2 . If Mars were the popular kid in school, Venus (金星) would be the unwelcome one sitting in the corner, largely ignored. Venus has nearly the same mass and size as Earth, but being closer to the sun, it gets nearly twice as much heat from the sun.

However, instead of having a climate that is just a warmer version of Earth’s, Venus’s surface and atmosphere are unbearable: clouds of sulphuric acid (硫酸) blanket the planet, while at ground level, it is hot enough to melt lead. Despite this, there is now a sign that Venus may harbour life. Jane Greaves at Cardiff University, UK, and her colleagues recently detected (发现) phosphine (磷化氢) in Venus’s atmosphere, with one potential explanation that it is the by-product of biology. That is because the only way this gas is made on Earth is in laboratories or by microbes (微生物). Though this doesn’t mean it was produced by life on Venus, attempts to find non-biological explanations for its presence have so far failed. Our best way of confirming or rejecting the possibility of life on Venus is to go and have a proper look. While Mars has been the focus of interplanetary (行星间的) exploration efforts lately, the phosphine discovery lets people look at Venus in a new light. As NASA administrator Jim Bridenstine tweeted: “It’s time to prioritize Venus.”

In the months and years to come, computer simulations(模拟) will be used to further study the possible chemistries of the atmosphere on Venus. More laboratory experiments will be conducted to try to identify other ways the phosphine there could be produced. However, there is no guarantee that these efforts will reveal the true nature of this substance on Venus. A newly-proposed strategy is to directly sample the atmosphere and surface of Venus. By doing so, we would be able to take direct measurements of phosphine.

The discovery of phosphine in Venus’s atmosphere is a great accomplishment. The scientific efforts may be just what we need to finally refocus on this neglected world. Possibly, the quiet kid in the corner may get the last laugh

Black holes aren't actually holes. They are     1    ( object) that contain a lot of mass packed into a tiny area. Most black holes form when giant stars die and break down. As     2     star dies, the material that it' s made     3     gets squeezed into a smaller and smaller space. Eventually it forms     4     is called a stellar (恒星)mass black hole. Astronomers estimate that one of these relatively small black holes     5    (be) born every second.

Supermassive black holes are much     6    ( big), as their name suggests. Instead of containing the mass of one star, they can contain the mass of millions or billions of stars.

Scientists first picked up signs of black holes in the late 1700s. But no one had actually seen one until     7    (recent). Because light can't leave a black hole, it's not possible to see one with a regular telescope. But many black holes are surrounded by a swirling ring of gas and other material. This ring,     8    (call) an accretion disk (吸积盘)，heats up and gives off light. Scientists can study that light to learn about black holes.

In early 2019, scientists     9    (share) the first picture of a black hole. They made this picture     10     (use) a virtual telescope that combined the powers of eight observatories around the world.

6 . Do you think alien beings exist somewhere in the universe? It seems like Mars, our closest neighbor, has inspired the most science fiction as the place where aliens are most likely to come from. Recent Mars probes (探测) have shown us that there is no life on that planet—at least not now. But that does not mean that life does not exist elsewhere—after all, the universe is really big. A lot of scientific research is going on in the search for “extraterrestrial life”.

Think about it—why should the seven billion people on this little planet be the only living beings in the universe? It would, in fact, seem logical that this is not the case. So scientific research in this matter is based around the idea of finding other planets that have environments that can support life —environments similar to the Earth. The search is on for the evidence of the existence, or earlier existence of life: from very wise beings to simple organisms (有机物).

So far, there have been a number of theories as to which planetary bodies may have an atmosphere that can support such life and therefore deserve closer attention. As for places within our own Milky Way Galaxy, it has been assumed over the decades that Mars and Venus, as well as some of the moons of Jupiter and Saturn, may have been hosts for life. Now, as technologies have improved and we can obtain measurements of the composition of the atmosphere on extra-solar planets, the chances of finding “alien” life forms are increasing.

There has been a theory that some of the planets in the habitable zone of the red dwarf star Gliese 581 may be able to support life. In 2007, scientists discovered exoplanet Gliese 581c—and felt that its atmosphere was most suitable for supporting life. But further research revealed that it would not. Now, attention has been turned to Gliese 581d, at the outer edge of the star’s habitable zone. The main standards for deciding whether a planetary body can be life-supporting are atmospheric conditions which allow the existence of water. Gliese 581 is about 20. 4 light years away from the Earth, so even if life does exist there, the distance would mean that communication would be unlikely.

Having said this—who says alien life forms (if they exist) need water?

7 . Scientists who study the Sun watch for sunspots—violent storms that can affect communications，navigation systems and even electric power stations on the Earth.

Sunspots are a product of huge electromagnetic storms on the Sun. Scientists on the Earth are able to observe sunspots eight minutes after they happen. That is how long it takes for the Sun’s light to reach us.

The first electrically charged particles (颗粒）from a sunspot enter the Earth’s atmosphere about 20 to 30 minutes after the storm happens. These particles can harm human beings. So before they arrive, astronauts on the International Space Station move into special areas designed to protect them from their effects.

About a day or two later, the biggest part of the storm arrives. It is called a coronal mass ejection. “That is billions of tons of solar material that's blown away from the Sun. It’s traveling millions of kilometers an hour, but that is relatively slow.” says Alex Young, the Associate Director for Science at NASA's Heliophysics Science Division.

Several civilian government agencies and the U.S. Air Force watch weather conditions in space 24 hours a day. NASA does so because it must protect its astronauts and the electronic devices on its spacecraft.

Scientists are also trying to understand why the number of sunspots rises and falls at almost regular intervals every 11 years. In other words, scientists can almost predict the amount of solar activity. Sometimes the intensity (强度）is higher，sometimes lower，For example, the current solar cycle, as it is called, is much lower than the previous one.

Several satellites watch the Sun and the environment between the Sun and tho Earth. Pictures and other information from the satellites tell scientists what is happening on and near the Sun.

Alex Young says we have only been looking at the Sun with powerful instruments for about 30 to 40 years. Thai is a very short time compared to ll\o four billion years that tho star has been shining.