1. Why Ships Use Special Names for Right and Left
On a ship, the right and left sides have special names. In Japanese, they are called "ugen" and "sagen." In English, the ship’s right side is called "starboard" and its left side is called "port." [1]
Why are they called that? It comes from old ships. Long ago, the steering oar was attached to the right side of the ship. The old English word for steering oar was "steer-board." It is believed that this became the word "starboard." [1] Because the steering oar was on the right, the ship would dock with its left side facing the shore to unload cargo. This is believed to be the origin of calling the left side "port." [1]
2. How Red and Green Lights Show a Ship's Direction at Night
Ships have lamps called "navigation lights" that they turn on at night. The rule is strict: the left side (port) shows a red light, and the right side (starboard) shows a green light. [1]
By seeing the color of the light from another ship, you can tell which way the other ship is facing, even in a dark sea. If you see a red light, it means the other ship's left side is facing you. If you see a green light, it means the other ship's right side is facing you. [1]
3. What Ships Say to Each Other With Horn Sounds
Ships have a loud signaling device called a ship's horn. They use long blasts and short blasts to tell nearby ships, "I am going to do this next." [1]
A long blast lasts about 4 to 6 seconds. A short blast lasts about 1 second. The meaning changes depending on the number of blasts and the combination of long and short sounds. One short blast signals, "I am altering course to starboard." Two short blasts mean "I am turning the rudder to the left." [1]
4. Which Way Ships Turn When Heading Straight at Each Other
When two ships are heading straight toward each other, both ships must turn to the right. They pass each other on the left side. [1]
When two ships' paths cross at an angle, the ship that sees the other ship on its right side must move out of the way. This ship is called the "give-way vessel." The ship that sees the other ship to its left is the "stand-on vessel." It must keep its course and speed. [1]
5. How Radar and AIS Help Ships Avoid Collisions Today
Today, ships use more than just lights and horns. They also use radar and a system called "AIS." AIS stands for Automatic Identification System. It automatically exchanges information like position, speed, and destination with other ships using radio waves. [1]
With these tools, you can check the position and movement of nearby ships on a screen, even on foggy days or at night. However, even with these machines, the rules for navigation lights and horns are still used today. They remain rules that people can follow using what they see and hear., even when the machines cannot be used. [1]
Try It Yourself
If you go near a port or the sea, try watching the ships. You can look for the colors of the lights on the right and left sides. From a safe public viewing area, look for red and green lights at a port at night with an adult. [1]
You can also try to remember the words "port" and "starboard." Try saying right and left using these new names. [1]
It is helpful to write down one word you are curious about. It becomes a starting point for looking things up later. Even just asking, "Does AIS exist for planes too?" is enough. [1]
SAFETY NOTE: Watch ship lights or listen for horns only from a safe public viewing area, with an adult.