The Expansion of the Cosmos

The night sky’s plethora of heavenly bodies has become a little more discernible as two astronomers from the US National Optical Astronomy Observatory discover a binary black hole. The two scientists, Todd Boroson and Tod Lauer, both from Tucson Arizona, published their findings in the journal Nature.
Their discovery of a double black hole system is in line with the theory of the growth of galaxies, which postulates that each galaxy houses a black hole at its centre. It is believed that as these two black holes begin to merge they will form a bigger galaxy.
Because matter entering a black hole gives off electromagnetic waves that can be recorded here on earth, astronomers use the Doppler Effect to determine which direction the black holes are moving, and how fast they’re moving. Formerly revealed by the Austrian physicist and mathematician, Christian Doppler, the Doppler Effect is best demonstrated by listening to an ambulance’s siren becoming louder as the vehicle gets closer and quitter as it passes. The sound waves emitted from the ambulance, the light waves, and electromagnetic waves emitted from the black hole, communicate how fast the bodies producing the waves are moving. When the waves move toward the listener they are squeezed together producing a blue shift, and when they are in retreat they fan out and produce a red shift, which are both detected by sophisticated instruments. These shifts allow scientists to determine how fast the bodies are moving.
It is estimated that less than a third of a light-year separates these two behemoth heavenly bodies. The distance separating these two quasars is believed to be closer than the binary system found by the Chandra X-ray Observatory in 2003. Because of the distance they are from one another, and the massiveness of each black hole, which is estimated to be between 20 million to 1 billion times bigger than earth’s sun, it takes them one hundred years to circle one another.
Unlike the 2003 discovery of a binary black hole system, this discovery is more revolutionary because the evidence is much stronger and the pairing is tighter. The first discovery of a binary black hole, at a distance of about 400 million light-years, was NGC 6240. Though the discovery of the two black holes, which are about 3,000 light-years apart, was breath taking in 2003, the recent discovery is hoped to produce even better data. The data compiled is expected to help astronomers postulate how the cosmos are expanding.