Hong Kong’s Beijing Tianbing space company launched a rocket by accident on Sunday while testing its first-stage power system.

The company, which is also known as Space Pioneer, tried to test the first stage of the Tianlong-3 rocket by firing it up. However, because of a structural flaw, the rocket was sent into space, where it was destroyed.

“The engine thrust reached 820 tons during the test run,” the company said in a statement. “The first-stage rocket ignited normally.” “Due to structural failure at the connection between the rocket body and the test bench, the first-stage rocket separated from the launch pad.”

Soon after the rocket took off without warning, the computer on board turned off by itself. The rocket was seen flying straight up for a short time before turning horizontal and falling back to the ground.

Wow. This is apparently what was supposed to be a STATIC FIRE TEST today of a Tianlong-3 first stage by China's Space Pioneer. That's catastrophic, not static. Firm was targeting an orbital launch in the coming months. https://t.co/BY9MgJeE7A pic.twitter.com/L6ronwLW1N

— Andrew Jones (@AJ_FI) June 30, 2024

The rocket went into the mountains about 0.9 miles (1.5 km) from where it was launched in Gongyi City, Henan Province, China. According to the company, there have been no reported injuries, and all personnel had been evacuated from the area before the launch.

Another view here. Got to hope that there are no casualties. This is absolutely wild. And Space Pioneer has already reached orbit with Tianlong-2, so this is just staggering. https://t.co/QlQT13FNtI pic.twitter.com/F58tJhVoRJ

— Andrew Jones (@AJ_FI) June 30, 2024

It’s not often that something like this happens in space history. Harvard University astrophysicist Brad Tucker told the New York Times that the last time something similar happened was in 1952, when NASA’s Viking 8 broke free of its anchors and landed 8 kilometers (5 miles) away in the desert.

The Tianlong-3 rocket is meant to be used more than once so that the very high cost of space travel can be cut down. The newest version should be able to send up to 17 tons into low-Earth orbit or 14 tons into an orbit around the sun. Beijing Tianbing says the unintended flight was the most powerful system test of any test done in China, though the debris on the nearby hills shows it wasn’t exactly a resounding success.

Every day, thousands of people take the Tube from the north to the south of London or the Channel Tunnel to cross the English Channel. These routes are only possible because of something very important: tunnels that are underwater. But how does someone build something so amazing?

The shield for tunneling
Before French-British engineer Marc Isambard Brunel got an idea from nature in 1818, no one knew how to build an underwater tunnel. After seeing how the shell plates of a shipworm let it cut through wood, Brunel took that idea and made the tunneling shield bigger.

In this case, it was a huge, rectangular mold made of cast iron. The walls had shutter openings that were opened one at a time so that miners could dig into the soft ground outside. The shield was then moved forward with screw jacks, and the process started all over again. In the newly carved area behind, a protective “shell” of bricks was built around the tunnel.

Because of this, the first tunnel under the water was built under the River Thames in London. It was finished in 1842. In later tunnels under the Thames, the air in front of the shield was pressed down to try to stop flooding while the tunnels were being built.

Today, tunneling shields are still used. They are round and usually made of steel, which is also used to make the support rings for the tunnel. Modern versions also use hydraulic jacks to move the shield forward. There is a door in front of the shield that can be used when it’s not moving. Shields also have a protective hood on them for the people who go out to work there.

Machines that dig tunnels
Of course, digging through soft ground is one thing, but boring through rock under the water is something completely different. In this case, tunnel boring machines (TBMs), which were used to build the Channel Tunnel, changed the rules of the game dramatically.

The tunneling shield and the TMB both do the same thing, but the TMB uses a mechanical spinning cutting head to dig through the rock in front of it instead of people. It does this by putting stress on the rock, which breaks it up. There is no need for people to move the broken rock out of the way because it is taken back on a conveyor belt.

There are eleven TMBs that were used to dig the three 56.3-kilometer (35-mile) long tunnels. Some parts of the tunnels are 45 meters (148 feet) below the surface of the water.

Tunnels with immersed tubes
In the first two methods, the tunnel walls are built as the work is done, but there is another way to do it. Immersed tube tunneling is another method. W.J. Wilgus, an American engineer, was the one who created it.

With this method, the tunnel is built somewhere else first, with several sections already built, while a trench is dug into the riverbed or seabed where the tunnel will go. The pieces are then floated to the spot and sunk into place. The water is then drained from them, and dirt from the excavation is put on top of the tunnel to bury it and make the bed level again.

People have been interested in the Antikythera mechanism for more than 120 years, and new research has shed more light on this amazing machine in recent years. The pieces that are still there show that it was probably used to figure out things like eclipses and where the planets were in the sky. With some statistical methods that are often used in gravitational wave research, astronomers from the University of Glasgow have found more proof that it is linked to the Moon.

Professor Graham Woan and Dr. Joseph Bayley each used a different method after an interesting X-ray analysis of the object was done years ago. Some people don’t know how many holes are in one of the rings, which is thought to be a calendar. There is only a small piece of the ring left, and it’s hard to say for sure what it is because it spent 2,000 years underwater.

Based on the X-ray data, Woan and Bayley used bayesian statistics to determine how many holes there were in the rings. The most likely number was either 354 or 355 holes, they found. Around 354 days make up a lunar calendar. Based on the research, this number is 100 times more likely than 360 holes, which is what the Egyptian solar calendar has. This means that a 365-hole ring, which would be like a real solar year, is very unlikely.

“Towards the end of last year, a colleague showed me data that YouTuber Chris Budiselic had collected. Budiselic was trying to make a copy of the calendar ring and was looking into ways to find out how many holes it had,” Professor Woan said in a statement. “I thought it was an interesting problem that I might be able to solve in a new way over the Christmas break, so I started using some statistical methods to find the answer.”

The Markov Chain Monte Carlo and nested sampling methods were used. These are common ways to figure out how likely one result is given incomplete data. These techniques lead us to believe that the whole ring was 77.1 millimeters across and had either 354 or 355 holes spaced 0.028 millimeters apart.

“Previous research had suggested that the calendar ring probably followed the lunar calendar, but the two methods we used in this project make it much more likely that this was the case,” Dr. Bayley said. “It’s made me appreciate the Antikythera mechanism and the work and care that Greek craftsmen put into making it even more. To punch the holes so precisely, they would have needed to be measured very accurately and punched with a very steady hand.”

The study has been written up in The Horological Journal.