TALK NOT AVAILABLE 2016

Over the last decade, scientists have started to catalogue dozens of planets orbiting stars like our own Sun. These "extra-solar systems" can be very different from our own "solar system". Imagine planets as big as Jupiter orbiting a star every 12 days instead of every 12 years, or alternatively zooming close in and far away from a star, instead of orbiting sedately in a circle. But our own solar system is exciting too. When it was younger, collisions between planets were rather common. For example, the Moon formed when the Earth collided with something as big as Mars, and Mercury, Venus and Uranus all show evidence of huge collisions in the past. Not to mention that Neptune's moon, Triton, is slowly spiraling closer to the planet and in 250 million years will be torn apart, giving Neptune rings to rival Saturn's. There is a lot we have learned about planets, and a lot we have still to learn!