reviewed by Ann-Kathrin Brauer<\/p>\n\n\n\n
In addition to better-known space telescopes such as the Hubble or the James Webb Telescope, the Gaia Space Telescope has been mapping the Milky Way since December 2013. The goal of the mission is to answer questions about the origin and evolution of the stars in our Milky Way. In the interactive visualization Gaia\u2019s Stellar Family Portrait<\/a> the European Space Agency (ESA) presents the results of the mission. We have chosen this special “family portrait” as our visualization of the month March.<\/p>\n\n\n\n By scrolling independently, users are able to let the visualization take effect at their own pace. At the beginning, it is not clearly recognizable what is actually visualized here. All that can be seen is a black patch on a white background. Only when scrolling red info areas appear, which clarify what it is about: roughly 39.5 million stars. Gradually it becomes clear that the black patch we saw at the beginning is only a section, a tiny little part of the Milky Way. Slowly, the black and white image then colors up: hot stars are blue, cold stars are red. And now the visualization also becomes interactive. To bring order to the abundance of stars, 47 so-called clusters are selected. Users can click and explore them.<\/p>\n\n\n\n Further scrolling finally brings more order into the chaos. The 20,000 stars displayed are sorted horizontally according to their color: To the left are the blue hot stars, to the right the red cold ones. This is followed by a further sorting on a vertical axis according to their brightness: particularly bright stars at the top, fainter stars at the bottom. The result is the Hertzsprung-Russel diagram, “the most famous diagram in astrophysics”, John D. Barrow “Cosmic Imagery: Key Images in the History of Science”, 2008).<\/p>\n\n\n\nWhat happens in the visualization?<\/h3>\n\n\n\n