How do astronomers make sense out of the vastness of space? How do they study things so far away? Today Phil talks about distances, going back to early astronomy. Ancient Greeks were able to find the size of the Earth, and from that the distance to and the sizes of the Moon and Sun. Once the Earth/Sun distance was found, parallax was used to find the distance to nearby stars, and that was bootstrapped using brightness to determine the distances to much farther stars.
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.
The Sun created our Solar System and in a fit of cosmic cannibalism will engulf and destroy it. However, our Solar System will see many changes before the light of our star goes out. So, what will be happening with the planets over the next four billion years, before the Sun swallows us and them?
Professor Brian Cox explores the powerhouse of them all, the sun. In India he witnesses a total solar eclipse and in Norway, he watches the battle between the sun's wind and Earth, as the night sky glows with the northern lights. Beyond earth, the solar wind continues, creating dazzling aurora on other planets.
Today Phil follows up last week’s look at the death of low mass stars with what comes next: a white dwarf. White dwarfs are incredibly hot and dense objects roughly the size of Earth. They also can form planetary nebulae: huge, intricately detailed objects created when the wind blown from the dying stars is lit up by the central white dwarf. They only last a few millennia. The Sun probably won’t form one, but higher mass stars do.