LIGO gravitational wave detector is back, ready to detect more colliding black holes & neutron stars

LIGO has already begun its fourth run, while Virgo is set to join later in the year. KAGRA has joined for one month starting yesterday and should rejoin later in the fourth run after some upgrades.

“Our LIGO teams have worked through hardship during the past two-plus years to be ready for this moment, and we are indeed ready: our engineering run leading up to tomorrow’s official start of 04 has already revealed a number of candidate events, which we have shared with the astronomical community,” Albert Lazzarini, the deputy director of the LIGO Laboratory, in a press statement released before the beginning of the third run.

According to Lazzarini, the detectors will begin the run with a 30 per cent increased sensitivity. This means that they will be able to observe a larger fraction of the universe than before and will pick up gravitational-wave signals at a higher rate.

Apart from being able to detect a larger fraction of the universe, LIGO will be able to extract more physical information from the data thanks to its sensitivity. This will let scientists test Albert Einstein’s general theory of relativity and infer the real population of dead stars in the local universe.

The Indian government has given the go-ahead for a LIGO-India project to be set up in the Hingoli district of Maharashtra, which is about 450 kilometres east of Mumbai. LIGO-India could be the fifth node of the international network of gravitational wave observatories.

These observatories have instruments so sensitive that they can produce false readings due to the influence of earthquakes, landslides, other natural events and even the movement of trucks. This is where multiple observatories can be helpful in revalidating the signal.