Life on the International Space Station(ISS)——the place where astronauts dwell(居住) in space-differs from that on Earth. For example, astronauts have to rely on the ISS’ life support system, which provides oxygen and absorbs carbon dioxide. But sometimes astronauts need to deal with unusual air leaks.
Normally, the ISS releases a small amount of air each day to rid the harmful gases. But recently, the air seemed to be leaking at a slightly higher rate than usual, which became a cause for concern, according to MSN. The three crew members currently on board are staying in the Russian segment(舱段) of the ISS temporarily while NASA tries to find the origin of the leak in the US segment.
This isn’t the first time that an air leak has occurred on the ISS. On Aug 29, 2018, an air leak was discovered on the ISS. Fortunately, six people on board found a hole measuring 2 millimeters in diameter on Soyuz MS-09, a Russian spacecraft temporarily docked with the ISS. The astronauts patched the hole with tape. But the question remains： What can cause holes in the hard surface of spacecrafts? Space debris(碎片) can.
In low orbit, space debris circles around Earth at speeds between 7 to 8 kilometers per second. Because of the high speed, it can penetrate the surface of the ISS. A NASA report submitted to the US Congress said the ISS has a 55-percent chance of being penetrated by some sort of space debris, according to the website New Scientist. However， finding a tiny hole is not easy.
The ISS measures some 109 meters by about 73 meters, roughly the size of a soccer field. So how do astronauts find a tiny hole in such a large area?
When air leaks occur, astronauts seal off various sections of the ISS to narrow down the area. Once the location of the leak is found, it is closed and the pressure on each side is checked.
This is exactly what NASA is doing now. The US space agency has been trying to find the hole, which is equivalent to “finding pinholes in a large airliner”, Xinhua News Agency noted.
【小题1】What can we know about the recent air leak?| A．It has exposed astronauts to harmful gases. |
| B．More gas than usual is leaking in the ISS. |
| C．It is happening in the Russian segment. |
| D．NASA has already found the origin of the leak. |
| A．It was due to the docking of spacecrafts. |
| B．The hole was found on the surface of the ISS. |
| C．It was repaired with tape by crew members. |
| D．Space debris was found in the spacecraft. |
| A．What causes space debris. |
| B．What the surface of the ISS is like. |
| C．Why space debris can cause air leaks. |
| D．How to find holes made by space debris. |
| A．finding the origin of the leak |
| B．closing various segments of the ISS |
| C．patching the hole with tape |
| D．checking the pressure of the sections |
