PBS Space Time Season 2018 Episode 17 How Gaia Changed Astronomy Forever

PBS Space Time season 2018 episode 17, titled "How Gaia Changed Astronomy Forever," explores the revolutionary impact of the Gaia mission on our understanding of the universe. The episode begins by introducing the Gaia spacecraft and its mission to create a 3D map of the Milky Way galaxy, which would enable astronomers to study its structure and evolution in unprecedented detail.

The episode then delves into the history of astronomy and the challenges that astronomers have faced in understanding the Milky Way. Prior to Gaia, astronomers had to rely on indirect methods such as measuring the motions of stars and gas clouds to study the Milky Way. This made it difficult to obtain an accurate understanding of the galaxy's structure and properties.

The episode then explains how the Gaia mission has changed this. Gaia uses a technique called astrometry to measure the precise positions, movements, and distances of over a billion stars in the Milky Way. This data has allowed astronomers to create a detailed 3D map of the galaxy, revealing its structure and showing how it has evolved over time.

The episode also explores some of the surprising discoveries that have been made using Gaia data. For example, Gaia has revealed that our solar system is actually moving faster than previously thought, and that the Milky Way is cannibalizing other galaxies at a much faster rate than previously believed.

The episode also touches on the impact of Gaia on other areas of astronomy, such as the search for exoplanets and the study of dark matter. Gaia's precise measurements of star positions have allowed astronomers to detect the subtle gravitational tugs of planets orbiting stars, and even to detect planets indirectly through their effects on star motions.

Overall, PBS Space Time season 2018 episode 17 provides a fascinating look at the Gaia mission and its revolutionary impact on our understanding of the universe. By creating a detailed 3D map of the Milky Way, Gaia has opened up new avenues of research and made it possible to ask and answer questions about our galaxy that were previously impossible to address.