Albert Einstein’s name literally sends shivers down my spine.
This is the man who discovered physics as we know it. This is the man who filled in the gaps where even Newton’s laws of motion went wrong and expanded our understanding of the universe.
This man was a genius in every right—even if his social skills were somewhat lacking.
By the way…I can’t help but notice this is my first post with actual photographs of the scientist in question, instead of portraits. We’re moving along, people…
So. To the point. Einstein is famous for taking revolutionary and widely accepted laws of physics—those that Newton figured out—and showing where there were some holes in the math. But Einstein wasn’t just an annoying critic.
He took it all a step further…and showed us how physics really works.
He came up with the idea of relativity. Continue reading
So, the moon stays in orbit around the Earth, right?
Yeah, I thought so. But why? The moon’s orbit is not a straight line, which means it’s accelerated motion (using the physics definition, which is absolutely any change in speed or direction).
And in order for acceleration to happen, according to Newton’s first law of motion, a force has to happen—meaning, something has to reach out, touch the moon, and drag it into orbit around Earth.
Well, that doesn’t happen, last I checked. I mean, it’s not like we have some kind of giant cord connecting us to the moon. How crazy would that be?
So why does the moon orbit the Earth? Continue reading
It is surprisingly difficult to find a flattering image of Tycho Brahe.
Honestly. Do me a favor and do a Google image search for the guy. It’ll come up with all sorts of disfigured images, mostly because his nose got messed up in a sword fight…
I know what you’re thinking. A classical astronomer in a sword fight? Suddenly these people seem less like heroes of modern-day science and more like human beings with lives of their own.
Tycho certainly fits the trend. He’s known for being quite the unpopular sort. Bad-tempered and vain, there were few who respected him for more than just his astronomical accomplishments—and even those were few.
So why is he even important, then?
In my last post, I showed you just how huge astronomical distances really are. There’s a reason people say that incredible things are “astronomical!”
The image above illustrates how far Earth is from the nearest star, Proxima Centauri. But what does it mean for two objects to be 4.3 light years apart?
The light year is a unit of distance, used to measure distances that escape traditional units on Earth. It’s impossible to measure the universe in kilometers or miles; many thousands fit into one planet alone.
Even “astronomical units,” the distance between the Earth and the sun, are too small. That distance, as we saw in my last post, is barely a fraction of the distances in our solar system alone.
So what exactly is a light year?
In the 4th century B. C. E. (Before Common Era), scientists believed the Earth was the center of the universe. Before that, they were convinced the Earth was flat.
Now, if anyone so much as mentions that the Earth is the center of the universe, they are quickly corrected. The very idea is absurd. (Although there are in fact online “societies” for people who believe the Earth is flat.)
We now know that not only is the Earth not the center of the universe, but neither is the sun, which is undeniably the center of the solar system. Were we to zoom out much further and take a look at our galaxy, the Milky Way, we would find that the sun is not even near the center of its own galaxy.
In fact, it’s located in a small “spur” of stars just off one of the spiraling arms of the galaxy. Since the current theory states our universe is infinite, there can’t even be a center, and thus our galaxy is not the center of everything. How wrong those early astronomers were!
But what does all this mean? Where exactly are we in the universe?