With the help of thousands of volunteers, a team of astronomers has created the most comprehensive 3D map of so-called brown dwarfs in the vicinity of the sun to date. You have now presented the map with 525 celestial bodies, including 38 newly discovered objects. According to the research results, the closer environment of our sun is also particularly diverse compared to other areas in the Milky Way, they explain. It is the latest scientific analysis based on the “Backyard Worlds: Planet 9” project, in which amateur researchers help evaluate astronomical recordings.

Search for stars on the internet “Backyard Worlds: Planet 9” was the beginning 2017 with a special website went online. Interested parties can watch thumb-cinema-like film sequences recorded by NASA’s Wise space telescope and search for moving objects on them. Human observers can play to their strengths here, because algorithms are overwhelmed by the many image artifacts. Anyone who finds something can mark it for examination by astronomers.

The brown dwarfs sought in this project are celestial bodies that are not massive enough to ignite a nuclear fusion, as in stars, but at the same time clearly more massive than (exo-) planets. Some aren’t even as hot as boiling water and might even have clouds of water. Especially with the finds of several of these particularly cold specimens, the project is making a significant contribution to closing previous gaps. Overall, the map covers an area with a radius of 65 light years.

In the end, the researchers and their helpers ran out of time because that NASA’s Spitzer Space Telescope was shut down a year ago. Before that, it could be used again to determine the position of hundreds of the discovered brown dwarfs – as the basis for the 3D map now being presented. “Without the Citizen Scientists, we would not have been able to create such a complete compilation in such a short time,” explains Davy Kirkpatrick of the California Institute of Technology. They also found the coldest brown dwarf to date with temperatures below freezing point (of water). The scientists are now presenting the current status of their research in the specialist magazine The Astrophysical Journal Supplement, with many helpers from “Backyard Worlds: Planet 9” being listed as co-authors.

(mho)