Liupanshui, laser interferometer gravitational-wave observatory.

There are now four countries in the world with six gravitational-wave observatories.

Aramco has two 4 km and 2 km arms (LHOs) in Washington State, and one 4 km Observatory (LLO) in Washington State.

They are all part of the LIGO detection system, the most advanced and sensitive gravitational wave detection device to date, and have been upgraded all the time, with a 20-fold increase in laser power until now, and a 10-fold increase in sensitivity compared to the initial version.

THEN THERE IS THE VIRGIN OBSERVATORY IN PISA, ITALIAN, WITH 3 KILOMETERS OF ARMS, WHICH OFFICIALLY JOINED THE LIGO SYSTEM IN AUGUST LAST YEAR TO JOINTLY DETECT GRAVITATIONAL WAVES, AND THE SENSITIVITY IS COMPARABLE TO THAT OF ARAMCO'S THREE.

Finally, the GEO600 observatory in Germany, with a length of only 600 meters in both arms, has been in operation since 2002, but its sensitivity is not high, failures are frequent, and its scientific value is extremely limited.

In addition to them, the island nation used TAMA300 gravitational wave detector in 2000, but it was discontinued after LIGO detected gravitational waves in 2015 and converted into a test bed for other purposes.

The government of the island nation also started the construction of the Kamiokande Gravitational Wave Detector (KAGRA) in 2010, but it is not yet complete and is expected to be put into operation in 2020.

There are many and complex indicators to define the performance of laser interferometric gravitational-wave observatories, but the most obvious and largest is the length of the double arm, that is, the length of the interference arm for laser measurement, the longer it means that it is easier to perceive weak spatial fluctuations, and the greater the requirements for the whole system.

The Liupanshui Observatory has an arm length of only 1,200 meters, which is only slightly better than the GEO at the bottom, but thanks to the base's advanced laser technology, it is possible to detect gravitational waves in the microhertz to millihertz range under extreme conditions by using a multi-reflection scheme to improve sensitivity.

Gravitational waves are usually divided into ultra-low frequency, low frequency, medium frequency, high frequency, and ultra-high frequency, and the reasons for the occurrence are different at different frequencies.

Ultra-low and ultra-high frequency gravitational waves are extremely difficult to detect, and only in the future, the "Tianqin", which operates in space-based mode, may find that it is too difficult for the terrestrial environment to continue to improve.

Lu Qun was not in a hurry, he was now concentrating on debugging the Liupanshui Observatory with his team and the Gravitational Wave Association of the Astronomical Society.

Gravitational-wave observatories are not ready to use, and like any other large facility, they require a long period of time to be calibrated and adjusted, ranging from a few months to a year or a few years.

By the time the Liupanshui Observatory began to listen to the sound of the universe, the first "Lyra" satellite should have almost lifted off.

"Hoo ......"

It was already half past twenty-one in the evening, and the road group with another night shift stretched out, and then began to drive people without mercy:

"It's all gone, it's all gone, the body is the most important, come back tomorrow!"

Hundreds of other scholars and staff members began to pack their things one after another, and as the lights were turned off one after another, the interior of the observatory quickly darkened.

Lu Qun walked out of the door with the crowd, and his mobile phone suddenly rang just as he was looking for a car.

Ye Changsi? How could he call so late?

"Hello? I ......"

Before he could finish speaking, Ye Changsi's emotionless serious voice sounded on the other side:

"I'm Ye Changsi, Lu Qun, are you still at the Liupanshui Observatory?"

"Yes, just came out."

"Okay, you can find no more than 5 reliable people to fly over now, there is a C810 that is about to arrive at Yuezhao Airport, come over immediately, something!"

Realizing that it was unusual, Lu Qun did not continue to ask on the phone, but immediately followed Ye Changsi's words and hurriedly found a few assistants and trusted scholars who had not gone far, and went straight to the nearest Yuezhao Airport.

Just an hour later, the C810 carrying them landed on the runway at the base.

The road group that came in a hurry felt the cool breeze of the night, and couldn't help but touch the skin with large pimples.

……

More than two hours ago.

At the time of the detonation of Robin Hood, there were exactly seven satellites in the sky above it, six of which were small cube GPS satellites and the other was the "Laurel 03" exploration satellite.

The camera of Laurel 03 was firmly locked onto the heart of the explosion, capturing the spectacular scene after the nuclear explosion.

With the mine as the center, the impact of the nuclear bomb shook up the loose surface of the lunar soil for tens of kilometers around, forming a wave that was visible to the naked eye and spread outward.

Countless moon dust moon rocks directly reached the orbital velocity under the huge acceleration and were ejected, and the high moon dust formed a super dust mass dozens of times larger than the scale of the earth, but the density was much smaller and not as thick as the explosion in the atmosphere.

Soft X-rays and strong electromagnetic pulses arrive at high altitudes before moon dust.

The thermal radiation expressed in the form of soft X-rays was greatly weakened after tens of kilometers, but the violent electromagnetic pulse had a range of thousands of kilometers in the vacuum, and the signal of Laurel 03 was immediately interrupted.

Even the electronic components with a ternary as the core could not be intact in the equivalent of an EMP attack, and the fragile silicon carbide grille was easily broken down, directly destroying the satellite with significant credit.

Not to mention the other cube satellites and microsatellites, which were even exposed to soft X-rays because they were so close that their surfaces were heated and melted, leaving no corpses intact.

But fortunately, Yuegui 03 was prepared in advance, and transmitted the recorded image data to the "Queqiao-2" satellite at the Lagrange point of the moon and the earth, and then the latter avoided the first 15 minutes of electromagnetic storm and transmitted it back to Earth.

The impact of nuclear bombs on communications is comprehensive, in fact, the entire moon and its surroundings are completely shielded from communications within a radius of thousands of kilometers, but those on the back side are only less affected.

The images of the nuclear explosion seen on the ground were first sent to the Yushu base through a long anti-shielded cable, and then relayed through other satellites, and the system, which carefully avoided the impact of the nuclear bomb, was forced to interrupt after only 12 seconds of images.

It took a full 15 minutes for the moon to regain some contact with the ground, and the icons of the spacecraft lit up again.

At the United Mining Headquarters, the communication of the Wutu space station was the first to be restored, followed by "Queqiao", "Yuegui 01", "Yushu Base", etc., most of the spacecraft that took refuge on the other side in advance were intact, and almost all the satellites on the blast side were killed.

Regardless of how to make up for these losses, there is no doubt that the lethality of hydrogen bombs in space is undoubted, and even as EMP electromagnetic pulse bombs, they are quite valuable, and ordinary spacecraft cannot withstand a strong impact at all.

As for the destructive effect of the explosion on the ground, it is necessary to wait for the surviving spacecraft to move over the blast area before it can be transmitted back.

(End of chapter)