Tyson starts with water. Its molecule is pretty simple: two atoms of oxygen (O) and one of hyrdogen (H). More on atoms later. But, what makes water a liquid? Tyson illustrates how molecules have energy from the movement in their atoms, and it is this movement that creates heat. The more heat, the more molecules move. Take away heat, and molecules move less and create less heat, eventually becoming rigid and solid ice. Keep upping the heat, and molecules move so much they actually split up, and become steamy water vapor.
But let's stick with water. Specifically, dew. Tyson shrinks down Imagination so it will fit in a dew drop. I guess a smart car wasn't available. A dew drop, to the micro-organisms in it, is like an entire ocean, with bacteria and other microbes. Tyson shows some unlucky little guy fighting a paramecium, and being repulsed with every try.
Bringing flagella to a cilia fight
Tyson then gives us what must be his favorite little guy: the tardigrade, aka the water bear. By the time the first season of Cosmos is over, I expect to know by heart that: it's been around about 500 million years, and has survived five previous mass extinctions. Tardigrades can survive extreme heat and cold, live without water indefinitely, and can even survive in the vacuum of space.
Judge me by my size, do you? And well you should not.
But what is this process? Tyson awesomely calls is the molecular industrial complex. And photosynthesis is only one of its processes. Plants have a little doo-hickey(organelle) called a chloroplast, filled with the chemical chlorofill, an every leaf. It produces the green color we've come to associate with all plant life. Sunlight hitting the chloroplast starts an assembly line of chemical interactions, in which hydrogen from water molecules is combined with the CO2 the plant just inhaled. This breaks down the water molecule, produces a couple of enzymes for use as energy, and releases the oxygen from the water molecule. The plant then exhales the oxygen it doesn't want anymore.
Plant is a synonym for factory. Coincidence?
So what do plants do when the sun's down for the day? They take those enzymes storing the suns' energy, and re-combine them with more CO2 and water, producing more and more sugars to keep the plant going 24/7.
Couple of things: these molecular movements happen way too fast for human eyes to even see, producing the instant reactions of living things, and the world's living plants produce a fucking fuck load of energy. On a 24/7, totally always working solar battery. With no pollution. Could it replace fossil fuels?
Another benefit of photosynthesis is flowers. Although they don't have chloroplasts, the flower is a huge part of a plant's reproduction, or rather spread by pollen. Plants that attracted insects to spread its seeds simply spread more, starting with orchids. In fact, one specific orchid led to the discovery of a moth. Charles Darwin saw the common orchid of Madagascar, an island off the south east coast of Africa. The nectar, which insects access for their own food and get dusted with pollen to spread the plant, is at the bottom of a long 'pit'. But, how can the plant reproduce, which it did, if the nectar is so hard to reach? Darwin predicted that there was an insect that accessed this pollen with an extra long appendage. But what kind of insect could have a foot-long appendage? The Morgan's Sphinx Moth, that's what. Predicted by Charles Darwin, using the principle of natural selection, discovered in 1903.
You're welcome
Flowers do more than feed insects and spread more orchid plants. They also release gas molecules. Each molecule of a gas has a distinctive shape caused by the way the atoms bond. Your nose has receptors, that process information about gases we inhale based on the shape of the molecule. All this info is sent to the brain, which processes the information - OH MY GOD! SMOKE! RUN!
Yep, those molecules alert the brain to any possible smelly threats nearby.
Smells also trigger reactions, good or bad, pretty quickly, thanks to it's awesome location by both the hippcampus, which forms memories, and the amygdala, which governs emotional responses.
Tyson switches gears, going back in time to ancient islands in Asia Minor, where humans made huge intellectual leaps. Thales taught that events in natural had natural, non-god, non-myth explanations. Thales also invented using deductive reasoning to figure out geometric laws, and may have been a teacher of Pythagoras, bane of 10th grade geometry students everywhere. Democritus taught his disciples that all the universe were indivisible particles called atoms, and void. Void was necessary for the universe, so matter could move around. Atoms themselves came in different shapes in order for the substances they made to have their characteristics.
His atom theory was a good start. Looking at a solid, non-living thing like a rock or mineral, the atoms simply repeat again and again, in an unchanging structure, like a row of Rockettes. That's because most elements' atoms have very limited bonding capability. What if an atom could bond in any direction, with multiple bonds, that could create molecules of any shape? Meet Carbon (C).
Like a people person, but an atom
Any one carbon atom can bond with four other atoms at a time, and with just about any other atom. You can literally create any kind of shape of molecule if you've got some carbon lying around. Carbon is the most versatile of bonding atoms. Even silica stands in awe of carbon. Carbon also happens to be the building block of almost all living things, mostly because of the variety of compounds you can make with it. The source of life's variations, and therefore its evolution.
Atoms are made of protons, with a positive charge; neutrons, with no charge; and electrons, with a negative charge. Similar charges repel each other, while different charges attract. No charge mitigates the repel/attract force. Let's say I wanted to hit someone. I'd never actually make contact, although the receiver of my fury might disagree. That's because the atoms that make up my skin and my enemy's have electrons that will repel each other, so the atoms never actually touch. Why do we feel touch? Because our skin's receptors sense the energy field created when electrons are repelling each other. So, there's always a space between atoms.
In fact, in the micro-universe, there's way more void than particles. Inside an atom, the nucleus is to the rest of the atom as a dust mote is to a cathedral. Inside the nucleus, the nuclear force keeps the protons and neutrons in a tight dance around each other. The electrons circling the nucleus, far away by micro-universe standards, keep atoms from actually touching each other.
Except in the sun. Atoms are all over each other there, like an atomic orgy. The sun is ridiculously hot, which makes the atoms always gas with weak molecular bonds. The heat comes from the gravity of the sun's mass making the atoms move all the time. The more gravity (or mass), the hotter the star. The atoms are moving so fast, they literally override the electrons' protection and the nuclei combine. The gravity pulling atoms together is counteracted by the outward pressure of gases from the center. It's an almost unending tug-of-war, with a light photon actually needing 10 million fucking years to get from the center of the sun to the sun's surface. Once it's there, the photon has an easy 8-minute trip through void to Earth.
Our sun fuses hydrogen, but hotter stars also fuse helium into carbon and oxygen. When they die, they explode from the forces inside. A star's violent explosion is called a supernova. Besides emitting carbon, oxygen, iron and a wealth of elements needed to make other stars, planets and Barbie dolls, supernovas release a particle called a neutrino.
If neutrinos were a chess piece, they'd be the Queen. They can go anywhere, through anything. With a mass 1-millionth of an electron. They're produced even before the star goes supernova, getting out way ahead of the actual explosion, like rats deserting a sinking ship, so far ahead by the time the star explodes that we can detect them hours before a supernova's light reaches us. They're easy to miss, as we can't normally see them or detect them near the surface of the earth. They solved a huge problem in particle physics, when Wolfgang Pauli realized that fusing nuclei lost a bit of energy. Instead of throwing out the Law of Conservation of Energy, Pauli speculated that the energy was transferred to another, undetected particle.
The only places we can detect them, in any way, are in deep underground facilities, a good half-mile below the surface. There, rooms filled with light detectors embedded in distilled water produces flashes of light whenever a neutrino, passing through the Earth, wanders through. Neutrinos can pass through unlimited matter, so a facility will get neutrinos coming from any direction.
On the trail of the wild neutrino
Neutrinos also got out of the Big Bang early, just like they did for a supernova. Scientists are looking for a low-level background of neutrinos, similar to the microwave radiation hanging out in the universe, left over from the Big Bang. They'll be looking for a while. If those neutrinos got out ahead of the cosmic light horizon, they've gone past the wall of forever.
If the universe is that marble, Tyson is awash in our universe's early neutrinos
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