Imagine how an object orbits. Think off throwing a baseball. Throw it hard, and it arcs to the ground. Throw it even harder, and it … Read More

Light will show you things (but so too will the dark). You can learn much about the universe from the night sky. Each galaxy and … Read More

When you point your telescope to some distant galaxy, what you see isn’t what it is; it’s what it was. And that difference, between when … Read More

Maybe you picture the universe like a stage with stars and planets sitting still while you travel about among them. Instead, idea of expansion revealed … Read More

The beauty of Hubble’s idea, which was surprisingly elegant, was this: The more distant a galaxy is, the further away it moves; and all those … Read More

That’s where Redshift comes in. It is sort of like Doppler shift, except instead of moving closer or farther from an object, we’re stretching out … Read More

The night sky looks black, with one big blotch of red in it. And the red looks familiar. It’s like the red of a ripe … Read More

But stars are not candles. In fact, they’re exactly opposite. A candle is made from burning it’s own waxy substance. As it gives off light, … Read More

The first thing most people notice when they look at a star is its brightness. But we all know appearances can be deceiving. A massive … Read More

Nope! Stars aren’t measured like lengths using a ruler. And besides, most star are so small (relative to what we see in the sky) and … Read More