gravity
What’s This Ridge on Iapetus?
The strangest feature on Iapetus is the equatorial ridge. What could possibly create a feature like this? To paraphrase the…
How Could We Destroy the Moon?
What would it take to destroy our moon, and eliminate the enemy of stellar astronomy for all time? In the…
How Fast is Gravity?
How long would it take for the gravitational well created by the Sun to disappear, and the Earth and the…
Who Was Nicolaus Copernicus?
Polish astronomer Nicolaus Copernicus revolutionized astronomy by proposing that the Earth and other planets revolved around the Sun
How Can Black Holes Shine?
We hear that black holes absorb all the light that falls into them. And yet, we hear of black holes…
How Do We Know Dark Matter Exists?
Dark matter can't be seen or detected by any of our instruments, so how do we know it really exists?…
Could There Be Another Planet Behind the Sun?
If you've read your share of sci-fi, and I know you have, you've read stories about another Earth-sized planet orbiting…
Are Astronauts Really Weightless?
Look at those astronauts, flying through space without a care in the world. But how can they be floating when…
Don’t Look At Black Holes Too Closely, They Might Disappear
We've come a long way in 13.8 billion years; but despite our impressively extensive understanding of the Universe, there are still…
What is Gravitational Lensing?
Gravity's a funny thing. Not only does it tug away at you, me, planets, moons and stars, but it can…