What Causes the Lunar Phases?


We see it almost every night of our lives. For thousands of years, the greatest philosophers and astronomers alike have watched its face change and wondered why.

Step outside and observe the moon every day for a month and you will notice something fascinating. Over the course of the entire month, the moon will go through an entire cycle of phases—no more, no less.

But why?

The phases of the moon are something I’ve talked about before, but I wanted to spend some time on a few common misconceptions this time around and show you the truth behind the lunar phases. Continue reading

Einstein: Special Relativity


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

Moving with the Tides


Have you ever been to the beach?

If you’re from California like me, then I’m betting you have. If you’re from a place that’s not near an ocean and you’ve never been near the water all your life, then I’ll tell you a little bit about the tides.

They happen every day, twice a day. If you find yourself a nice comfortable spot overlooking the beach, you can see the waves come into the shore and then gently roll out again. If you stay for hours on end, you’ll see the water level eventually rise a bit.

And if you stay even longer, you’ll see the water level lower back down. When it’s high, it’s called high tide, and when it’s low, it’s called low tide.

The tides are partially responsible for the myth that the moon’s gravity affects you in some kind of metaphysical way. But this isn’t true at all.

So why do the tides happen? Continue reading

Newton and Gravity

earth and moon.jpg

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

The Ecliptic


The ecliptic, as astronomers call it, is the apparent path of the sun against the background of the stars in the sky.

It’s useful because it tells us how to find the planets in the sky. They can be hard to spot if you don’t know where to look, but they will always be somewhere along one imaginary line that arcs across the sky—the ecliptic.

This pattern never changes. The planets don’t follow the ecliptic exactly, but it’s useful for getting an idea of where they should be.

But why does it work—and what exactly does it mean, when it’s obvious we can’t see the sun among the stars of the night sky? Continue reading

Where Are We?


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?

Continue reading