated collisions produced a growing ball of debris. The Earth took one hell of a beating in its first billion years. Fragments of orbiting debris collided and coalesced until they snowballed to form our Moon. The Moon is a souvenir of that violent epoch. If you stood on the surface of that long ago Earth , the Moon would have looked a hundred times brighter. It was ten times closer back then, locked in a much intimate gravitational embrace. As the Earth cooled, seas began to form. The tides were a thousand times higher then. Over the eons, tidal friction within Earth pushed the Moon away.
Life began on September 21st, three and a half billion years ago on our little world. By November 9th, life was breathing, moving, eating, responding to its environment. On December 17th, life in the sea really took off and it was exploding with a diversity of larger plants and animals. Tiktaalik was one of the first animals to venture onto land. The first flowers bloomed on December 28th. As these ancient forests grew and died and sank beneath the surface, their remains transformed into coal. 3 million years later, we humans are burning most of that coal to power and imperil our civilization. The dinosaurs might still be here if the asteroid missed the Earth. What a good example of the extreme contingency the chance nature of existence. We humans only evolved without the last hour of the last day of the cosmic year. 23:59:46 ,all of recorded history occupies only the last 14 seconds. All those kings and battles, migrations and inventions, wars and loves, everything in the history books happened in the last seconds of the Cosmic Calendar.
The scientific method is so powerful that in a mere four centuries it has taken us from Galileo's first look through a telescope at another world to leaving our footprints on the Moon.
EP02【Some of the Things That Molecules Do】
Artificial selection, turning wolves into dogs and the wild grasses into wheat and corn was the first time we human took evolution into our own hands.
The proteins called kinesin are part of the transport crew that's busy moving cargo around cell. How alien they seem.
If life has a sanctuary, it's here in the nucleus which contains our DNA, the ancient scriptures of our genetic code. And it's written in a language that all life can read. DNA is a molecule shaped like a long twisted ladder or double helix. The rungs of the ladder are made of four different kinds of smaller molecules. These are letters of the genetic alphabet. Particular arrangements of those letters spell out the instructions for all living things, telling them how to grow, move, digest, sense the environment , heal and reproduce. The DNA double helix is a molecule machine, with about 100 billion parts called “atoms”. There are as many atoms in a single molecule of your DNA as there are stars in a typical galaxy. We are, each of us, a little universe.
Mutations are entirely random and happen all the time but the environment rewards those that create the chance for survival. It naturally selects the living things that are better suited to survive. And that selection is the opposite of random.
An animal can live in boiling water or in solid ice, can go ten years without a drop of water and can travel naked in the cold vacuum and intense radiation of space and will return unscathed. The tardigrade or water bear. It's equally at home atop the highest mountains and in the deepest trenches of the sea. And in our backyard where they live among the moss in countless numbers.
Titan is the only other world in the solar system where it ever rains. It has rivers and coastlines and hundreds of lakes, which carve valley into the landscape. Whether life might swim in Titan's hydrocarbon lakes? (the river is made of methane and ethane which form natural gas on earth and water is frozen hard as rock to the landscape and mountains)
EP03【When Knowledge Conquered Fear】
When our comet reaches the inner Solar System, heat from the Sun bakes it. A beautiful transformation begins, the barren sooty iceberg now sports a glowing halo and a tail. During the 40,000 generations of humanity, there must have been roughly 100,000 apparitions of a bright comet. For all time, the best we could do was to look up in helpless wander.
Newton's Principal Mathematica set us free in another way by finding the natural laws governing the comings and goings of comets. He decoupled the motions of the heavens from their ancient connections to our fears.
If Halley hadn't been standing next to Newton for all those years, perhaps the world would remember him for his own accomplishments and discoveries. Discovering a comet is actually one of the few things that Halley never did. What he did includes First map of Earth's magnetic field, being businessman for diving bell to a flourishing commercial salvage operation, weather map indicating prevailing winds and so on.
Halley discovered the first clue to a magnificent reality: all the stars are in motion, streaming past each other, rising and falling like merry-go-round horses in their Newtonian dance around the center of our galaxy.
For millennia, comets had been props for mystics who considered them to be merely omens of human events. Halley shattered their monopoly beating them at their own game that no scientist had ever played before, prophecy. Halley stated flatly that the comet would return at the end of 1758 from a particular part of sky following a specific path. There is hardly a prophecy attempted by the mystics that ever even strives for comparable precision.
That's Halley's Comet, out here at the edge of the Solar System. It's just a big hunk of ice and rock in space. Halley's Comet is in free fall around the Sun by gravity and keep moving around the Sun by orbital momentum.
Every 76 years since, when Halley's Comet returns to our skies, sunlight will warm up the ice on its surface once again setting loose the dust and gases trapped within. Halley's Comet most recently visited our neighborhood back in 1986. And if you're seeing this in 2061, then you'll know it's back. May you feel the wander of all those who came before you and none of fear. Newton's laws made it possible for Edmond Halley to see some 50 years into the future and predict the behavior of a single comet.
One last prophecy, using nothing more than Newton's laws of gravitation, we astronomers can confidently predict that several billion years from now, our home galaxy, the Milky Way will merge with our neighboring galaxy Andromeda. Because the distances between the stars are so great compared to their size, few if any stars in either galaxy will actually collide. Any life on the worlds of that far-off future should be safe but they would be treated to an amazing billion-year-long show, a dance of a half a trillion stars to music first heard on one little world by a man who had but one true friend.
EP04【A Sky Full of Ghosts】
Every star is a sun as big as bright as our own. Just imagine how far away from us you'd have to move the sun to make it appear as small and faint as a star. The light from the star travels very fast, faster than anything, but not infinitely fast. Some stars are so far away, it takes eons for their light to get to Earth. By the time the light from some stars to get here, they are already dead. For those stars, we see only their ghosts. We see their light but their bodies perished long long ago. A telescope is a time machine. We cannot look out into space without seeing back in time. In one second, light travels 300,000 kilometers. That's nearly the distance from the earth to the moon. So the moon is about one light-second away. The next time you look at the moon you'll be seeing one second into the past.A light-year is the yardstick of the cosmos. A single one is nearly ten trillion kilometers. It's the distance light travels in a year. The nearest star to the sun, Proxima Centauri is a little more than four light-year away from earth . The oldest light is very faint, a pale ghost in the night. The red blob is one of the oldest galaxies we've ever seen, 13.4 billion year-old starlight captured by the Hubble Space Telescope.(very first generation of stars)(very first generation of stars)(very first generation of stars)
“Thou shalt not add my speed to the speed of light.” Speed of light is constant relative to everything else and nothing can ever catch up with light. Traveling close to the speed of light is kind of an elixir of life because your biological clock slows down relative to those you leave behind. This phenomenon may provide us humans who only live for a century or so a practical mean to travel to the stars where the magic show of spacetime really gets crazy.
At millions of g's, even light bows to gravity. The light still moves at its constant speed but it cannot escape. Michell's dark star, our black hole. When giant stars exhaust their nuclear fuel, they can no longer stay hot enough to fend off the inward pull of their own gravity. The most massive stars collapse into darkness leaving only their gravity behind. This black hole enshrouds the shrunken corpse of a supergiant star. The star itself has shriveled into something even smaller than this darkness, only 64 kilometers wide .
Cygnus X-1 is the first black hole ever discovered. In X-ray light, we lost sight of the blue star because its surface is a tepid 30,000 degree. But the disk of gas around the black hole glowed brilliantly in X-ray at 100 million degrees. Many stars have close companions forming a binary star system but if one member of such a pair is enormous and the other is compact, the small star can drain and consume the atmosphere of its larger sibling. This neurotic relationship can last for millions of years. The atmosphere of the larger was being siphoned onto a glowing hot accretion disk that revolves around and spirals into a black hole. The overwhelming gravity was accelerating the blue star's gas into a death spiral crossing the spacetime boundary never to be seen again .The fateful boundary that separates a black hole from the rest of the universe is called an event horizon. From our point of view, the substance in the disk slows down as it approaches the event horizon never quite reaching it. But if you were riding on that spiraling gas, you would sail past the event horizon in a matter of seconds into the undiscovered country from which no traveler returns.
Einstein discovered that space and time are just two aspects of the same thing, spacetime. Spacetime itself can deform enough to carry you anywhere at any speed. Black holes may very well be tunnels through the universe. On this intergalactic subway system you can travel to the farthest reaches of spacetime or you might arrive in someplace even more amazing. The phenomenal gravity of a black hole can wrap the space of an entire universe inside it. When a giant star collapses to make a black hole, the extreme density and pressure at the center mimic the big bang which gave rise to our universe. And a universe inside a black hole might give rise to its own black holes and those could lead to other universes.
Photography is a form of time travel. A ghost preserved by light. It's not hard to imagine that in near future we'll be able to capture the past in all three dimensions. We'll be able to step inside a memory.
"He broke through the walls of heaven."
EP05 【Hiding in the light】
Light waves of different lengths from the sun strike the earth, the petals of these particular flowers absorb all the low energy, long red wavelengths of light. But the petals reflect the shorter, high energy blue wavelengths. That interaction between starlight and petal or water or Van Gogh is what makes blue. The longest waves, the ones we see as red have the lowest energy. Color is the way our eyes perceive how energetic light waves are. A sunset, a flag, the eyes of your beloved, that shiny new car, the feelings they inspire happen when something inside you is triggered by a particular variation in the frequency and energy of light waves.
Those black vertical lines in Fraunhofer's spectrum? They occur when the light waves of those particular colors are being absorbed. It happens on another level of reality far smaller than the world we're used to operating in. Let's go for the hydrogen atoms. The hydrogen atom is the most plentiful kind of atom in the cosmos and the simplest. It has only one electron and only one proton. We've entered the quantum realm. In an hydrogen atom, an electron doesn't exist between orbitals. It disappears from one orbital and reappears in another. And Quantum elevators only stop at certain floors. The size of the electron orbits are strictly limited and different for the atoms of every element. That's why the elements are different. The chemistry of anything is determined by its electron orbits.The force that holds an electron in orbit has nothing to do with gravity. It's a force of electrical attraction. The electron dances a wavy ring around the central nucleus of a hydrogen atom and makes quantum leaps from orbit to orbit, up or down. The larger the orbit, the greater the energy of an electron, an electron has to get energy to leap to a larger orbit and it has to lose energy to jump back down. Every upward leap is caused by an atom absorbing a light wave but we have no idea what causes the downward leaps. What we do know that such leaps always produce a light wave whose color matches the energy difference between the orbitals. The Sun's surface radiates light waves of all colors. If you look at sunlight through a prism, you 'll see its spectrum. When you magnify the spectrum with a telescope, as Joseph Fraunhofer did,you raise the curtain on the electron dance within the atom. When the energy of the electron flags and it drops to a lower orbital, the light wave it emits scatters. Most of it doesn't reach us, that leaves a dark gap or black vertical line in the spectrum. These dark lines are the shadows cast by hydrogen atoms in the atmosphere of the Sun. Sodium atoms cast different shadows. Their electrons dance to a different tune. A grain of table salt is composed of sodium and chlorine atoms. Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.When the energy of the electron flags and it drops to a lower orbital, the light wave it emits scatters. Most of it doesn't reach us, that leaves a dark gap or black vertical line in the spectrum. These dark lines are the shadows cast by hydrogen atoms in the atmosphere of the Sun. Sodium atoms cast different shadows. Their electrons dance to a different tune. A grain of table salt is composed of sodium and chlorine atoms. Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.When the energy of the electron flags and it drops to a lower orbital, the light wave it emits scatters. Most of it doesn't reach us, that leaves a dark gap or black vertical line in the spectrum. These dark lines are the shadows cast by hydrogen atoms in the atmosphere of the Sun. Sodium atoms cast different shadows. Their electrons dance to a different tune. A grain of table salt is composed of sodium and chlorine atoms. Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.These dark lines are the shadows cast by hydrogen atoms in the atmosphere of the Sun. Sodium atoms cast different shadows. Their electrons dance to a different tune. A grain of table salt is composed of sodium and chlorine atoms. Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.These dark lines are the shadows cast by hydrogen atoms in the atmosphere of the Sun. Sodium atoms cast different shadows. Their electrons dance to a different tune. A grain of table salt is composed of sodium and chlorine atoms. Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.Ten million billion of them doing their crazy dances in a single grain of salt and a single iron atom with 26 electrons is like a great big production number in a Broadway musical. Fraunhofer's lines are the atomic signatures of the elements writ large across the cosmos.
The planets, the stars, the galaxies, we, ourselves and all of life, the same star stuff. Using spectrum, we discovered that our universe is expanding but perhaps the greatest revelation of spectroscopy is the discovery of the thing it cannot see. A hidden universe of dark matter, six times more massive than the familiar cosmos. It's made of some mysterious substance, that does not emit, reflect or absorb any king of light. We only know it's there because of its gravity with pulls on all the galaxies and speeds up the visible stars within them.
We can see mysterious explosions in distant galaxies in gamma-ray light. And in microwave light, we can see all the way back to the birth of the universe.
EP06【deeper, deeper, deeper still】
Behold the carbon atom, the essential element for life on Earth. It can bond with up to four other atoms at a time and can connect with many different kinds of atoms as well as other carbon atoms. It can curl into rings and string together into chains, building molecules far more complex than any crystal. The carbon-based we call proteins, the molecules of life contain literally hundreds of thousands of atoms. Carbon atoms are the backbone of the molecules that make every living thing on Earth, including us . That's the difference between rocks and living things. Life can make enormous molecules of stunning size and complexity, freeing matter to improvise, evolve and even love.
In everyday life on our world, on the scale of atoms, material objects never really touch. Each atom has a tiny nucleus at its center surrounded by an electron cloud of lines of force. As the atoms approach each other, the boy's electron clouds push away the girl's. More than 99.9% of the matter of any atom is concentrated in its nucleus. The nucleus is surrounded by an electron cloud which produces an invisible field of force and acts like a shock absorber. The configuration of the electron cloud determines the nature of an element. In the ordinary course of things here on Earth, the nuclei never touch. We have a sensation of touching but that's really just our invisible force fields overlapping and repelling each other.
Cosmos rays mostly protons and electrons that rain down from space cannot get through all that rock above us. But matter poses no obstacle to a neutrino. A neutrino could pass through 100 light-years of steel without even slowing down. Neutrinos hardly interact with matter at all. That's why you need so much of it to catch even one of them. On those rare occasions when a neutrino actually does collide with a particle of ordinary matter, it produces a ghostly ring-shaped flash of light. We're lying in wait for a particle that weighs next to nothing, even the minuscule electron has more than a million times its mass. When the supernova in the large Magellanic cloud blew its top in 1987, this is what it would have looked like in here. The large Magellanic cloud is in our Southern hemisphere,so the neutrinos didn't come through that half-mile of rock above us. They had to pass through the thousands of miles of rock and iron below us to reach this detector. But the coolest thing was that those neutrinos hit Earth three hours before the light from the supernova did.
Imagine that all the matter and energy of the observable universe was concentrated into something no larger than this. That's the size of the universe when it was a trillionth of a trillionth of a trillionth of a second old. All the matter and energy of the hundred billion galaxies now splayed out across the billions of light-years were once pent up in something the size of a marble. It's far too dense for any kind of light to move through it, but no obstacle for the likes of neutrinos. The big bang must have produced stupendous numbers of neutrinos which flew unhindered through that inconceivable crush of matter. The very thing that makes them almost impossible to detect is what allows neutrinos to sail through the curtain that conceals the beginning of time, where are they now? Everywhere throughout the universe.Neutrinos from cartoon are within you. From a marble to the cosmos.
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