Now that gravitational waves are definitely a thing, it’s time to think about some of the crazy things we can figure out with them. In some cases we’re going to need a gravitational wave observatory - in fact, we've already built one.
Black holes! From Stephen Hawking to Interstellar, black holes are mammoths in the world of science AND sci-fi. But what exactly IS a black hole? Do events happen inside black holes? Are black holes really a hole? Are black holes really black?! Join Gabe on this week’s episode of PBS Space Time as he debunks popular black hole misconceptions, and rethinks what the term, ‘black hole’, even means. Thought you knew what a black hole was? Think again!
2015 • Astronomy
Finding alien life on a distant planet would be amazing news - or would it? If we are not the only intelligent life in the universe, this probably means our days are numbered and doom is certain.
Carl Sagan teaches students in a classroom in his childhood home in Brooklyn, New York, which leads into a history of the different mythologies about stars and the gradual revelation of their true nature. In ancient Greece, some philosophers (Aristarchus of Samos, Thales of Miletus, Anaximander, Theodorus of Samos, Empedocles, Democritus) freely pursue scientific knowledge, while others (Plato, Aristotle, and the Pythagoreans) advocate slavery and epistemic secrecy.
The first part, Everything, sees Professor Al-Khalili set out to discover what the universe might actually look like. The journey takes him from the distant past to the boundaries of the known universe. Along the way he charts the remarkable stories of the men and women who discovered the truth about the cosmos and investigates how our understanding of space has been shaped by both mathematics and astronomy.
The Earth is an amazing place. It provides everything needed to sustain billions of creatures, plants and human civilization. We owe our very existence today to the planet's turbulent past. Our world was formed by a series of cataclysms, from the most powerful blast in the Universe to a planetary collision that could have destroyed it. Yet without these events, the Earth would not exist. Nor we. Could the same extraordinary chain of events have created other earth-like planets elsewhere in the Universe? Inhabited by creatures like us? The odds seem slim. But the incredible story of the birth of our world reveals that earths must be abundant. The question is no longer "are we alone" but "how far away are our neighbors?"