Tag Archives: Milky Way


Guide to our Galaxy

Take a virtual journey through the Milky Way! This virtual journey shows the different components that make up our home galaxy, the Milky Way, which contains about a hundred billion stars. It starts at the black hole at the centre of the Milky Way and with the stars that orbit around it, before zooming out through the central Galactic Bulge, which hosts about ten billion stars. The journey continues through a younger population of stars in the stellar disc, home to most of the Milky Way’s stars, and which is embedded in a slightly larger gaseous disc. Stars in the disc are arranged in a spiral arm pattern and orbit the centre...

Stories of the stars

Gaia, the billion star surveyor. This is the mission slogan. A billion stars. One thousand million stars… That is a lot. Really a lot of stars. If the final catalogue with just the summary of all data accumulated by Gaia were printed and all volumes were nicely aligned in my bookshelf, the row of 53,542 volumes would extend 1.3 km (and this would only be the summary data of all non-special stars). So, I hope you appreciate the point that a billion stars is really a lot. This is also what one of the space enthusiasts that visited the open day of the European Space Research and Technology Centre (ESTEC) a few...

Gaia – Surveying a billion stars

Welcome to ESA’s Gaia blog! Gaia is a global space astrometry mission. It will make the largest, most precise three-dimensional map of our Galaxy by surveying more than a thousand million stars. In this blog we’ll cover the activities from Kourou from once the spacecraft has left the clean room in Toulouse until launch. And we’ll include guest blogs from outside of Kourou – to give you an idea of the other things that are happening in the wider Gaia community. Details shortly…Watch this space!