This episode documents how gravity has an effect across the universe, and how the relatively weak force creates an orbit. We also see how a neutron star's gravity works. Finally, there is a look back at how research on gravity has enabled us to better understand the cosmos.
On a bright, cold morning on 15th February 2013, a meteorite ripped across the skies above the Ural mountains in Russia, distintegrating into three pieces and exploding with the force of 20 Hiroshimas. It was a stark reminder that the Earth's journey through space is fraught with danger. A day later, another much larger 143,000 tonne asteroid passed within just 17,000 miles of the Earth. Presented by Professor Iain Stewart, this film explores what meteorites and asteroids are, where they come from, the danger they pose and the role they have played in Earth's history.
How and when will the Universe end? Gravity and dark matter are poised to annihilate the Universe in a big crunch. Expansion and dark energy may tear it apart. Or, a phase transition could kill us tomorrow in a cosmic death bubble.
It’s a golden age for planet hunters: NASA's Kepler mission has identified more than 3,500 potential planets orbiting stars beyond our Sun. Some of them, like a planet called Kepler-22b, might even be able to harbor life. How did we come upon this distant planet? Combining startling animation with input from expert astrophysicists and astrobiologists, “Alien Planets Revealed” takes viewers on a journey along with the Kepler telescope. How does the telescope look for planets? How many of these planets are like our Earth? Will any of these planets be suitable for life as we know it? Bringing the creative power of veteran animators together with the latest discoveries in planet-hunting, “Alien Planets Revealed” shows the successes of the Kepler mission, taking us to planets beyond our solar system and providing a glimpse of creatures we might one day encounter.
Second Genesis follows planetary scientist Carolyn Porco as she explores what it takes to look for life beyond Earth, and what conditions are required for life to exist. Porco makes the case that Saturn’s moon Enceladus—with its plumes of water vapor spewing into space, confirmed organic materials, and evidence of hydrothermal vents at the bottom of its liquid ocean—is the most promising place to look. Could Enceladus be the key to proving once and for all that life is not unique to Earth? And what it would mean—both scientifically, and spiritually—if we found evidence of a true second genesis right here in our own galactic back yard?
2017 • Astronomy