I ask you to build tractors, but you build rockets?

Liupanshui, Laser Interferometer Gravitational Wave Observatory.

There are currently 4 countries in the world with 6 gravitational wave observatories.

Aramco has two observatories (LHO) in Washington state with arms lengths of 4 kilometers and 2 kilometers respectively, and one observatory (LLO) in Washington state with arms lengths of 4 kilometers.

They are all part of the LIGO detection system and are the most advanced and sensitive gravitational wave detection devices to date. They have been undergoing upgrades. So far, the laser power has been increased by 20 times, and the sensitivity is 10 times higher than the original version.

Then there is the VIRGIN (Virgo) observatory in Pisa, Italy. Its arms are 3 kilometers long. It officially joined the LIGO system in August last year to jointly detect gravitational waves. Its sensitivity is also equivalent to the three Aramco observatories.

Finally, there is the GEO600 Observatory in Germany. Its arms are only 600 meters long. Although it was put into operation in 2002, it has low sensitivity and frequent failures, and its scientific value is extremely limited.

In addition to them, the island country activated the TAMA300 gravitational wave detector in 2000, but it was deactivated after LIGO detected gravitational waves in 2015 and transformed into a test bed for other purposes.

The island government also launched a construction plan for the Kamiokande Gravitational Wave Detector (KAGRA) in 2010, but it has not yet been completed and is expected to be put into use in 2020.

There are many indicators that define the performance of the Laser Interferometer Gravitational Wave Observatory, but the most obvious one is the length of the arms, which is the length of the interference arm measured by the laser. The longer it is, the easier it is to detect weak spatial fluctuations, and the requirements for the entire system are also higher. The bigger.

The arm length of Liupanshui Observatory is only 1,200 meters, which is only slightly better than the bottom GEO. However, thanks to the base's superb laser technology and the use of multiple reflection schemes to improve sensitivity, it is possible to detect microhertz to millihertz levels in extreme cases. Gravitational waves.

Gravitational waves are usually divided into ultra-low frequency, low frequency, medium frequency, high frequency and ultra-high frequency. The reasons for their generation vary with the frequency. At present, the gravitational wave events detected by humans are only limited to low frequency and medium frequency.

Ultra-low and ultra-high frequency gravitational waves are extremely difficult to detect. Only by finding a new way in the future, "Tianqin" operating in space-based mode may find that it is too difficult to continue to improve the ground environment.

Lu Qun is not in a hurry. He is now concentrating on debugging the Liupanshui Observatory with his team and people from the Gravitational Wave Association of the Astronomical Society.

The gravitational wave observatory is not ready for use after it is built. Like other large facilities, it requires continuous calibration and debugging for a long time, which can range from a few months to a year, or even a few years.

By the time the Liupanshui Observatory starts listening to the sounds of the universe, the first "Lian" satellite should have almost launched.

"call……"

It was already 21:30 in the evening, and Lu Qun, who had joined another late shift, stretched himself, and then began to drive people away mercilessly:

"Everyone is gone, everything is gone. Your health is the most important thing. Come back tomorrow!"

Hundreds of other scholars and staff also began to pack their things one after another. As the lights were turned off one after another, the interior of the observatory quickly became dark.

Lu Qun followed the crowd out of the door, and when he was looking for a car, his cell phone suddenly rang.

Ye Changsi? Why is he calling so late?

"feed me……"

Before he could finish his words, Ye Changsi's serious and emotionless voice sounded from the other side:

"I am Ye Changsi, Lu Qun, are you still at Liupanshui Observatory?"

"Here, he just came out."

"Okay, you can find no more than 5 reliable people to fly over now. A C810 is coming to Yuezhao Airport soon. Come over right away. Something's happened!"

Realizing that something was unusual, Lu Qun did not continue to ask on the phone, but immediately followed Ye Changsi's instructions 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 of the base.

The hurried Lu Qun felt the cool night breeze and couldn't help but touch the skin with large pimples.

…

More than two hours ago.

When Robin Hood detonated, there were seven satellites just above it, six of which were cube-shaped GPS satellites with very small masses, and the other one was the Laurel 03 exploration satellite.

The camera of Laurel 03 was firmly locked on the center of the explosion and captured the spectacular scene after the nuclear explosion.

With the mine as the center, the impact of the nuclear bomb shook up the loose lunar soil within dozens of kilometers around it, forming a wave that spread outwards visible to the naked eye.

Countless lunar dust and lunar rocks directly reached the orbital speed under the huge acceleration and were ejected. The high lunar dust formed a super dust cluster dozens of times larger than that on the earth, but it was much smaller in density. The thickness of the atmosphere exploded.

What reaches high altitudes before lunar dust is soft X-rays and strong electromagnetic pulses.

Thermal radiation expressed in the form of soft X-rays is greatly weakened after tens of kilometers, but the violent electromagnetic pulse has an influence range of thousands of kilometers in the vacuum, and the signal of Laurel 03 was immediately interrupted.

Even the electronic components with ternary as the core could not survive the equivalent of an EMP attack. The fragile silicon carbide grid was easily penetrated, directly destroying this remarkable satellite.

Not to mention other cube satellites and micro-satellites, they were even attacked by soft X-rays because they were too close, and their surfaces were heated and melted, and not even their intact bodies were left.

But fortunately, Yuegui 03 was prepared in advance and transmitted the recorded image data to the "Queqiao 2" satellite at the Moon-Earth Lagrange point at any time. The latter then transmitted it back after avoiding the initial 15-minute electromagnetic storm. Earth.

The impact of nuclear bombs on communications is comprehensive. In fact, the entire moon and communications with a radius of thousands of kilometers around it are completely blocked, but the impact on the back is smaller.

The images of nuclear explosions seen on the ground were first sent to the Yushu base through long anti-shielding cables, and then forwarded through other satellites. This system, which carefully avoided the impact of nuclear bombs, only sent back 12 seconds of images. Forced to interrupt.

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

At the United Mining Headquarters, communications at the Wutu Space Station were restored first, followed by "Queqiao", "Yuegui 01", "Yushu Base", etc. Most of the spacecraft that had taken refuge on the other side in advance were intact, while those on the explosion side were intact. Almost all of those satellites were killed.

Regardless of how these losses are to be compensated, there is no doubt that the lethality of hydrogen bombs in space is unquestionable. Even as an EMP electromagnetic pulse bomb, it is of considerable value. Generally, spacecraft cannot withstand the strong impact.

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