Chance discovery reveals star factories in the distant Universe

This composite image shows the discovery of the distant galaxy SMM J2135-0102. Left : a view of galaxy cluster MACS J2135-010217 (centre), which is gravitationally lensing SMM J2135-0102. Top right : SMM J2135-0102 was first discovered in submillimetre-wavelength observations (shown in red) with the LABOCA camera on the Atacama Pathfinder Experiment (APEX) telescope. Bottom right : follow-up observations with the Submillimeter Array (in red) revealed the clouds where stars are forming in the galaxy with great precision. Our view of the galaxy is magnified by gravitational lensing, which also produces a doubling of the image ; the apparent eight regions in the Submillimeter Array observations actually represent four distinct regions of star formation in the galaxy.