1 . Extremely energetic light from space is an unexplained wonder. Scientists don’t know where that light comes from, exactly. And now astronomers have spotted this light, called gamma (伽马) rays, at higher energies than ever before.
You can’t see gamma rays with your naked eyes (肉眼). They are much more energetic than the light that we can see. So you need a fancy detector to spot them. The Large High Altitude Air Shower Observatory, LHAASO, is an experiment in China. It searches for extremely high energy gamma rays.
Scientists have spotted 12 gamma-ray hot spots. These are parts of the sky from which the gamma rays are sent out. Those hot spots show that our galaxy (银河系), the Milky Way, has powerful particle accelerators (粒子加速器). But those particle accelerators aren’t made by humans. Instead, they come from violent events in the universe. They might be exploding stars, for example. Such violent events make electric and magnetic fields, which can speed up protons (质子) and electrons. Those fast particles can then produce gamma rays with a lot of energy. That can happen when protons interact with other matter in space, for example.
Scientists aren’t sure what could produce gamma rays with the extreme energies observed. But the new observations point to two possibilities. One hot spot was associated with the Crab Nebula. That’s the remains of an exploded star. Another possible source was the Cygnus Cocoon. That’s a region where massive stars are forming. The stars send out strong winds in the process.
LHAASO is located on Haizi Mountain in China’s Sichuan province. It is not yet fully operational. It’s due to be completed later this year. Then, it could find even more gamma rays.
1. What can we learn about gamma rays?| A．They are invisible to our naked eyes. | B．They are often ignored. |
| C．They contain little energy. | D．They can be explained. |
| A．To make the explanation lively. |
| B．To help understand the Milky Way. |
| C．To show the universe is expanding. |
| D．To show how gamma rays might be produced. |
| A．Disappointing. | B．Exciting. | C．Accurate. | D．Uncertain. |
| A．There will be more gamma rays. |
| B．The universe is exploding with great energy. |
| C．Astronomers have spotted gamma rays with higher energy. |
| D．Gamma rays can only be seen by astronauts. |
