Space
Read space related news with special emphasis on NASA, cosmos, satellites and universe
What Is a Galaxy, and How Many Are There?
A galaxy is a city of stars, held together by gravity and adrift in a universe that holds hundreds of billions more like it. Ours is just one. Here is what a galaxy actually is, and how astronomers count them.
What Is the International Space Station?
For more than two decades, humans have lived without a break aboard a laboratory the size of a football field, circling the planet every 90 minutes. Here is what the International Space Station is and why it exists.
What Is a Light-Year, and How Far Is It?
Despite the word year, a light-year measures distance, not time. It is how astronomers cope with a universe so big that miles and kilometers stop making sense. Here is what it really means.
How Do the Tides Work, and Why Two a Day?
Twice a day the sea climbs up the beach and slides back down, on a schedule set by an object 384,000 kilometers away. Here is how the Moon, and a bit of the Sun, moves the whole ocean.
How Do Satellites Stay in Orbit Without Falling?
Thousands of satellites circle overhead right now, and gravity is pulling on every one of them. So why don’t they fall? The answer is stranger and simpler than it sounds.
What Is Dark Matter, and Why Can’t We See It?
Most of the matter in the universe is invisible. We cannot see it, touch it, or make it in a lab, yet without it galaxies would fly apart. Here is what dark matter is.
What Is a Black Hole, and What’s Inside One?
A black hole is a place where gravity wins so completely that even light cannot leave. Here is what they are, how they form, and the honest answer to what lies inside.
How Do Rockets Actually Reach Orbit?
Getting a rocket up to space is the easy part. The real trick, and the reason rockets are almost all fuel, is going sideways fast enough to fall around the planet forever.
Can You Hear Sound in Space?
In space, no one can hear you scream, and that tagline is basically correct. But NASA has released the ‘sound’ of a black hole, so what is actually going on?