Despite still not having physical evidence of dark matter, researchers at NASA continue to look for the elusive substance. Theorized to make up about 80 percent of all matter in the universe, dark matter is also an essential component in the formation and rotation of the galaxies. So how close is NASA to finding the mysterious dark matter?
In the ongoing search for dark matter, something that does not give off or absorb light, scientists believe Gamma-rays will be able to reveal its particles. Interacting with the universe through gravity, dark matter is said to consist of hypothetical particles by the name of Axons. A Fermi Gamma-ray Space Telescope would be used to investigate if dark matter does indeed carry these Axons. An infographic on how this works may be seen here. So far, the search has not been fruitful.
On the other hand where Gamma-ray is concerned. With the help of the Fermi Gamma-ray Space Telescope, scientists at the space agency had discovered "the first gamma-ray binary in another galaxy" which is reportedly "the most luminous one ever seen."
A Gamma-ray binary is the name given to a system composed of two stars. One is a normal star while the other is either a black hole or a neutron star. The radiative output of this system is dominated by gamma-rays which is the highest energy form of light. The largest Gamma-ray binary discovered is found in the Large Magallanic Cloud, located 163,000 light years away.
"Fermi has detected only five of these systems in our own galaxy, so finding one so luminous and distant is quite exciting. Gamma-ray binaries are prized because the gamma-ray output changes significantly during each orbit and sometimes over longer time scales. This variation lets us study many of the emission processes common to other gamma-ray sources in unique detail," explains Robin Corbet, the lead researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland.