An enormous amount of gravity from a cluster of distant galaxies causes space to curve so much that light from more distant galaxies is bent. This “gravitational lensing” effect has allowed University of Copenhagen astronomers to observe the same exploding star –SN Requiem–in three different places in the heavens, and may help solve the mystery of cosmic expansion and reveal the nature of dark matter and dark energy.
Another amazing week in our Universe beyond –from a new type of habitable planet to China’s plan for a spacecraft 30 times the size of the ISS to the new reality of UFOs and the detection of gravitational waves that could be from dark matter particles.
“We use special telescopes to catch X-ray light in the sky, and while looking at these X-rays, the telescopes noticed an unexpected feature and captured a spectrum of light, which is not produced by any known atomic emission,” said University of Miami astrophysicist Nico Cappelluti about a signal first detected in 2014. “This emission line is now called the 3.5 kiloelectron volt (keV). One interpretation of this emission line is that it’s produced by the decay of dark matter.”
“The universe resembles a Swiss cheese – but one with huge holes: Large areas in space are absolutely empty. In between, thousands of galaxies crowd in a comparatively small space. These clusters are connected by highways of thin matter gas, like the gossamer filaments of a spider’s web,” reports The University of Bonn about gargantuan filaments in the universe that fueled the formation of clusters of galaxies and galaxies at places where the filaments crossed, creating dense regions of matter –the cheese.
Astronomers studying the motions of galaxies and the character of the cosmic microwave background radiation came to realize in the last century that most of the matter in the universe was not visible. About 84 percent of the matter in the cosmos is dark matter, much of it located in halos around galaxies. It was dubbed dark matter because it does not emit light, but it is also mysterious: it is not composed of atoms or their usual constituents like electrons and protons.
“The interesting thing is: we have no idea!” says Pieter van Dokkum, Sol Goldman Professor of Astronomy at Yale University, who wrote in an email to The Daily Galaxy about why ultra-diffuse galaxy DF2 contains no dark matter. “The existence of this galaxy shows that there is another pathway to creating galaxies than our standard picture, but what that might be is anyone’s guess.”