Gravitational Waves

Gravitational waves are curvature disturbances in space-time due to accelerated mass. Gravitational waves are invisible but incredibly fast ripples in space. It travels at speed of light which is 186,000 miles per second. These waves stretch and compress everything in their path as they pass.


Gravitational waves are “waves” in the structure of space-time caused by the most energetic and violent processes in the universe. As an object accelerates, it creates ripples in space-time, much like a boat makes ripples in a pond. These space-time waves are called gravitational waves. They are so weak that they are very difficult to find. Two objects orbiting each other in a flat orbit, such as planets or star systems orbiting the Sun, or the union of two black holes, emit gravitational waves.

The existence of gravitational waves was predicted by Albert Einstein in the year 1916 with his general theory of relativity. Einstein’s mathematics has shown that large accelerating objects such as neutron stars and black holes orbiting each other disturb space-time, producing “waves” in distorted space from their sources. In addition, these waves travel through the universe at the speed of light. G-waves can penetrate any substance in between without much scattering. Light from distant stars can be blocked by interstellar dust, but gravitational waves pass essentially unobstructed. This feature allows G Waves to send information about astronomical phenomena that humans have never observed before. Colliding black holes send waves to space-time that can be detected on Earth. Advanced LIGO which stands for Advanced Laser Interferometer Gravitational-Wave Observatory and is located in Washington and Louisiana has observed gravitational waves

Observed Phenomenon

The phenomenon discovered was the collision of two black holes. Scientists used the world’s most modern detectors to listen to 1 / 20,000 seconds while two giant black holes orbit each other. At the beginning of the signal, their calculations told them how the stars would go down. The two objects initially circled each other 30 times per second. By the end of the 20ms data snapshot, the two accelerated to 250 times per second before the final collision, resulting in a violent and dark merger. Scientists have discovered this catastrophic event using equipment that is sensitive enough to detect changes in the distance between the solar system and the nearest star. This is 4 light-years in human hair thickness. It took only 20 milliseconds to capture the union of two black holes 1.3 billion light-years apart.

About LIGO and Interferometer

Interferometers are inspection tools used in technology and science. They are called interferometers because they work by fusing two or more light sources into an interferometric pattern that can be measured and analyzed. The interferometer-generated interference patterns contain information about what is being inspected or what is happening. These are often used to make very small measurements that cannot be obtained otherwise. Powerful enough to detect gravitational waves, LIGO’s interferometers have been designed to measure distances of 1 / 10,000 of the width of a proton.

The Laser Interferometer Gravitational Wave Observatory (LIGO) was designed to open up the field of gravitational wave astronomical physics by directly detecting gravitational waves predicted by Einstein’s general theory of relativity. LIGO’s multi kilometre gravitational wave detector uses laser interferometry to measure small spatiotemporal ripples caused by the passage of gravitational waves from various cataclysmic cosmic sources.