Astronaut Mike Massimino reveals the mysterious secrets of Saturn and its rings; using the latest science from the Cassini mission, he explores the planet's giant icy geysers, powerful hurricanes, and moon that may be hiding extraterrestrial life.
2017 • Astronomy
Beneath Jupiter's swirling clouds lie our solar system's deepest secrets: from its violent youth, through the birth of life to the death of the sun. Now, scientists are unlocking these secrets and discovering that every living thing exists thanks to Jupiter.
Harvard professor and best-selling author, Dr. Lisa Randall, simplifies and expounds upon some of modern physics' most basic questions. What is dark matter and dark energy? What is the fundamental nature of space and time? What do we not know yet about the universe and its fundamental properties?
The expanding universe is a complicated place. During inflation the universe expanded faster than light, but that's something that actually happens all the time, it's happening right now. This doesn't violate Einstein's theory of relativity since nothing is moving through space faster than light, it's just that space itself is expanding such that far away objects are receding rapidly from each other. Common sense would dictate that objects moving away from us faster than light should be invisible, but they aren't. This is because light can travel from regions of space which are superluminal relative to us into regions that are subluminal. So our observable universe is bigger than our Hubble sphere - it's limited by the particle horizon, the distance light could travel to us since the beginning of time as we know it.