"There are some oddities in the perspective with which we see the world. The fact that we live at the bottom of a deep gravity well, on the surface of a gas covered planet going around a nuclear fireball 90 million miles away and think this to be normal is obviously some indication of how skewed our perspective tends to be."
"I believe our future depends on how well we know this Cosmos in which we float like a mote of dust in the morning sky."
Man seems merely dust postponed: the sublime as an encounter pleasurable, intoxicating, even with human weakness in the face of strength, age and size of the universe.
Alain de Botton
- Universe grows and cools until 100 seconds after the Big Bang. The temperature is 1 billion degrees, 109 K. Electrons and positrons annihilate to make more photons, while protons and neutrons combine to make deuterons. Almost all of the deuterons combine to make helium. The final result is about 3/4 hydrogen, 1/4 helium by mass; deuteron/proton ratio 30 parts per million. There are about 2 billion photons per proton or neutron.
- One month after the Big Bang the processes that convert the radiation field to a blackbody spectrum become slower than the expansion of the Universe, so the spectrum of the Cosmic Microwave Background (CMB) preserves information back to this time.
- Matter density equals radiation density 56,000 years after the Big Bang. The temperature is 9000 K. Dark matter inhomogeneities can start to collapse.
- Protons and electrons combine to form neutral hydrogen. Universe becomes transparent. Temperature is T=3000 K, time is 380,000 years after the Big Bang. Ordinary matter can now fall into the dark matter clumps. The CMB travels freely from this time until now, so the CMB anisotropy gives a picture of the Universe at this time.
- The first stars form 100-200 million years after the Big Bang, and reionize the Universe.
- The first supernovae explode and spread carbon, nitrogen, oxygen, silicon, magnesium, iron, and so on up through uranium throughout the Universe.
- Galaxies form as many clumps of dark matter, stars and gas merge together.
- Clusters of galaxies form.
- The Solar System and Sun form 4.6 billion years ago.
- Now: The time is 13.7 Gyr after the Big Bang, and the temperature is T=2.725 K. The homogeneous patch is at least 1029 cm across, which is larger than observable Universe.
Even though the universe is now a chilly 2.725 K, it was once much hotter. In fact, from the moment of the initial big bang singularity until nearly 100,000 years later, the universe was hot enough so that electrons and protons had too much energy to come together and form neutral atoms. What existed was a "primordial soup" full of free electrons, protons and neutrons.
"Asia and Europe: tiny corners of the Cosmos. Every sea: a mere drop. Mount Athos: a lump of dirt. The present moment is the smallest point in all eternity. All is microscopic, changeable, disappearing. All things come from that faraway place, either originating directly from that governing part which is common to all, or else following from it as consequences. So even the gaping jaws of the lion, deadly poison, and all harmful things like thorns or an oozing bog are products of that awesome and noble source. Do not imagine these things to be alien to that which you revere, but turn your Reason to the source of all things."
— Marcus Aurelius
Most of the Universe is dark. The protons, neutrons and electrons that make up the stars, planets and us represent only a small fraction of the mass and energy of the Universe. The rest is dark and mysterious.
Through his spyglass, in 1609 Galileo saw that there were spots on the Sun, imperfections on the Moon, and that the Milky Way was composed of millions of faint stars. His most stunning (and controversial!) discovery was of satellites orbiting Jupiter, dashing the concept that the Earth was the center of the Universe. (NASA)
The more I learn about the universe, the less convinced I am that there's any sort of benevolent force that has anything to do with it, at all
-Neil degrasse Tyson
The Universe is Rated R for Cosmic Violence. Since the Big Bang the Universe has been a dynamic mix of exploding stars, colliding galaxies, black holes, dark matter, comets and asteroids- this cosmic violence is on such an immense scale that it makes our tiny planet seem like a distant spectator hoping not to be noticed by the war of the titans. But it will be noticed and has been in the past. There is a huge nuclear fire ball called the sun in our solar system that will become a red giant and the Andromeda galaxy heading towards our own galaxy.
"A general problem with much of Western theology in my view is that the god portrayed is too small. It is a god of a tiny world and not a god of a galaxy much less of a universe."
The gods of the human primate from this little blue planet in the universe seem to be too small, too human and too petty to be the ultimate force in this giant cosmos.
The created gods of the human mind are too small and petty for the grandeur of the stars and universe. Human gods do not even cover the scale of the earth and its history much less the universe.
"A universe in which everything is known would be static and dull, as boring as the heaven of some weak-minded theologians ."
"Ideologies separate us. Dreams and anguish bring us together."
- Eugene Ionesco
Most of the atoms in our body once existed inside a star.
The elements in our bodies, and all the other life forms on our planet, and the elements that make up the Sun and all the places in our solar system – they were all created long before we were even a dim glow in a cloud of gas and dust.
So, where did those elements come from?
Let’s start with hydrogen – it’s the most plentiful. And it’s what stars are made of. All the hydrogen in the universe was created during the Big Bang – the event that began the universe almost 14 billion years ago.
Hydrogen combines easily with other elements. When it joins with oxygen — it makes H2O – water – which we know is essential for life. In fact, WE are mostly water. Our skin, organs, muscles, bones, and nerves basically give the water a place to hang out.
The other elements in our bodies – the calcium in our bones, the iron in our blood, the carbon molecules that are the underpinnings of proteins and amino acids – those were all cooked up inside stars that died long before the solar system ever formed.
So, in a sense, we – and everything we see around us – are made up of the ashes of old, dead stars.
Science Writer Carolyn Collins Petersen - Astronomy Podcast
"...one of the strongest motives that lead men to art and science is escape from everyday life with its painful crudity and hopeless dreariness, from the fetters of one's own ever-shifting desires. A finely tempered nature longs to escape from the personal life into the world of objective perception and thought."
"A person starts to live when he can live outside himself."
"A human being is a part of a whole, called by us _universe_, a part limited in time and space. He experiences himself, his thoughts and feelings as something separated from the rest... a kind of optical delusion of his consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and to affection for a few persons nearest to us. Our task must be to free ourselves from this prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty."
"Now he has departed from this strange world a little ahead of me. That means nothing. People like us, who believe in physics, know that the distinction between past, present, and future is only a stubbornly persistent illusion."
"Imagination is more important than knowledge."
"We can't solve problems by using the same kind of thinking we used when we created them."
"Education is what remains after one has forgotten everything he learned in school."
"The important thing is not to stop questioning. Curiosity has its own reason for existing."
"We are just an advanced breed of monkeys on a minor planet of a very average star. But we can understand the Universe. That makes us something very special."
"It surprises me how disinterested we are today about things like physics, space, the universe and philosophy of our existence, our purpose, our final destination. Its a crazy world out there. Be curious."