The Universe: one big family

This is the story of the universe, according to science:

1) The Beginning: 14 billion years ago, everything in the universe was contained in a single infinitesimally small point. This point, smaller than an atom, had an infinite density and contained all the matter, space, and time of the universe. The point began to rapidly expand, and as the volume of the universe increased, the heat decreased, and atoms were able to form. The first atoms consisted of mostly hydrogen and helium, since these are the lightest, simplest elements. Through the force of gravity, these atoms began to accrete and accumulate in progressively larger and larger clumps.

2) Creation of Elements: Especially large clumps would be stars, which would get so massive that the matter on the inside of them experienced insanely high pressure from gravity. This pressure produced incredible heat, so much heat that the hydrogen and helium atoms were moving fast enough to overcome their repulsion to one another, and began to crash into each other and fuse. Bigger, heavier atoms began to form. Stars that were very high in mass were able to heat their cores enough to create every element up to iron (fusing iron takes more energy than it gives out), and if one of these stars died in a supernova explosion, the massive heat of the explosion was able to create even heavier elements than iron. The dusty, gassy remains of these dead stars were the building material for new solar systems. Our sun and planets formed through the same gravitational accretion process, and each had on it many elements, including those of life: hydrogen, carbon, nitrogen, and oxygen.

3) Life Stirs: After our planet cooled and formed its huge bodies of water, organic molecules began to form naturally form. There are a few different ideas on how life first began, and none are confirmed, but the following is the most plausible. The first life forms could not have been anything like a cell today; modern cells are far too complex. The first life may have been a single self-replicating molecule, a predecessor to RNA. In the water, there were organic molecules which had one end that was repelled from water and one that was attracted. This led to naturally forming spheres. If self-replicating molecule got caught up in on of these spheres, it would be protected and had a better chance to reproduce. These were the first cells: a self-replicating molecule surrounded by a layer of other molecules.

4) Adaption and Complexity: Single-celled organisms ruled Earth for billions of years. The most dominant form during this time was cyanobacteria, or blue-green algae. These algae are responsible for putting a significant amount of oxygen on the planet, and the presence of oxygen caused a diversification of life. Some cells could now metabolize oxygen, which was more energy-packed. The first multicellular life was colonial, then some cells in the colonies began specializing in one thing. These were the first organs. To talk of our own evolution in detail would be too lengthy, but it had operated on the same naturally selecting powers as the unicellular life before it. The tree of life (for humans) goes as follows:

Bacteria --> Colonial multicellular --> Polyps --> Fish --> Amphibians --> Reptiles --> Mammals --> Tree-dwellers --> Early hominids --> Humans

5) Our Place: According to science so far, life on Earth is literally one big family. All life today are very distantly related cousins; we are all offspring of previous organisms. However, life itself is made of atoms created in the cores of high-mass stars. So the cosmos, while not alive, are by definition our family, because they gave rise to life. Despite any overtones of silly new-age mysticism, the universe is literally all one. We are part of the universe, not merely observers.

- Evan

Some mind-blowing astronomical facts!

1) A neutron star is a leftover core from a dead star, composed almost entirely of neutrons. They have masses up to twice that of our sun, but can be about 15 miles in diameter (1/60,000 of our sun). Their density is equivalent to compressing the entire human race into a sugar cube.

2) In the presence of two colliding black holes, spacetime is incredibly stretched and contorted. There exists a specific looping path that you can take around the two objects that puts you in the past of where you began.

3) All the elements in the universe heavier than helium and up to iron were created in the fusion process in the cores of high-mass stars. All the elements heavier than iron were formed upon the ultra-powerful supernova deaths of these stars. These stellar explosions threw the star’s enriched guts across the universe to make the next generation of solar systems like ours. The very atoms that make up your body were created in the cores of stars. As Carl Sagan once said, “we are stardust.”

4) When solar flares are released from our sun, they not only shoot outwards but also snap back, like a breaking rubber band. Sometimes a super-powerful flare’s recoil can cause a phenomenon called a sunquake. The energy of the recoil is equivalent to covering the entire landmass of the Earth with dynamite a yard thick, and setting it off all at once. Circular ripples form on the sun’s surface move outward from the point of impact, like a pebble in a pond. Except that these "ripples" are two miles high, and travel at 250,000 miles per hour.

5) A pulsar is a highly magnetized, spinning neutron star that emits light beams caused by electromagnetic radiation from its two poles. When the poles point towards Earth, we see a pulsating effect, similar to how a lighthouse works. Because their high mass gives them so much momentum, the regularity of pulsation is as precise as an atomic clock. The fastest spinning pulsar ever discovered rotates at 600 times per second, its surface moving at about 18,641 miles per second (10% the speed of light).

6) Quasars are compact regions in the centers of massive galaxies surrounding their supermassive black holes. The energy of material falling into the black hole emits directionalized beams out of its poles. Quasars are ten trillion times brighter than our sun. If you were to count to just one trillion at one number per second, it would take you 31,546 years.

7) Magnetars are neutron stars with magnetic fields so immensely strong that they can kill a person from 600 miles away by warping the atoms of their flesh. Their magnetic fields are one quadrillion (a million billion) times that of Earth’s. On December 27, 2004, a magnetar produced the brightest event from outside our solar system in the history of astronomy. More on this event here.

- Evan

The Universe: a double-edged sword

We live in a beautiful and mysterious place. On Earth, our skies are a calming shade of blue, our clouds are fluffy and white, and our atmosphere burns up incoming meteorites and filters out dangerous radiation. Our plant life is green and vibrant, and provides our planet with vital oxygen that it would not otherwise have. Our animals are intriguing, beautiful, and extremely varied, each occupying a niche of its environment and serving a purpose in the food chain, a food chain that gives life on Earth autonomy. We are at an ideal distance from our sun, and our own moon stabilizes Earth’s climate, which is among the reasons why terrestrial life has flourished here. Even the planet Jupiter, with its massive gravitational influence, acts like shield for life on Earth, deflecting countless rogue comets and asteroids.

It seems as if everything here is perfect. Everything is fine-tuned, and it all promotes our existence. How could this place not have been made for us? The answer comes from simply looking at what we have in context with the forces of the Earth and the cosmos that would have us dead. For brevity, I have included only a fraction of these:

The Cosmos:
1) 65 million years ago, an asteroid unsympathetically struck our planet, and wiped out all but a few tendrils of the tree of life. The universe does not care that we are alive; we are participants in it, and are susceptible to its destructive forces.
2) Gamma-ray bursts are the most violent explosions in the universe. They most often occur in other galaxies, but are so powerful that they are visible to the naked eye from 10 billion lightyears away (the other side of the universe!). They are highly directional and very rare, but if one were to strike Earth, every point on the planet would experience something similar to standing a mile away from an atomic bomb.
3) In 5 billion years, our sun will turn into a red giant, engulfing our planet.
4) The Milky Way galaxy is on a one-way collision course with the Andromeda galaxy.
5) The laws of nature are NOT perfect for life. 99.9999% of the volume of the known universe will kill life instantly (heat, radiation, cold).

The Earth:
1) Earthquakes, floods, tsunamis, volcanos, hurricanes, lightning strikes, attacks from other life forms (including deadly plants and animals, infections, and other humans).
2) 99% of all life that has ever lived on Earth is now extinct.
3) We can’t live on 2/3 of the Earth’s surface, we could freeze or starve on half of what remains.

I am thankful to be alive and to live on Earth. But when I look at all the events of Earth and the universe (not just the good ones), I see that this place is in no way perfectly tuned for our existence.

- Evan