1 . Scientists know quite a lot about stars. After centuries of pointing telescopes at the night sky, astronomers and amateurs alike can figure out key traits of any star, such as its mass or its composition.
To calculate a star’s mass, just look at the time it takes to orbit a companion star. Then do a bit of calculation. To determine what it’s made of, look to the spectrum of light the star sends out. But one question scientists haven’t quite cracked yet is how to calculate the exact time of a star.
“The sun is the only star we know the age of,” says astronomer David Soderblom. He works at the Space Telescope Science Institute in Baltimore, Md. We use what we know about it and how it compares to others, he says, to figure out the age of other stars.
Even well-studied stars surprise scientists every now and then. In 2019, the red supergiant Betelgeuse became gradually dark. At the time, astronomers weren’t sure if this star was just going through a phase. The alternative was more exciting: It might be ready to explode as a supernova. (Turns out it was just a phase.) The sun also shook things up when scientists noticed that it wasn’t behaving like other middle-aged stars. It’s not as magnetically active as other stars of its age and mass. That suggests astronomers still might not fully understand the timeline of middle age.
Using physics and indirect measurements, scientists can make a rough estimate of a star’s age. Some methods, it turns out, work better for different types of stars.
Why do we even care? Galaxies are huge collections of stars of different ages. Star ages might help us figure out how such galaxies grow and evolve or how planets within them form. Knowing star ages might even assist in the search for life in other solar systems.
1. What may scientists want to research about stars most now?| A．Their companions. | B．Their types. |
| C．Their ages. | D．Their characteristics. |
| A．Discussed. | B．Described. | C．Touched. | D．Solved. |
| A．To show scientists still have puzzles about stars. |
| B．To prove scientists have studied stars to the full. |
| C．To provide facts for scientists’ researches on stars. |
| D．To warn scientists to notice some surprising stars. |
| A．The reasons for caring about the space. | B．The significance of researching star ages. |
| C．The ways of measuring a star’s age. | D．The benefits of figuring out solar systems. |
2 . A new study focuses on K2-18b, an exoplanet(系外行星) discovered in 2018, which orbits a red dwarf star close enough to receive about the same amount of radiation from its star as Earth does from our sun.
Recently, scientists have discovered gas giants that have water in their atmospheres, but this is the least giant planet ever to have water detected in its atmosphere. “The water detection was quite clear to us relatively early on,” lead author Bjorn Benneke, a professor at the Institute for Research on Exoplanets at the Universite de Montreal, told Space.com in an interview.
“Studies have suggested that planets with hydrogen-rich atmospheres could host certain forms of life.” Benneke said. However, “K2-18b’s large atmosphere is extremely thick and creates high-pressure conditions, which likely prevents life as we know it from existing on the planet’s surface.” a news release reads. While these researchers found evidence for liquid water clouds on K2-18b, because of its lack of surface, rain wouldn’t pool on the planet. Without a real surface, so to speak, landing on the planet would also be nearly impossible to land on, especially because the gas is so thick and has such an incredibly high pressure that any Earth-created spacecraft sent there would be destroyed.
Benneke suggests that, possibly, this planet formed by rock absorbing large amounts of gas, “like a vacuum cleaner,” he said. The gas absorbed would have more than doubled the planet and increased its volume Warren eightfood.
To come to these conclusions, the research team analyzed data from Hubble Space Telescope observations that they made between 2019 and 2020 of the K2-18b planet passing in front of its star eight times. This type of research, Benneke said, is leading toward a final goal of “being able to study real, true earth-like planets.” We are not quite there yet, he said, but this is really exciting.”
1. Why is it impossible to land on the K2-18b?| A．It has thin gas. | B．It doesn’t have a real surface. |
| C．It has too much water. | D．It is too far from the earth. |
| A．By releasing gas itself. | B．By receiving radiation from the sun. |
| C．By taking in much gas by rocks. | D．By getting away from the red dwarf star. |
| A．Scientists are making progress in studying real earth-like planets. |
| B．It is impossible for humans to land on other earth-like planets. |
| C．Scientists have succeeded in exploring K2-18b completely. |
| D．The K2-18b planet has passed before its star eight times between 2019 and 2020. |
| A．The exploration of the outer space. |
| B．The study of solar systems’ environment. |
| C．The discovery of the K2-18b planet. |
| D．The research on the K2-18b planet. |
1. What does the woman think is the problem living on the moon?
| A．Money. | B．Distance. | C．Technology. |
| A．A space pioneer. | B．A moon settler. | C．A shuttle designer. |
| A．It is very cool. | B．It isn’t practical. | C．It is reasonable. |
4 . It seems that we are one step closer to finding alien life and maybe a future home for humanity. Scientists from NASA have found a new solar system filled with planets that look like the Earth and could even support life.
The group of seven planets, which orbits a star called Trappist-1, is 39 light years away from the Earth in the constellation of Aquarius(水瓶座). And three of them are in the “habitable zone” - the area around a star where water is most likely to be found. This is important because water is necessary for life.
“This is an amazing planetary(行星的) system - not only because we have found so many planets, but because they are all surprisingly similar in size to the Earth”, astronomer Michael Gillon from the University of Liege in Belgium told The Independent.
Trappist-1 is a “dwarf star(矮星)” which is colder and shines dimmer than our sun. If a person were on one of the seven planets, everything would look a lot darker than usual. The amount of light heading toward our eyes would be about 200 times less than we get from the sun, according to The Independent.
Because of that, Trappist-1, together with many other dwarf stars, was never on the list of places where scientists looked for alien life. But Michael Gillon, lead researcher behind the discovery, decided to give dwarf stars a chance. He built a telescope in Chile to observe 60 of the closest dwarf stars, and it turned out that Trappist-1 was worthy of the effort.
The researchers hope that they can spend more time watching the newly found planets to learn more about them. Even though more research is needed before determining whether these planets could really support life, the discovery is still encouraging. It shows just how many Earth-size planets could be out there.
“[The discovery] gives us a hint that finding a second Earth is not just a matter of if, but when,” NASA scientist Thomas Zurbuchen told The Telegraph.
1. What can be learned about the new solar system from the text?| A．It contains a sun and planets like the Earth. |
| B．Seven planets move around Trappist-1. |
| C．Water can be found on all of the planets. |
| D．There are aliens on the planets. |
| A．The size of the planets is similar to that of the Earth. |
| B．It has the same number of planets as our solar system. |
| C．Scientists have found alien life in the new solar system. |
| D．The planets are more suitable for humans to live than the Earth. |
| A．It is impossible to find alien life on the planets of Trappist-1 and other dwarf stars. |
| B．Scientists did not find a good place to observe dwarf stars according to the passage. |
| C．Trappist-1 and other dwarf stars don't provide as much heat and light as our sun can. |
| D．Scientists have observed dwarf stars, but they failed to find the possibility of survival. |
| A．Stronger | B．More powerful | C．Less bright | D．Less beautiful. |
| A．Scientists have found a second Earth. |
| B．People will move to another Earth soon. |
| C．Scientists are planning to explore another planet. |
| D．A new solar system may become home for humans. |
Humans have always looked up at the stars and wanted to learn more about space.
In the mid-20th century, rockets that were
6 . A radio signal detected by an Australian telescope in 2019, which seemed to be coming from the star closest to the Sun, was not from aliens, researchers report today in two papers in Nature Astronomy.
“It is human-made radio interference (干扰) from some technology, probably on the surface of the Earth,” says Sofia Sheikh, an astronomer at the University of Berkeley. But the signal, detected by Breakthrough Listen — an organization in search of aliens — looked interesting enough at first that it sent astronomers on a nearly year-long research to understand its origins.
“It’s really valuable for us to have these experiences,” says Jason Wright, the leader astronomer of the organization. “We need these signals so we can learn how we will deal with them — how to prove they are alien or human-made.”
Since 2016, Breakthrough Listen has used telescopes around the world to listen for possible broadcasts from alien civilizations. The program has picked up millions of signals of unknown origin, nearly all of which could be classified as coming from radio interference on Earth, from sources such as mobile-phone towers or aircraft radar.
The 2019 signal was different. It was detected by the radio telescope in southeastern Australia and came from the direction of Proxima Centauri — the nearest star to the Sun. Proxima Centauri is of great interest to alien researchers not just because it is nearby. The star has at least two planets, one of which orbits at the right distance for liquid water to be on its surface. Breakthrough Listen even plans to send a tiny spacecraft to this planet in the future to look for life there.
In November 2020, and in January and April this year, the researchers pointed telescope at Proxima Centauri to see if they could pick up the signal again. They could not. Instead, the team spotted other “look alike signals”. These signals had been proved out by the team’s analysis as being earthly interference. Further analysis showed that these signals were all interference from an unknown source, maybe electronic equipment that got shut down or fixed
The Universe gives us a “haystack (干草堆)”, says Sofia Sheikh. “It is our need to find the needle in it, and make sure that it is actually a needle that we found.”
1. Who devoted much efforts to the research of the 2019 signal?| A．Some scientists in southeastern Australia. |
| B．An astronomer at the University of Berkeley |
| C．The leader astronomer of Nature Astronomy. |
| D．An alien research organization Breakthrough Listen. |
| A．They sent a spacecraft to Proxima Centauri. |
| B．They confirmed the origin of similar signals. |
| C．They got signals from the same direction again. |
| D．They found some dead electronic equipment. |
| A．It's very hard to direct an alien signal. |
| B．There are too many unknown signals. |
| C．There are very few needles in universe. |
| D．They should give up the research of aliens. |
| A．Alien research moved a step forward |
| B．Signals from aliens were picked up |
| C．Signals interfered Astronomy research |
| D．Mysterious alien beacon was false alarm |
7 . Just as it does on Earth, it snows on Mars. However, scientists have found that Martian snow is “dustier” than it is on Earth, which could mean it’s warmer and more likely to melt into water, a new study suggests.
“There is a chance that this dusty and dark ice might melt a few centimeters down,” said the study’s lead author, Aditya Khuller, in a statement.
In June, a separate study suggested that there maybe more water on the Red Planet than previously thought, including “dozens” of lakes less than a mile beneath the surface of the Red Planet.
The scientists believe that the ice that was dug up by the Phoenix lander in 2008 (and subsequent falling snow) occurred from a snowfall sometime over the past million years.
“It is widely believed that Mars has experienced multiple ice ages throughout its history, and it looks like the ice being exposed throughout the mid-latitudes of Mars is a relic of this ancient dusty snowfall,” Khuller added.
If researchers are able to better learn about the prospects of water on Mars, then they may be able to better learn about its prospects for once hosting life.
“Characterizing these properties can significantly improve models of ice stability on Mars and inform us about its age and origin,” the researchers wrote in the study.
The researchers say that more work is required to determine if the ice actually melts into water.
Kuller added, “We are working on developing improved computer simulations of Martian ice to study how it evolves over time, and whether it might melt to form liquid water. The results from this study will be integral to our work because knowing how dark the ice is directly influence how warm it gets.”
Although scientists confirmed in 2018 that Mars still has lakes filled with liquid water, it has been somewhat difficult to find.
1. Why does the ice on Mars melt easier than that on Earth?| A．Because Mars’ ice is dustier and darker. | B．Because it snows more often on Mars. |
| C．Because Mars’ ice is exposed to the sun for long. | D．Because the temperature is not stable on Mars. |
| A．To help reduce ice’s meiting on Mars. | B．To better learn if Mars is potentially capable of hosting life. |
| C．To accelerate its turning into water. | D．To research how much water there is on Mars. |
| A．Impossible. | B．Unbelievable. | C．Essential. | D．Interesting. |
| A．It’s easy to find lakes with liquid water on Mars. |
| B．The Phoenix lander was the first explorer to land on Mars. |
| C．It’s impossible to learn the origin of Mars’ ice. |
| D．Scientists are striving for improving ice stability on Mars. |
8 . Since I was born and brought up in a rural town，I have a great interest in nature.Using the chance of studying abroad in my second year at college，I decided to go to Canada just because I wanted to see the beautiful phenomena there.So after I finished the study program，I went to Yellowknife in the Northwest Territories.
I clearly remember the sixth night in Yellowknife.Suddenly my host mother came to my room around 8∶00 p. m.and told me to change clothes and go outside quickly carrying her camera.
The northern lights were flickering (闪烁) in the sky！I was shocked and just stood there with my mouth open.I forgot to take pictures of the mysterious lights.
Since that night，whenever it was sunny，I went outside at night and looked at the sky.It was so cold that I lost all feeling in my hands and feet.
As I took pictures of the northern lights，I came to find a characteristic movement of the lights.They first appear in the north part of the sky and then they gradually come down to the south part of the sky.After that，suddenly，they come in the middle of the north and south only for a while，which is the time when the best northern lights can be seen.Since it is only a few seconds for the northern lights to come down to the middle of the sky，it is very hard to get good pictures.
The stronger the sun acts，the better and stronger the northern lights flicker in the sky.That's because they come about from the collisions (碰撞)between atmospheric gases and the solar wind.Much more solar wind comes to the earth when the sun is active，which leads to the best northern lights.And the colors of the northern lights depend on the height of the collisions and the kinds of gases.
1. What does the last paragraph mainly tell us?| A．Ways to take good pictures. |
| B．The relationship between the sun and the northern lights. |
| C．The colors of the northern lights. |
| D．The time of the best northern lights. |
| A．She wanted to take a picture of him. |
| B．She wanted to take a walk with him. |
| C．She wanted to tell him something important. |
| D．She wanted him to see the northern lights. |
| A．the host mother didn't remind him to take the camera |
| B．he was shocked by the wonderful sight |
| C．the lights flickering in the sky disappeared too soon |
| D．he lost all feeling in his hands and feet |
| A．When they appear in the north part of the sky. |
| B．When they come down to the south part of the sky. |
| C．When they are between the north and south. |
| D．When they rise in the east part of the sky. |
9 . When Did the First Stars Shine
Our universe is home to countless galaxies(银河), with each galaxy hosting hundreds of billions of stars. Each one is a ball of energies powered by the nuclear explosion of elements in their hearts.
Billions of years ago, there was a time before stars or before lights, called the Dark Ages. There used to be not enough material of high densities(密度)to cause nuclear explosion. Without nuclear explosion, there were no stars.
Those first stars burned fiercely and died quickly. None of them survived to the present day.
Recently, a team of astronomers used 70 hours of observing time to take pictures of six extremely distant galaxies.
Hopefully, upcoming missions, like NASA's James Webb Space Telescope, will be able to directly observe those galaxies in greater detail. And some star mysteries will be disclosed,
| A．Nevertheless, they left their mark. |
| B．Accordingly, there was no visible light either. |
| C．Each one also poured out light into the empty universe. |
| D．It was much darker than it is today with only a little light. |
| E．For example, when did the Cosmic Dawn exactly take place? |
| F．Based on their observations, they were able to estimate the age of the galaxies. |
| G．They're so far away that we can't capture them even with powerful telescopes. |
Three Chinese astronauts recently arrived at the Country’s new space station in another step forward for the growing space power. The three-member crew will stay for three months in the station's main living space
Up to now, China
China was banned from drawing the ISS. It's likely, however,
