Key Takeaways:
- X-rays reveal invisible cosmic information for astronomers, unlike their skeletal connotation for commoners.
- The largest ever X-ray map of the universe has been released, identifying over 700,000 supermassive black holes and 900,000 cosmic sources.
- The eROSITA telescope on a Russian-German satellite collected the data for this record-breaking X-ray map.
- The map includes exotic celestial objects besides the supermassive black holes and high-energy sources, like X-ray emitting stars in our Milky Way.
- This X-ray survey discovered more sources in 6 months than previous flagship missions in 25 years.
The word ‘X-ray’ for commoners has (literal) skeletal connotations. When we hear the word “X-ray,” we picture ourselves staring at our bones on dark film. But for astronomers, X-ray represent a treasure trove of cosmic information. An object that is invisible at “normal” light wavelengths may release an X-ray and reveal its own mysteries.
As a full-fledged field, X-ray astronomy attracts professionals who dedicate their careers to it. The universe’s largest-ever X-ray map has just been made public. There are over 700,000 supermassive black holes and over 900,000 high-energy cosmic sources on the map.
The German consortium “eROSITA” released the data. The X-ray map has data collected by eROSITA X-ray telescope which is fitted on Spektrum-RG, a Russian-German satellite.
The Max Planck Society in Germany, which helped the mission, said from its official X handle that the eROSITA All-Sky Survey Catalogue (eRASS1) is the largest collection of X-ray sources ever published till now.
“An X-ray image of half the #universe: the first publication of the eROSITA sky-survey data release makes public the largest ever catalogue of high-energy cosmic sources,” according to the post by The Max Planck Society.
“In the first six months of observation, eROSITA has already discovered more X-ray sources than have been known in the 60-year history of X-ray astronomy,” it said.
The observations were conducted by the eROSITA telescope from December 12, 2019, to June 11, 2020.
The 710,000 supermassive black holes, that is. The high-energy cosmic sources (more than 900,000) also comprised 180,000 stars that emitted X-rays. The Milky Way contains these stars.
Furthermore, 12,000 galaxy clusters and several X-ray emitting celestial objects belonging to other exotic classes are included in the map.
Principal investigator Andrea Merloni of eROSITA said, “These are mind-blowing numbers for X-ray astronomy,” as quoted by The Max Planck Society.
“We’ve detected more sources in 6 months than the big flagship missions XMM-Newton and Chandra have done in nearly 25 years of operation,” she stated.
