Most children in the U.S. must endure the public education system. Teachers shovel facts into generation after generation of rambunctious children and sullen teens until they graduate. But you leave school knowing a few undeniable truths, which makes it worth the trouble, right? Actually, some of those truths are not so true.
The Planets Revolve around the Sun
Now it seems laughable that anyone ever believed that the sun revolved around the Earth. Planets revolve around the sun. But that’s not exactly accurate. Imagine a solar system model. The sun is stuck in the middle on a pillar and all the other planets can spin around it on wires. You can see this kind of model of the solar system in classrooms, libraries, and even movies.
Though, the truth of the matter is the sun is an orbiting object. It also rotates around the true center of the solar system, the barycenter. Which contains absolutely nothing.
The sun has eight planets, so the way these all orbit about the barycenter isn’t an exact circle, but rather a kind of wobbling ring.
“Zero Gravity” in Open Space
“Zero gravity” doesn’t exist. If you’re on the 130th floor of a skyscraper, gravity pulls at you the just the same as when you are on the ground level. Because if gravity disappeared just a few miles above the surface, then how does the Earth maintain gravitational influence over the moon? And how can the sun keep its grip on Pluto?
The “floating” sensation experienced by astronauts is real. But it’s not because there isn’t gravity. What they’re actually experiencing is a kind of never-ending fall.
When something is orbiting, it is actually falling in a controlled way. Something in orbit around the Earth is falling towards the ground but missing. The “zero-gravity” that astronauts feel is actually a free-fall similar to what a skydiver jumping out of a plane.
The Definition of a Desert
“Desert” seems easy to define. It’s the sandy place, one ‘s’ away from ice cream. If we say “jungle,” you picture trees. If we say “desert,” you picture sand. What’s the biggest desert in the world? The Sahara? The Mojave? The answer is Antarctica.
The actual definition of “desert” is a place that receives 15 or fewer inches of rain. Antarctica qualifies. You might think, “That’s semantics. It doesn’t rain in Antarctica, it snows.” You would still be wrong. It hardly ever snows in Antarctica. The ice has built up over millions of years, and the amount of fresh snow is so small that it’s classified as the driest continent on Earth. Further, there are parts of Antarctica that receive so little snowfall they actually look the part of “desert,” such as the Antarctic “Dry Valleys.”
The Definition of Life
NASA and foreign space agencies send robots to other planets in the hope of discovering if life exists elsewhere in the universe. Maybe before we try to discover it somewhere else we should ponder: What is life?
People, birds, magnetic super-frogs, all living things, right? Furniture, rocks, and skyscrapers are lifeless, unthinking, inanimate objects.
But there’s a “gray area” between “alive,” and “lifeless.” There is a gray area that encompasses a part of the biosphere that includes tiny things. Are viruses are alive? Viruses are distinct from bacteria, in that they don’t have cells, but they do have DNA, and they can still do damage if they get into your body.
So they’re alive, right? But viruses don’t breathe, eat, or anything else that a living organism does. If something is not alive in the first place, it can’t die. One thing it can do, and this usually defines a “living thing,” is reproduction. That only happens for viruses if they are inside a cell that’s alive.
Presently, scientists are toying with the notion that viruses may be in the “alive” category, but there is also the virus-like viroids, which are organisms that are even simpler than viruses, and mostly affect plants. And then there are prions. Prions are messed-up proteins responsible for exotic diseases like Mad Cow Disease. Are they alive? Nobody really knows! Medicine struggles with this because if prions are alive, we can’t kill them.
Some little chemical blobs have been created by scientist Martin Hanczyc that he calls “protocells,” which take in energy from the environment, move around, and grow. Are they alive?