Not all astronomers do their research by saying, “And now I shall point a telescope at this object I love and learn new things about it.” The reality is that most of us sit at our keyboard, study the structure of catalogs of data already acquired, and write commands to pull potentially interesting science out of that existing data. In some cases, people can combine catalogs in creative ways to find things that no one data set can show on its own, and with follow-up observations say, “Hey – look! Something new.”

This kind of data repurposing led to the latest discovery of four new brown dwarf stars. These tiny masses are just big enough to briefly undergo nuclear reactions of heavy hydrogen, like tritium and deuterium, but they lack the needed mass to support prolonged regular hydrogen burning. Because they are small and dark, finding them is a challenge, but researchers performing the COPAINS pilot survey found a trick to success. 

They looked for stars that were cataloged as having different motions across the sky by different catalogs. They rightly figured these objects might be in binary systems, and the varying motions were seen because the stars are both moving due to their orbit in the galaxy and their orbit around a companion. All these brown dwarfs were found orbiting young stars with Sun-like masses.

All told, after looking at 25 stars, they had found ten companion objects, including these four brown dwarfs, and the team notes: The high detection rate obtained here strongly validates the use of such approaches in survey designs.

So when different catalogs don’t match, don’t ask, “What went wrong?” Ask “what science is waiting to be done?”

More Information

European astronomers discover four new brown dwarfs (Phys.org)

“Results from The COPAINS Pilot Survey: Four new brown dwarfs and a high companion detection rate for accelerating stars,” M Bonavita et al., 2022 May 10, Monthly Notices of the Royal Astronomical Society