Dense filaments of gas in the IC5146 interstellar cloud can be seen clearly in this image taken in infrared light by the Herschel space observatory. Stars are forming along these filaments. The blue region is a stellar nursery known as the Cocoon nebula.

Herschel has revealed that clouds between stars contain networks of tangled gaseous filaments. Intriguingly, each filament is approximately the same width, hinting that they may result from interstellar sonic booms throughout our Milky Way galaxy.

The filaments are huge, stretching for tens of light years through space, and Herschel has shown that newborn stars are often found in the densest parts of them. One filament imaged by Herschel in the Aquila region contains a cluster of about 100 infant stars.

Such filaments in interstellar clouds have been glimpsed before by other infrared satellites, but they have never been seen clearly enough to have their widths measured. Now, Herschel has shown that, regardless of the length or density of a filament, the width is always roughly the same.

The team suggests that as sonic booms from exploding stars travel through the clouds, they lose energy and, where they finally dissipate, they leave these filaments of compressed material.

This image was taken by Herschel at infrared wavelengths of 70, 250 and 500 microns.

Herschel is a European Space Agency cornerstone mission, with science instruments provided by consortia of European institutes and with important participation by NASA. NASA's Herschel Project Office is based at NASA's Jet Propulsion Laboratory. NASA's Jet Propulsion Laboratory in Pasadena, Calif., developed and built the "spider web" bolometers for Herschel's spectral and photometric imaging receiver (SPIRE) instrument, which are 40 times more sensitive than previous versions. It also developed and built mixers, local oscillator chains and power amplifiers for the heterodyne instrument for the far infrared (HIFI). The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the United States astronomical community. Caltech manages JPL for NASA.

More information about NASA's role in the mission is at http://www.herschel.caltech.edu/.