New Discovery from the Laser Interferometer Gravitational Wave Observatory (LIGO)
Recently the US-based ‘Laser Interferometer Gravitational-Wave Observatory (LIGO)’ has detected a new source of gravitational waves from a neutron star-black hole (NS-BH) collision.
Scientists have previously looked for signs of colliding black holes and colliding neutron stars, but have not yet confirmed the merger of a black hole with a neutron star.
Key points
- Neutron stars are formed when a massive star is depleted of energy.
- Scientists have observed not only one, but two rare events in which gravitational waves (Gw) each have been recorded.
- These were detected by LIGO based in the United States and Virgo based in Italy.
- The technique used to detect the signal is called matched filtering.
Gravitational waves
- Gravitational waves are ‘waves’ in space-time, caused by some of the most violent and energetic processes in the universe and traveling at the speed of light.
- They carry with them information about their cataclysmic origins as well as invaluable differences in the nature of gravity.
They are created when:
- The body moves at a very high speed,
- When a star explodes asymmetrically (called a supernova),
- When two massive stars orbit each other,
- When two black holes orbit each other and merge.
Albert Einstein predicted the existence of gravitational waves in his theory of general relativity in the year 1916.
LIGO
- Gravitational waves were first detected in 2015 by LIGO based in the US. LIGO is the world’s largest gravitational wave observatory, with two giant laser interferometers installed.
- LIGO has 3 other subsidiary facilities namely: Vargo in Italy, GEO600 in Germany and KAGRA in Japan.
- Additionally, LIGO-India is an Indo-US joint detector installed in Hingoli district of Maharashtra.
Source – The Hindu
