Ptolemy – Roman astronomy – history of science
A copy of Ptolemy's map of the world Ptolemy was born in Egypt in about 90 AD, when the Romans were ruling Egypt. He was a Roman citizen. Probably he was the son or grandson of [...]
A copy of Ptolemy's map of the world Ptolemy was born in Egypt in about 90 AD, when the Romans were ruling Egypt. He was a Roman citizen. Probably he was the son or grandson of [...]
Earth's atmosphere: Did the Earth look like this right after it cooled down? What is the atmosphere? The atmosphere is the air that is wrapped all around a planet. Read more [...]
Uranus, the second to last planet out from the Sun Uranus is between Saturn and Neptune, so it's the next to the last planet away from our Sun. It takes Uranus 84 years to [...]
What are planets? The planet Venus from space Before there were planets For several hundred million years after the Big Bang, there were no planets, only stars. Planets couldn't form until the [...]
Neptune from space Neptune is the farthest planet from our Sun. Neptune is the only planet that is so far away that you can't see it without a telescope. Neptune (NEPP-toon) is [...]
Jupiter from space Jupiter (named after the Roman god Jupiter) is the next planet further out from our Sun after Mars. But Jupiter is much, much further away from the Sun than Mars is. If [...]
Lyrid meteor shower - Space Most of the universe is just emptiness - there is nothing there at all. It's dark. That's space. But within the space there is a [...]
What is gravity? The Moon orbiting Earth (taken from space) - NASA What does gravity do? Gravity attracts all objects towards each other. Gravity has been around since the very [...]
Seeing the planet Mars - a Mars project See Mars for yourself! You can see Mars for yourself in the sky at night, without a telescope or binoculars. Look for [...]
Pedaling will make her accelerate. So will going downhill. Acceleration is a way to measure how fast something is speeding up. Suppose you are riding your bike. You start out [...]