Part 1 of this series chronicles NASA’s finest accomplishments in space exploration – the moments that inspired generations over the last 50 years. Re-discover the highlights of mankind’s progress including achievements such as the Freedom 7.
Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into helium, and eventually helium into carbon (and also some oxygen and neon). When this happens they expand, get brighter, and cool off, becoming red giants. They lose most of their mass, exposing their cores, and then cool off over many billions of years.
The only reason life on Earth is possible is because of our stable orbit around the Sun. Elsewhere in the Universe, orbits are chaotic, violent and destructive. On the largest scale, orbits are a creative force and construct the fabric of the Universe.
Europa - an icy moon of Jupiter 485 million miles away from Earth - may be our best hope for finding alien life in our solar system. Everywhere we find water on Earth, we find life. What does this mean for the search for life beyond Earth? Scientists believe that on Europa there is a liquid ocean buried beneath its icy crust. To find out if this alien ocean holds life, well need to get there, penetrate the ice shell, and navigate in an alien sea. In this episode of Explorer, well plunge headlong into the challenges of discovery on an alien world. Well meet the scientists, adventurers, and engineers who are determined to launch a mission to Europa - and follow them through the challenges, frustrations, and triumphs that come with planning a distant mission to an alien world. Through high-end CGI and quests to the edge of our planet, well go on a journey to and alien moon called Europa. To answer the basic question: Are we alone in the universe?
2010 • Astronomy
How does light escape from the sun? We take a journey from the centre of the sun, following the path of light. We witness its fiery birth from in the core, its 430,000 mile battle against gravity and magnetism, and its escape from the solar surface.