The three large observatories located in Italy, Washington, and Louisiana, along with a new one from Japan, will be part of the new global array of highly potent observatories. The array is designed to detect ripples in the fabric of space and time.
The network will improve a field of science that came to life four years ago when the Laser Interferometer Gravitational-Wave Observatory (LIGO) resolved an enigma posed by Albert Einstein approximately 100 years ago.
Back in 1916, Einstein suggested that accelerating massive objects, such as neutron stars or black holes, would generate ripples, or waves, in the fabric of space and time. It seemed like Einstein was correct for that long of a time. In the late 1990s, LIGO’s machines located in Louisiana and Washington were designed with the aim to detect signals Einstein thought we would never pick up.
At last, after 13 years of nothing, LIGO identified its first gravitational waves in September 2015. They were signals from two black holes merging about 1.3 billion light-years away. Since then, LIGO and Virgo, the observatory located in Italy, have identified two other phenomenal collisions.
Now, LIGO and Virgo are getting another companion: the Kamioka Gravitational-Wave Detector (KAGRA), located in Japan.
Scientists expect to pin down the location of huge collisions with three times more precision with the help of KAGRA. This way, the new global array could eventually identify 100 collisions per year, Vicky Kalogera, an astrophysicist at Northwestern University, and LIGO said.
KAGRA Helps With The Noise Issues
KAGRA is scheduled to come online in December of this year. After scientists improve its instruments, they expect it to fully function at its highest rate sometime in 2020. The Japanese observatory will enhance the precision of the global gravitational-wave detection array by making it more stable.
The new detector will use modern techniques to make it less prone to false identifications. Due to the fact that LIGO and Virgo are incredibly sensitive, they can easily be riled by the vibration of trucks on nearby roads or even a simple breeze. That is because when a wave passes by, the arms’ length adjusts by less than 1/10,000th of the width of a proton particle. Therefore, even the microscopic motion of an atom in the observatory’s mirrors can imitate the signal of a gravitational wave.
This is the reason why LIGO is placed in two different locations, and also works with Virgo. If they all identify a signal at the exact same time, that is more probably a gravitational wave passing through the planet.
KAGRA will have another tool that will help with the verification of those detections. The instrument will function underground to be better isolated from the impediment of wind, Earth’s echoes, and passing cars.
The Japanese observatory will also be the first detector to cryogenically chill its mirrors to reduce noise from the mirrors’ own atoms. To cryogenically chill something is the practice of utilizing liquefied gas to reach temperatures below -150 degrees Celsius (-238 degrees Fahrenheit).
Another observatory, LIGO India, is scheduled to join the global gravitational-wave array in 2025.