Dark matter mapped in 3-D detail
Invisible web serves as scaffolding for ?ordinary? matter, scientists say
This illustration shows the three-dimensional distribution of dark matter in a patch of the universe, going back from a nearby region in recent time (on the left) to a distant region about 6.5 billion years ago (on the right). The chart indicates that the distribution of mass has become increasingly clumpy
[…]
The findings announced Sunday provided a “first glimpse of the cosmic web” in true-to-life, three-dimensional detail, said Caltech’s Richard Ellis, another member of the COSMOS team.
The lead author of the Nature paper, Caltech astronomer Richard Massey, said the COSMOS study provides the best confirmation that dark matter determines “the underlying structure of space.” Galaxies as well as primordial globs of gas and dust form “within this dark-matter scaffolding,” he said.
[…]
Even though the matter itself couldn’t be seen, astronomers detected its effect by analyzing the gravitational effect of that matter on light rays from more distant light sources. As light rays from faraway objects passed by, the unseen matter acted like a gravitational lens, bending and distorting those rays in characteristic ways.
Observations from other instruments, particularly the XMM-Newton space telescope, provided information about how far the light rays had traveled. The COSMIC team combined the data about the distortions with the data about the distances, then produced a 3-D map by building up separate layers. The process is similar to the way a 3-D map of the human body can be built up in a medical CT scan.
[…]
Read more: Science, Physics, Astronomy, Cosmology, Dark matter, Universe, Space, Maps
