We’ve made some incredible space discoveries in the last few years, like gravitational waves and liquid water on Mars.
But considering we’ve explored only a teeny-tiny corner of the universe, there’s a lot of big questions we don’t have answers for yet.
Here are some of the biggest unsolved mysteries about space.
1. What we can see makes up only 5% of the universe
Everything we can see makes up a piddling 5% of the universe. The other 95% is part dark energy and part dark matter.
If we can’t actually see dark matter or dark energy, how do we know they’re real? The bottom line is, we don’t. Scientists think dark energyis the mysterious force that’s causing the universe’s rate of expansion to continue accelerating. However, dark energy could also be explained as just a big error in theory of gravity.
Dark matter is an invisible material that makes up the bulk of the matter in galaxies. Scientists think it exists because the gravitational force of galaxies is far too large to be explained by only the matter we can see.