Can you list a few internationally renowned underwater robots and their landmark missions?

Certainly, there are many cool stories in this field. When we talk about underwater robots, just like discussing rockets and probes for space exploration, each has its own legendary journey. Let me give you a few examples that even ordinary people might be familiar with:

1. Alvin - The Pioneer of Deep-Sea Exploration

You can imagine the 'Alvin' as a small 'bus' capable of carrying three people (one pilot and two scientists) into the deep sea. Although it's a manned submersible, its equipped robotic arms made it a pioneer in underwater robotics technology, inspiring many subsequent robots.

• Iconic Missions:
  • Retrieving a Hydrogen Bomb (1966): This was one of its early claims to fame. A U.S. B-52 bomber collided with a refueling aircraft over the Mediterranean Sea, dropping a hydrogen bomb. Finding a bomb in the vast ocean was no easy feat. Alvin was dispatched, and after more than two months of searching, it finally located and successfully recovered the hydrogen bomb from nearly 800 meters deep. This incident sounds like something straight out of a Hollywood movie.
  • Discovering the Titanic (1986): This is its most widely known mission. Alvin descended to nearly 4,000 meters deep, conducting the first manned exploration of the Titanic wreck. It brought back world-shaking photos and videos, allowing us to see the long-slumbering giant ship with our own eyes for the first time.
  • Discovering Deep-Sea Hydrothermal Vents (1977): The scientific significance of this mission even surpasses that of finding the Titanic. In the East Pacific Ocean, it discovered 'black smokers' (hydrothermal vents) on the seabed and found thriving communities of organisms that survive entirely on chemical substances, independent of sunlight. This discovery directly rewrote biology textbooks, revealing completely different forms of life on Earth.

2. Jason - The 'Archaeologist' of Precision Operations

If Alvin was an explorer, then Jason is a 'subsea archaeologist' or 'engineer' specializing in precise operations. It is a Remotely Operated Vehicle (ROV), connected to a mother ship by a long cable and controlled in real-time by personnel on board. Its robotic arms are highly flexible, and its cameras are high-definition.

• Iconic Missions:
  • Detailed Exploration of the Titanic: After Alvin, Jason also visited the Titanic multiple times. However, its missions were more detailed, such as using high-definition cameras to 'fly' inside the ship's hull, meticulously filming the ship's dining rooms, staircases, and cabins, allowing us to experience the interior of the wreck as if we were there.
  • Mediterranean Shipwreck Research: Jason has been widely used for archaeological research of ancient shipwrecks. Thousands of meters deep, its nimble robotic arms can carefully retrieve artifacts such as ancient Roman pottery and coins, making significant contributions to humanity's study of ancient maritime history and trade.

3. Nereus - Conqueror of the Mariana Trench

Nereus was a technologically unique vehicle. It was a 'hybrid' robot, capable of both real-time remote control via a thin fiber-optic cable, much like Jason, and disconnecting from the cable to autonomously navigate and explore like a true Autonomous Underwater Vehicle (AUV).

• Iconic Missions:
  • Diving into the Challenger Deep (2009): This was its most shining moment. Nereus successfully descended to the deepest part of Earth's oceans – the Challenger Deep in the Mariana Trench, reaching a depth of nearly 11,000 meters. Before it, only two humans (aboard the Trieste) and one Japanese unmanned probe had reached that depth. It not only successfully arrived but also conducted hours of exploration and sampling, transmitting back invaluable visual data. This achievement showcased humanity's top technological prowess in exploring extreme environments. (Sadly, Nereus was lost during a mission in 2014, remaining forever in the deep sea.)

These robots are like emissaries sent by humanity to another world. They replace our eyes and hands, exploring those dark, high-pressure, cold, unknown waters, and each time they bring back discoveries that challenge our imagination.