LIGO’s historic breakthrough continues: After a pause, LIGO recently resumed operations following significant improvement. The improved version is about 40% more sensitive than its predecessor, allowing it to detect weaker and more distant gravitational waves. The latest observation run began on April 1, 2023 and is expected to last approximately two years. During this period, LIGO will actively search for gravitational waves generated by phenomena such as black hole mergers, neutron star collisions, and supernovae.
“Our LIGO teams have worked through difficulties for the past two years to be ready for this moment, and indeed we are ready: our engineering run leading up to tomorrow’s official start in 04 has already revealed a number of candidate events, which we have shared with the astronomical community,” says Albert Lazzarini of Caltech, deputy director of the LIGO Laboratory.
Source: Caltech/Caltech/MIT/LIGO Lab
The collaboration between LIGO, Virgo and KAGRA is crucial to unraveling the mysteries of gravitational waves. These detectors work together to decipher the subtle perturbations in space-time caused by massive celestial objects. To improve the sensitivity of the instruments, additional vacuum tubes with mirrors have been built as part of the upgrade. These vacuum tubes reduce noise and minimize mirror jitter, allowing for more accurate measurements.
“In recent months, we have identified several noise sources and made good progress in sensitivity, but we have not yet reached the design goal.“stated newly elected Virgo spokesperson Gianluca Gemme. “We are convinced that achieving the best detector sensitivity is the best way to maximize its discovery potential.
While Virgo experienced restart delays due to technical issues, KAGRA resumed operations on May 24. KAGRA will join LIGO’s ongoing experimental run before undergoing recommissioning the following month. Looking ahead, LIGO-Virgo-KAGRA is planned to join LIGO-India later in the decade, and some components of LIGO-India will be built using spare parts from the original LIGO project. This collaborative effort demonstrates the continued advances in gravitational wave research and the promising future discoveries it brings.
What is LIGO?
The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a leading scientific experiment and observatory based in Hanford, Washington and Livingston, Louisiana. Its main objective is to detect gravitational waves, which are ripples in space-time caused by the movement of massive objects. LIGO has played a fundamental role in the field of astronomy since its inception.
LIGO was proposed in 1984 by Rainer Weiss, Kip Thorne and Ronald Drever. Construction of the observatories began in 1994, with the first completed in 2002 in Hanford and the second in 2005 in Livingston. These observatories use laser interferometry, using mirrors placed four kilometers away to detect even the slightest changes in distance.
Source: Caltech/Caltech/MIT/LIGO Lab
On September 14, 2015, LIGO achieved a breakthrough by directly detecting gravitational waves for the first time. This historic detection, known as GW150914, was caused by the merger of two black holes located 1.3 billion light years away. Since then, LIGO has continued to make groundbreaking discoveries, including detecting neutron star mergers and collisions between black holes of different masses.
The impact of LIGO’s gravitational wave detection on astronomy has been profound. It has allowed scientists to observe and study some of the most powerful events in the universe, such as the merger of black holes and neutron stars. Additionally, LIGO has paved the way for other gravitational wave observatories such as Virgo in Italy, GEO600 in Germany, and KAGRA in Japan, which together improve our ability to detect gravitational waves from a broader range of sources.