“The bigger the waves, the more fish there are”? However, the danger is even greater! 丨 Expo Daily

“The bigger the wind and waves, the more fish there are”?

But the danger is even greater!

Don't eat oysters on the beach after the typhoon! Industry insiders speculate that these oysters blown to the beach by the typhoon may be artificially cultivated in the surrounding waters. Oysters grow on rocks and will not fall off easily. When the typhoon comes, the oysters fall into the sea due to the southwest wind and waves.

There is mud and sand in the sea. Oysters that fall into the mud are basically dead, while those that fall into the sand "survive" and are washed onto the beach by the waves.

These oysters washed up on the shore have been soaked in seawater for a long time, and their freshness can no longer be guaranteed. In addition, these oysters may also carry a large amount of pollutants and harmful substances, so try not to eat them.

Moreover, after a typhoon, some dangerous marine creatures may appear in the nearshore waters, such as jellyfish, sea urchins and sea snakes, whose venom may cause serious harm to the human body or even threaten life.

The passing of a typhoon does not mean that the danger is completely eliminated. The seaside is windy and rough, so you should pay special attention to secondary disasters, such as geological crises in areas prone to geological disasters and bacterial contamination in flooded areas. You should not take it lightly.

Moon: Dying and sick, sitting up in shock,

It turned out to be me who pretended to be dead!

The evidence for determining whether a planet is "dead" or not is whether there is still large-scale magma activity on the planet.

Before the Chang'e-5 mission, humans had obtained lunar samples nine times, and together with lunar meteorites collected on Earth, the rock ages measured by these lunar samples were basically greater than 3 billion years. Therefore, the early understanding of the scientific community was that the moon's magma activity stopped about 3 billion years ago.

The precise dating results of basalt fragments in the Chang'e-5 lunar soil samples have refreshed this understanding, showing that there was still large-scale magma activity on the moon about 2 billion years ago.

A research team from the Institute of Geology and Geophysics, Chinese Academy of Sciences, changed their thinking and found that the products of volcanic activity include not only rocks but also volcanic debris, including volcanic glass beads.

The team selected about 3,000 glass beads from about 3 grams of Chang'e-5 lunar soil and conducted detailed research. They screened out three volcanic glass beads through scanning electron microscopy, electron probe, ion probe and other methods, and further carried out precise dating through uranium-lead isotope system measurements. The conclusion was unexpected that these volcanic glass beads were formed about 120 million years ago.

Diagram of the formation pattern of volcanic glass beads (Drawing: Zhang Ting and Wang Yu from Universal Museum Bookstore)

Image source: Institute of Geology and Geophysics, Chinese Academy of Sciences

Why do we say “Every autumn rain brings a chill”?

There is a proverb that goes, "One autumn rain brings one chill." This is a valuable experience drawn by the ancients through years of observation. This means that the temperature will gradually drop after entering autumn, and each autumn rain will bring more chill.

After the summer solstice, the sun's direct point gradually moves southward toward the Tropic of Capricorn, and the sun's rays to the northern hemisphere continue to tilt. At this time, the intensity of solar radiation weakens and the number of daylight hours decreases. This not only causes the ground to receive less and less heat, but also intensifies the ground's own radiation cooling, gradually moving towards a state where heat input is insufficient to meet output.

Moreover, the higher the latitude, the more obvious the shortage of heat. Therefore, the thicker the cold air accumulates in high latitudes, the more frequent the southward movement of cold air masses, and the southward movement of cold air masses becomes inevitable. This is the most fundamental reason for the cold weather after each autumn rain.

After entering autumn, a cold air mass moves southward from Siberia and Mongolia and encounters warm and humid air from the south. The interface between the cold and warm air masses clashes and interacts, resulting in rainfall. During the day, clouds block the sunlight and "cold rain" falls from high altitude, causing a more drastic drop in temperature.

The cooling caused by rain is only an appearance. Cold advection plus strong radiation cooling from the ground are the main reasons why people feel that the air near the ground becomes colder with each autumn rain.

After the battle between warm air and cold air, the latter will usually lose and slowly retreat to the south. Then, the local area will be controlled by the cold air mass, the weather will clear up, and the temperature will drop. A few days later, when new cold air moves south from Siberia or Mongolia and meets the increasingly weak warm and humid air again over the local area, new rainfall and cooling weather will occur.

Image source: pixabay

New discoveries from the wreck of the Titanic

On April 15, 1912, the Titanic was on its way from Southampton, England to New York when a tragedy occurred. The ship sank after hitting an iceberg, killing more than 1,500 passengers and crew members on board.

For many years, the exact location of the luxury liner sank remained a mystery until an expedition led by Robert Ballard confirmed the location of the luxury liner in 1985. Since then, many explorers, experts and tourists have made the dangerous journey back to the wreck to document this historical archaeological site.

Today, the ship has been sleeping on the seabed nearly 4,000 meters deep in the cold North Atlantic for 112 years.

In 1994, a U.S. federal court awarded the sole "salvage custody" of the Titanic to RMS Titanic, Inc., designating it as the only organization permitted to legally salvage artifacts from the wreck. The organization and its affiliates have led eight expeditions so far, and recently released high-definition images taken during the latest expedition.

Using lidar, sonar, and a supermagnetometer (a device used to lock onto metal objects), they were able to create a detailed map of the ship and its wreckage. It was with these tools that the explorers were able to find an artifact that was thought to have been lost—a 2-foot-tall bronze statue known as Diana of Versailles (Figure 1).

According to researchers, Diana of Versailles is the centerpiece sculpture in the first-class passenger lounge and is widely considered to be the most beautiful and exquisite artwork on board.

But unfortunately, the Titanic broke in two during the sinking, and the lounge was torn apart. In the chaos and destruction, Diana of Versailles fell into the dark debris.

The new expedition also found that the iconic railing on the bow had fallen off and was damaged. Readers who have seen the movie "Titanic" should still remember the scene where Leonardo DiCaprio shouted "I am the king of the world" on the bow. This scene perfectly reproduces the real scene on the Titanic (Figure 2).

New images taken during the expedition also show that the port bow portion of this railing has peeled off (Figure 3). Based on the comparison results, the researchers believe that the damage occurred in 2022.

"Given the harsh ocean conditions and the destructive power of metal-eating bacteria, most of the Titanic's wreckage will likely rot within decades. The discovery of the Diana statue is an exciting moment. But we are saddened by the disappearance of the iconic bow railing and other evidence of decay. This will strengthen our determination to salvage and protect these artifacts," the expedition team said in the announcement.

Figure 1 The Diana statue from Versailles discovered this time

Image source: https://expedition.discovertitanic.com/

Figure 2 Classic scene from the movie Titanic

Image source: m1905.cn

Figure 3 The railing of the Titanic wreckage has been damaged

Image source: https://expedition.discovertitanic.com/

The content is compiled from China Science Popularization Expo Weibo, Guangzhou Daily, China National Radio, People's Daily Health Client, Institute of Geology and Geophysics, Chinese Academy of Sciences, Digital Beijing Science Center, Science Academy, CCTV Documentary Weibo

This article was first published in China Science Expo (kepubolan)

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