In August 1977, the Big Ear Radio-telescope in Ohio received a strange signal from the Sagittarius constellation while searching for intelligent extra-terrestrial life. It had a duration of 72 seconds and an intensity 30 times higher than usual. Named the WAW signal (as an engineer wrote ‘WOW’ on the data as it came in!), it is still being considered as one of the best examples of having being sent by intelligent extraterrestrial life. But, nothing has revolutionised the search of extra-terrestrial intelligent life as much as the recent discovery by the Kepler Satellite, of thousands of Earth-like planets where life could be possible. Join the debate with this stunning one-hour documentary from 2015, as we ask Is Anybody Out There?
An exploration of the dramatic fate of our future descendants, the technology they'll need to survive the end of this world billions of years from now and our options for colonizing and starting again on a new planet somewhere far from Earth.
Now that we’ve finished our tour of the planets, we’re headed back to the asteroid belt. Asteroids are chunks of rock, metal, or both that were once part of smallish planets but were destroyed after collisions. Most orbit the Sun between Mars and Jupiter, but some get near the Earth. The biggest, Ceres is far smaller than the Moon but still big enough to be round and have undergone differentiation.
Prof Jim Al-Khalili tackles the biggest subject of all, the universe, through a series of critical observations and experiments that revolutionised our understanding of our world. In this second part, Professor Jim Al-Khalili carries us into the distant future to try to discover how the universe will end - with a bang or a whimper? He reveals a universe far stranger than anyone imagined and, at the frontier of our understanding, encounters a mysterious and enigmatic force that promises to change physics forever.
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.