Stephen Hawkings Favorite Places 2 • 2018

5:45

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.

Veritasium • 2014 • Astronomy

44:06

To determine the true age of the Earth, geochemist Clair Patterson developed the uranium-lead dating method to make an unprecedented discovery - calculating Earth's age of 4.5 billion years. But Patterson's groundbreaking discoveries were just beginning. Patterson made it his mission to draw public attention to the detrimental effects of lead in the environment and dedicated his career to fighting against the petroleum and chemical industry, eventually achieving public health's biggest victory of the 20th century.

S1E7 • Cosmos: A Spacetime Odyssey • 2014 • Astronomy

42:29

New evidence is rewriting the history of our solar system, and using the latest discoveries and cutting-edge tech, experts are investigating if our cosmic neighborhood once featured oversized alien Earths and a second Sun.

Space's Deepest Secrets • 2019 • Astronomy

2:15

"It is beyond our powers to predict the future"

4/10 • The Sagan Series • 1989 • Astronomy

6:30

The Known Universe takes viewers from the Himalayas through our atmosphere and the inky black of space to the afterglow of the Big Bang. Every star, planet, and quasar seen in the film is possible because of the world's most complete four-dimensional map of the universe, the Digital Universe Atlas that is maintained and updated by astrophysicists at the American Museum of Natural History.

Astronomy

10:31

An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer.

#5 • Crash Course Astronomy • Astronomy