Man’s quest to fully understand the universe has had a major breakthrough in the area of gravity and comprehending its nature. Albert Einstein made a prediction on the existence of gravitational waves in his general theory of relativity almost 100 years ago, stating if two massive objects accelerated towards each other, their immense gravity would send out enormous ripples that would distort the fabric of space. Technology wasn’t advanced or sensitive enough to detect these ripples, until now at the Laser Interferometer Gravitational-Wave Observatory (LIGO) facility in the USA where they managed to observe these waves.

1.3 billion years ago, there were two black holes that were orbiting each other, eventually merging into one and forming one giant black hole. Black holes are extremely dense remnants of supermassive stars that collapsed and caved in on themselves. They bend space-time more than any other object in the universe, so when two of them (each one about 30 times the mass of the sun) collided, it created a colossal disturbance. This was regarded as one the most cataclysmic event ever recorded, which sent relatively massive gravitational waves at the speed of light throughout parts of the universe.

The LIGO facility detected these waves using their laser interferometer, which is comprised of two light beams, a few mirrors and a detector. The light beams travel in directions perpendicular to each other and are reflected back by the mirror. When a gravitational wave passes over, it stretches the Earth in one direction and compresses it at a right angle. This therefore means that one of the light beams travel a larger distance and one of them travels a shorter distance, which can be measured using a detector. The change in distance is a direct result of space time around the Earth contracting and elongating! The difference in the Earth’s length was miniscule at about one thousandth the diameter of a neutron, proving how sensitive and accurate LIGO is.

This discovery is hugely significant as it gives scientists another perspective from which to observe the universe. Until now, our understanding of the universe was limited to what we could discern through studying the electromagnetic waves (light) being emitted by astronomical bodies. These waves could be the key to discovering the elusive “gravitons” that are theorised to be the particles responsible for gravity, which could then unite the four fundamental forces, creating the grand unified theory. Through observing gravitational waves we can also understand the complex physics of the stars. “Listening” to the gravitational wave bursts of dying stars could tell us why they explode in violent supernova’s and what causes them to form such complicated and intriguing structures such as neutron stars and black holes. As well as this, scientists could possibly calculate the rate of expansion of the universe more accurately and perhaps look into the past and see the big bang itself.

Clearly this discovery willl influence our understanding of space and aid us in our quest to unlockthe secrets of the universe.