Ligo starts fourth run to catch gravitational waves, unravel secrets of universe

The fourth run, since the observatory picked up the first gravitational waves in 2015, is the most sensitive one and will last 20 months.

The global network of gravitational-wave detectors that have their ears pierced to the faintest rumblings happening in the far end of the vast universe has commenced their latest run.

The much awaited start of LIGO:

The Laser Interferometer Gravitational-Wave Observatory (LIGO) began a new observing run to explore the secrets of the universe after going through a major upgrade with further sensitive instruments and other improvements to boost the search for gravitational waves.

The fourth run, since the observatory picked up the first gravitational waves in 2015, is the most sensitive one and will last 20 months, including up to two months of commissioning breaks.

About gravitational waves:

The ripples in the fabric of spacetime caused by the acceleration of massive objects, gravitational waves, were first conceptualised by Albert Einstein as part of his theory of relativity. The gravitational waves are generated by colliding black holes and other extreme cosmic events.

Gravitational waves can be detected through their effect on the measurement of space and time. The most common method used to detect them is through the use of interferometers, which measure the ripples in space and time by measuring the change in length of two perpendicular arms of the interferometers.

The recent run:

The new run will see an increase in sensitivity of approximately 30 percent. The team said that the detectors will observe a larger fraction of the universe than before and will pick up gravitational-wave signals at a higher rate, detecting a merger every two or three days.

The increase in sensitivity will help the teams extract more physical information from the data, allowing them to better test Albert Einstein's general theory of relativity and infer the true population of dead stars in the local universe. By observing gravitational waves, we can gain insights into the nature of these astrophysical objects and the fundamental laws of physics.

Words from Albert Lazzarini:

"Our LIGO teams have worked through hardship during the past two-plus years to be ready for this moment, and we are indeed ready," Caltech's Albert Lazzarini, the deputy director of LIGO, said in a statement. The observations will focus on black hole binary systems and even neutron stars.

India's own LIGO:

Work is underway to build India's first gravitational wave detector in Maharashtra. The centre had in April allocated Rs 2,600 crore to construct the observatory by 2030. It will observe the gravitational waves travelling in the vastness of space from some of the most violent and energetic processes in the Universe and hitting Earth.