ESA’s Herschel Infrared Space Telescope has combined images from two of its instruments to reveal rampant star formation happening in an area until now believed to be just cold gas.
The Spectral and Photometric Imaging REceiver, SPIRE, and Photoconductor Array Camera and Spectrometer, PACS were turned on a nebula deep in the constellation of the southern cross, thousands of light years from us. The PACS instrument, observing at cooler wavelengths 250 and 500 microns has had its data coloured red and the SPIRES three wavelengths between 70 and 170 microns has had its signals coded blue in the combined image.
It is often difficult to tease details like this from large clouds of dust in the galaxy as there are so many such clouds in every direction it is difficult to say whether or not what you’re seeing in infrared relates to the visually observed nebula or something in front or behind it. Herchel’s high resolution data, however, is unambiguous.