What is a liquid galaxy

New Sky Atlas contains 560 million stars and galaxies

Pasadena (USA) - In 2010, the American satellite WISE photographed the sky in the infrared range for ten months. Now NASA has published the collected data as a sky atlas and object catalog. The atlas of the infrared sky consists of over 18,000 images, the catalog contains the data of more than 560 million stars and galaxies. The atlas and catalog are accessible not only to astronomers but also to the public via the WISE mission's homepage.

Sky in the infrared range

"With the publication of the complete sky-wide catalog and atlas, WISE joins the pantheon of great sky surveys that have led to so many remarkable discoveries about the universe," said Roc Cutri of the California Institute of Technology in Pasadena, who manages the processing and archiving of the WISE data. WISE sent a total of 2.7 million images corresponding to 15 trillion bytes of data to Earth. Scientists from all over the world can now view the data and, Cutri hopes, gain new knowledge about known objects, but also discover new, previously unknown phenomena.

The $ 320 million satellite was launched on December 14, 2009 and began its scientific observations in January 2010. With his 40 centimeter infrared telescope, he photographed the entire sky in four narrow wavelength ranges within ten months. In October 2010, the liquid hydrogen used as a coolant was exhausted and WISE's primary scientific mission ended. In the “warm” state, the satellite searched for small celestial bodies in the vicinity of Earth's orbit for four more months before it was switched off on February 17, 2011.

WISE has not only delivered the most extensive celestial catalog in the infrared range to date, but has also discovered numerous new celestial objects. These include extremely cool brown dwarfs - celestial bodies that are larger than planets but do not have sufficient mass to generate energy through nuclear fusion like stars. In addition, WISE has detected 33,500 previously unknown asteroids in the solar system.