Up Next
Back to Show
PBS Space Time
Why is the Earth Round and the Milky Way Flat?
Season 2
Episode 20
Our universe is not a very diverse place when it comes to shapes. Large celestial bodies become spheres, galaxies become discs, and there is little room for variation. Why is this? Well it turns out physics has some pretty strict rules when it comes to creating new planetary bodies.
Support Provided By
18:42
Gravitons, the particle of quantum gravity, may be impossible to detect.
25:02
2025 was the international year of quantum science, but today we examine its origins.
21:17
We’ve found lots of “habitable” worlds but we don’t know what factors are needed for life.
19:52
Antimatter drives sound like science fiction, but they may not be as far as you think.
23:22
Does quantum mechanics allow the future to retroactively influence the past or not?
19:14
Life on mars could result in humanity’s destruction via Fermi Paradox.
19:01
How to build a particle collider the size of the solar system.
12:39
One of the most important reasons we go to space is to know our own planet better.
16:18
Is there evidence for the existence of an enormous number of other universes?
18:56
It may be that our very DNA inherited its twist from the underlying handedness of reality.