“No matter how exalted we think ourselves, all that we can know and become has a material basis obedient to the decipherable laws of physics and chemistry.
“And no matter how intellectually far above the remainder of life we lift ourselves, and however technically proficient we become, we will stay a biological species, biological in origin, and thence adapted in mind and body to the living world that cradled us.”
Edward O. Wilson, 1998 Phi Beta Kappa Oration – Harvard University
WHAT MAKES LIFE HEALTHY?
- What makes life healthy?
- What sustains life?
- What in life is “sacred”?
Most people associate the word “sacred” with religion.
Sacred also has a nonreligious meaning that is grounded in reality and goes to the essence of life itself.
The nonreligious meaning of sacred is that in life which – at our peril – we cannot violate, damage, dishonor, or destroy.
There is a phenomenon that I refer to as the way of life, which is in complete alignment with the nonreligious understanding of sacred.
- If we honor the way of life, we prosper.
- If we violate it, we suffer needlessly.
To explore, discover, and understand the way of life requires context, perspective, and time frames.
Many people have ideas and opinions about one thing or another but lack these essential elements.
For context, perspective, and time frames, let’s turn to three areas.
- First, we will take a look at cosmology (two blogs), the origin and structure of the universe.
- Second, we turn to evolutionary biology (after cosmology). How long has this planet and life been here? How long have we been here? What has life been through to get this far?
- Third, we look at the world of religion (following evolutionary biology blog). From where have all these religions come and why?
Danish philosopher and theologian Soren Kierkegaard observed that “Searching for truth (which is what we are after) is like searching in a pitch-dark room for a black cat that isn’t there.”
Truth is elusive.
- But truth and elements of truth are discoverable.
- Truth is stubborn, tough, and patient.
- As has often been said, facts are stubborn things.
- Chief Justice Oliver Wendell Holmes observed that “Truth is tough. It will not break, like a bubble, at a touch; you may kick it around all day like a football, and it will be round and full at evening.”
COSMOLOGY
This blog will give you a sense of our place in the universe.
You will find that we are one of countless life forms that live on a very tiny speck of a planet.
From cosmology, we know that each hour we travel in excess of a billion miles!
How do we do that?
It is as though we live on a spacecraft within a spacecraft within another spacecraft, at least.
The first spacecraft is planet Earth. We are passengers as it orbits a star that we call the Sun at a speed of 65,000 miles an hour.
Our solar system is the second spacecraft. We are passengers within it as it orbits our galaxy, the Milky Way, at 600,000 miles per hour.
The Milky Way, our third spacecraft is travelling outward among other galaxies with the expansion of the universe at speeds in excess of a billion miles per hour.
We may be, as numerous physicists and scientists believe, on a fourth spacecraft, our universe, as it travels among other universes in a multiverse.
Our planet, Earth, is tiny, just 7,926 miles in diameter and 24,000 miles in circumference.
In volume, it is only 3 millionths the size of the Sun.
We exist in a solar system comprised of the Sun, eight planets, an asteroid belt (between Mars and Jupiter), the Kuiper Belt (a donut-shaped band of frozen methane, ammonia, and water beyond the Neptune orbit), and 215 moons (Mercury and Venus: none, Earth: 1, Mars: 2, Jupiter: 79, Saturn: 82, Uranus: 27, Neptune: 14, and in the Kuiper Belt: Pluto – smaller than our moon – with 5 moons and other dwarf planets with 5 moons). More moons are discovered from time to time.
Of the eight planets, four are known as the inner (closer to the sun) and terrestrial planets: Mercury (3,029 miles diameter), Venus (7,519 miles diameter), Earth (7,926 miles diameter), and Mars (4,223 miles diameter). We exist on the third planet from the Sun, in a very narrow band in our solar system that allows life to exist at all.
The outer planets, that represent 99 percent of the mass of all the planets, are Jupiter (89,000 miles diameter), Saturn (75,000 miles diameter), Uranus (32,000 miles diameter), and Neptune (31,000 miles diameter).
Jupiter and Saturn are known as the gas giants. They are comprised mostly of hydrogen and helium gases with relatively small rocky cores. Uranus and Neptune are known as the ice giants as they are comprised mostly of frozen methane, ammonia, and water.
The Sun, in comparison to all the other bodies, is so large (865,000 miles diameter) that it comprises 99.85% of the total mass of our solar system.
As our planet orbits the Sun at 65,000 miles per hour, simultaneously, it rotates on its axis at 1,000 miles an hour.
To rotate fully, it takes what we call a day.
As we orbit the Sun, our moon, 238,857 miles away, orbits us every 27 days, 7 hours, and 43 minutes.
Earth is about 93 million miles from the Sun.
The closest planet to the Sun, Mercury, a very hot planet, is 36 million miles from the sun.
Venus, 67.2 million miles from the sun, is hotter than Mercury.
The reason is that Venus has a very thick heat-trapping atmosphere whereas Mercury, with no atmosphere, radiates its heat back out to space.
The furthest planets from the sun are the dwarf planets in the Kuiper Belt beyond the Neptune orbit. Dwarf planet Pluto, in the Kuiper Belt, is about 3,666,000,000 miles from the Sun.
The circuit that Earth orbits around the Sun is 600 million miles.
To orbit once, it takes what we call a year.
While all this is going on, our solar system orbits the Milky Way galaxy.
The Milky Way name comes from its appearance as a dim “milky” glowing band arching across the night sky, in which the naked eye cannot distinguish individual stars.
Consider our solar system: The Sun (comprised of exploding gases: 75% hydrogen, 24% helium, and 1% other gases) and its eight planets (four solid and four comprised mostly of gas), 215 moons, millions of asteroids, meteoroids, comets, and the objects in the Kuiper Belt, all orbit the Milky Way galaxy at 600,000 miles per hour like a huge self-contained space station more than seven billion miles in diameter.
How long does it take for our solar system to orbit the Milky Way galaxy one time?
Recall that it takes Earth a year to orbit the Sun at 65,000 miles an hour.
In contrast, our solar system orbits the galaxy at 600,000 miles per hour.
But even at that speed it takes 225 million years for our solar system to orbit the Milky Way galaxy one time.
All of this begs the question, “How big is the Milky Galaxy?”
To begin with, the Milky Way Galaxy contains 200-400 billion solar systems (ours is one of them).
The nearest solar system to us is Proxima Centauri.
It is one of a three-star system that includes Alpha and Beta Centauri, which tumble over each other while Proxima Centauri orbits them.
To reach Proxima Centauri from our solar system, traveling at the speed of light, 186,000 miles per second—a speed at which we could fly around Earth more than seven times in one second—would take four years and three months.
However, mass cannot travel at the speed of light. To reach Proxima Centauri, using current space technologies, would take about 6,300 years.
That’s just to reach the nearest solar system of approximately 200-400 billion in our galaxy!
Just how big is the Milky Way Galaxy?
The Milky Way Galaxy is 100,000 light-years wide.
What’s a light year? A year is typically a measure of time, not distance.
A light-year, however, is the distance covered in a year traveling at the speed of light, 186,000 miles per second, for the entire year.
A light year is equivalent to about 5,880 billion miles, nearly six trillion miles.
Multiply that times 100,000 and you have the distance across Milky Way Galaxy.
Another way to think about the size of the Milky Way galaxy is to imagine that we are going to hike from one end to the other.
We would have to hike at 186,000 per second for every second of every minute of every hour of every day of every week of every month of every year for 100,000 years.
The Milky Way Galaxy is huge.
As recently as the 1920s, we thought the Milky Way galaxy was the entire universe.
That was an error equivalent to thinking that Earth is flat.
We now know that the Milky Way galaxy is one of about 225 billion galaxies in the “observable universe.”
TO CONTINUE, GO TO BLOG “COSMOLOGY 2 OF 2”