The Enormous Gas Filament Mirages Galaxy Clusters

For the initial time, ESA's Planck space telescope has been detected a bridge of hot gas between a pair of galaxy clusters 10 million light-years apart. A bell 399 and a bell 401, each containing 100’s of galaxies, are billions of light years a path. The being there of hot gas linking them had previously been oblique at in X-ray data from ESA's XMM-Newton, but is now established."Planck is helping to expose hidden material between galaxy clusters that we couldn't observe clearly before," says James Bartlett scientist of NASA's Jet Propulsion Laboratory.

In the before time universe, filament of gaseous matter pervaded the space in a giant web, with clusters finally forming in the densest nodes. The gas that remains is easiest to spot between interact galaxy clusters, where the filament are dense and heated up.

Ambitious Hubble Survey Obtaining New Dark Matter Census

The distorted shapes in the cluster are distant galaxies from which the light is bent by the gravitational pull of an invisible material called dark matter within the cluster of galaxies. This cluster is an early target in a survey that will allow astronomers to construct the most detailed dark matter maps of more galaxy clusters than ever before.

These maps are being used to test previous, but surprising, results that suggest that dark matter is more densely packed inside clusters than some models predict. This might mean that galaxy cluster assembly began earlier than commonly thought.

The multi-wavelength survey, called the Cluster Lensing And Supernova survey with Hubble (CLASH), probes, with unparalleled precision, the distribution of dark matter in 25 massive clusters of galaxies. So far, the CLASH team has observed six of the 25 clusters.Dark matter makes up the bulk of the universe’s mass, yet it can only be detected by measuring how its gravity tugs on visible matter and warps space like a fun house mirror so that the light from distant objects is distorted.

Detailed Dark Matter Map Yields Clues to Galaxy Cluster Growth

Astronomers using NASA's Hubble Space Telescope took advantage of a giant cosmic magnifying glass to create one of the sharpest and most detailed maps of dark matter in the universe. Dark matter is an invisible and unknown substance that makes up the bulk of the universe's mass. The new dark matter observations may yield new insights into the role of dark energy in the universe's early formative years. The result suggests that galaxy clusters may have formed earlier than expected, before the push of dark energy inhibited their growth. A mysterious property of space, dark energy fights against the gravitational pull of dark matter. Dark energy pushes galaxies apart from one another by stretching the space between them, thereby suppressing the formation of giant structures called galaxy clusters.

One way astronomers can probe this primeval tug-of-war is through mapping the distribution of dark matter in clusters. A team led by Dan Coe at NASA's Jet Propulsion Laboratory in Pasadena, Calif., used Hubble's Advanced Camera for Surveys to chart the invisible matter in the massive galaxy cluster Abell 1689, located 2.2 billion light-years away. The cluster's gravity, the majority of which comes from dark matter, acts like a cosmic magnifying glass, bending and amplifying the light from distant galaxies behind it. This effect, called gravitational lensing, produces multiple, warped, and greatly magnified images of those galaxies, like the view in a funhouse mirror. By studying the distorted images, astronomers estimated the amount of dark matter within the cluster. If the cluster's gravity only came from the visible galaxies, the lensing distortions would be much weaker.

Based on their higher-resolution mass map, Coe and his collaborators confirm previous results showing that the core of Abell 1689 is much denser in dark matter than expected for a cluster of its size, based on computer simulations of structure growth. Abell 1689 joins a handful of other well-studied clusters found to have similarly dense cores. The finding is surprising, because the push of dark energy early in the universe's history would have stunted the growth of all galaxy clusters. "Galaxy clusters, therefore, would had to have started forming billions of years earlier in order to build up to the numbers we see today," Coe explains. "At earlier times, the universe was smaller and more densely packed with dark matter. Abell 1689 appears to have been well fed at birth by the dense matter surrounding it in the early universe. The cluster has carried this bulk with it through its adult life to appear as we observe it today."