尋找系外行星

山西 雷建榮

天文學(xué)家發(fā)現(xiàn)了一顆叫作K2-18b(也叫“超級地球”)的系外行星，該行星存在和地球相似的大氣環(huán)境，但科學(xué)家稱該行星是否滿足生命存在的條件還需進一步探究。

A new study focuses on K2-18b, an exoplanet (系外行星) discovered in 2015, orbits a red dwarf star close enough to receive about the same amount of radiation from its star as Earth does from our sun.

Previously, 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 Bj?rn Benneke, a professor at the Institute for Research on Exoplanets at the Université de Montréal, 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 “l(fā)ikely 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, 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, “l(fā)ike a vacuum cleaner”, he said. This absorbed gas would have more than doubled the planet and increased its volume eight fold.

To come to these conclusions, the research team analyzed the data from Hubble Space Telescope's observations that they made between 2016 and 2017 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 too much water.

B. It is too hot to get close to.

C. It is too far from the Earth.

D It doesn't have a real surface.

2. How does K2-18b expand according to Benneke?

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.

3. What can we infer from the last paragraph?

A. Scientists have succeeded in exploring K2-18b completely.

B. It is impossible for humans to land on other Earth-like planets.

C. Scientists are making progress in studying real Earth-like planets.

D. The K2-18b planet has passed before its star eight times between 2016 and 2017.

4. What is the text mainly about?

A. The research on the K2-18b planet.

B. The solar system's environment.

C. The discovery of the K2-18b planet.

D. The exploration of the outer space.

Difficult sentence

To come to these conclusions, the research team analyzed the data from Hubble Space Telescope's observations that they made between 2016 and 2017 of the K2-18b planet passing in front of its star eight times. 為了得出這些結(jié)論，研究小組分析了來自哈勃太空望遠鏡觀察的數(shù)據(jù)，這些觀察是在2016年至2017年K2-18b行星八次經(jīng)過其恒星前時進行的。

【點石成金】To come to these conclusions為動詞不定式作目的狀語，that引導(dǎo)的是定語從句，先行詞為observations；passing in front of its star為現(xiàn)在分詞短語作后置定語。