LIGO has found gravitational waves that were formed during collision of two massive black holes. LIGO’s detection was superb, but one must have a look at the name of the detector for a while, it’s Laser Interferometer Gravitational wave Observatory. This clearly says LIGO is first of all an observatory.

It’s a kind of telescope that uses gravitational waves and not electromagnetic waves. It is notable that if you find a gravitational wave and know the source of the wave, you could observe the event using an electromagnetic telescope.

Presently, we have two LIGO detectors, one is present in Louisiana and the other is in Washington. Earth has other gravitational wave detectors too however, they weren’t operational when LIGO measured a signal. There are a couple of significant reasons of having more than one detector.

Firstly, using two detectors astronomers can compare the results to ensure that both possess a signal. This can eradicate the possibility that something local resulted into a vibration that seemed like a gravitational wave.

Once astronomers know the variation in times for the two detectors, they can get a clue of what direction the gravitational wave belonged to.

Einstein’s general theory of relativity shed light on gravitational waves. Nearly a century back, Albert Einstein originally had the idea of emergence of gravitational waves from his theory of relativity. According to scientists gravitational waves are ‘the ripples in fabric of space-time’.

The theory predicted that gravitational waves originate from fast moving huge objects. Emission of nanohertz gravitational waves takes place from pairs of supermassive black holes orbiting one another, each containing millions or a billion times more mass as compared to the ones detected by LIGO.