The above image, taken by the Herschel Space Observatory, shows a giant, galaxy-packed filament ablaze with billions of new stars. The filament connects two clusters of galaxies that, along with a third cluster, will smash together in several billion years and give rise to one of the largest galaxy superclusters in the universe. A white circle outlines the 8 million light-year-long intergalactic filament in each image. In visible light, the filament does not stand out because dust obscures the star-formation activity in distant galaxies. Image Credit: ESA/NASA/JPL-Caltech/CXC/McGill University
The Herschel Space Observatory has discovered a giant, galaxy-packed filament ablaze with billions of new stars. The filament connects two clusters of galaxies that, along with a third cluster, will eventually smash together, creating one of the largest galaxy superclusters in the universe.
To refresh, Herschel is a European Space Agency (ESA) mission with important contributions by NASA. Launched May 2009 and named after British astronomer William Herschel, the orbital observatory studies the universe in the far-infrared and submillimeter portions of the electromagnetic spectrum.
The filament observed by Herschel is the first structure of its kind seen in a critical era of cosmic buildup when colossal collections of galaxies called superclusters began to take shape. The glowing galactic bridge offers astronomers a unique opportunity to explore how galaxies evolve and merge to form superclusters.
The mission team members are excited about the filament, because they think the intense star formation they see in its galaxies is related to the consolidation of the surrounding supercluster. The details appear in a new paper published April 3rd in the Astrophysical Journal Letters by members of the Herschel mission team.
The intergalactic filament, which contains hundreds of galaxies, spans 8 million light-years and links two of the three clusters that make up a supercluster known as RCS2319. This emerging supercluster is an extremely rare, distant object whose light has taken more than seven billion years to reach Earth.
RCS2319 is the subject of a huge observational study. Previous observations in visible and X-ray light had found the cluster cores and hinted at the presence of a filament. It was not until astronomers trained Herschel on the region, however, that the intense star-forming activity in the filament became clear. Dust obscures much of the star-formation activity in the early universe, but telescopes like Herschel can detect the infrared glow of this dust as it is heated by nascent stars.
The amount of infrared light suggests that the galaxies in the filament are cranking out the equivalent of about 1,000 solar masses (the mass of our sun) of new stars per year. For comparison's sake, our Milky Way galaxy is producing about one solar-mass worth of new stars per year. Researchers chalk up the blistering pace of star formation in the filament to the fact that galaxies within it are being crunched into a relatively small cosmic volume under the force of gravity. By studying the filament, astronomers will be able to explore the fundamental issue of whether "nature" versus "nurture" matters more in the life progression of a galaxy.
There is lots more to read in the new paper. Please check it out. "The Herschel Filament: A Signature of the Environmental Drivers of Galaxy Evolution During the Assembly of Massive Clusters at z= 0.9*." April 3, 2012. Astrophysical Journal Letters, Volume 749, Number 2:
And now, the mission particulars...
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, Pasadena, California. JPL contributed mission-enabling technology for two of Herschel's three science instruments. 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 mission information is online at http://www.herschel.caltech.edu/ , www.nasa.gov/herschel and www.esa.int/SPECIALS/Herschel .
There is lots more to read in the team's paper. Please check it out. "The Herschel Filament: A Signature of the Environmental Drivers of Galaxy Evolution During the Assembly of Massive Clusters at z= 0.9*." April 3, 2012. Astrophysical Journal Letters, Volume 749, Number 2: