Astronomers have captured(捕获) the first direct image of a planet being born.
Adam Kraus, of the University of Hawaii’s Institute for Astronomy, said the planet is being formed out of dust and gas circling a 2-million-yea-old star about 450 light years from Earth.
The planet itself, based on scientific models of how planets form, is believed to have started taking shape about 50,000 to 100,000 years ago.
Called LkCa 15b, it’s the youngest planet ever observed. The previous record holder was about five times older.
Kraus and his colleague, Michael Ireland from Macquarie University and the Australian Astronomical Observatory, used Keck telescopes on Mauna Kea(a volcano on the island of Hawaii, US) to find the planet. Kraus presented the discovery Wednesday at NASA’s Goddard Space Flight Center in Maryland.
Observing planets while they’re forming can help scientists answer questions like weather planets form early in the life of a star or later, and whether they form relatively close to stars or father away.
Planets can change orbits(轨道) after forming, so it’s difficult to answer such questions by studying older planets.
“These very basic questions of when and where are best answered when you can actually see the planet forming, as the process is happening right now,” Kraus said.
Scientists hadn’t been able to see such young planets before because the stars they’re circling around outshine(光亮强过) them. Kraus and Ireland used two techniques to overcome this problem.
One method, which is also used by other astronomers, was to change the shape of the telescope mirrors to remove light distortion(扭曲) created by the Earth’s atmosphere. The other method they used, which was unique, was to put masks with several holes over most of the telescope mirrors. The combination of these techniques allowed the astronomers to obtain high-quality images that let them see the planet next to the bright star.
The star LkCa 15—the planet is named after its star—was the team’s second target. They immediately knew they were seeing something new, so they plan to gather more data on the star.
1.The research on younger planets helps scientists _____________.
A. study why planets change orbits after forming
B. understand how planets move around their stars
C. answer questions about the age of stars and planets
D. know the relationship between planets and their stars
2.Why are young planets like LkCa 15b hard to discover?
A. Their stars are brighter than them.. B. They are very far from the earth.
C. They are generally too small. D. They rarely form.
3.According to the text, Kraus and Ireland _____________.
A. have been working in the same university
B. observed the planet on a volcano in Hawaii
C. used two new methods in the observation
D. cut holes in the mirrors when observing
4.Which of the following would be the best title for the text?
A. Youngest planet seen as it’s forming.
B. Planet 450 light years away discovered.
C. World’s first direct image of a planet taken.
D. New technique helps discover young planets.
Putting in water fountains(��ˮ��) at schools, and teaching children about the health benefits of water, could reduce their risk of getting extra pounds, reports a new study that is published in the latest issue of the journal pediatrics.
The findings are based on a survey in 32 elementary schools of two German cities, Dortmund and Essen. The researchers, led by Rebecca Muckelbauer, a nutrionist at the Research Institute of Child Nutrition Dortmund, weighed about 3,000 children, and asked them about their beverage(����) consumption.
At the beginning of the school year, the experts had water fountains added to 17 of the schools. The scientists also worked with teachers to carry out educational programs that promote the benefits of drinking water. In contrast to schools in the United States, there are very few schools in Germany that have water fountains.
At the beginning of the study, there were no big differences in the number of overweight children in different groups. But by the end of the school year, children in the schools with water fountains were 31 percent less likely to gain extra pounds, compared to kids who went to other schools, where water drinking was not encouraged.[��Դ:ѧ
Children in the schools with fountains, increased their water consumption from about 3 up to 4 glasses a day, while those in the other schools continued to drink an average of 3 glasses. Over the research, the number of overweight kids upped from 384 to 385 out of 1,641 at the schools with water fountains. In comparison, the number of overweight kids at the other schools increased from 339 to 364 out of 1,309, Dr. Muckelbauer said.
The experts cannot make any final conclusions and explain why the students who were encouraged to drink water were less likely to gain extra weight. Dr. Muckelbauer noted that according to a few other studies, drinking of water increases the rate at which calories are burned, while some other research suggested that water may temporarily decrease appetite.
1.According to the text, the journal Pediatrics__________.
A. may cover the subject of the health of children
B. mainly deals with the water drinking problem
C. is mainly about the mental health of kids
D. must be a journal entitled(��Ȩ) by a school
2.What do we know about the survey from the text?
A. The teacher were also encouraged to drink water.
B. The students surveyed were all overweight.
C. It surveyed children in the countryside.
D. It lasted for a whole school year.
3.The fifth paragraph is mainly about __________.
A. the technique used in the survey B. the benefits of the survey
C. the process of the survey D. the result of the survey
4.What can be learned from the last paragraph?
A. Drinking water definitely decreases appetite.
B. Further research is needed to confirm the finding.
C. The experts will encourage all the students to drink water.
D. Why students drinking more get less pounds will be clear soon.
Should students do the grading?
The Supreme Court says the practice doesn’t violate(侵犯) a student’s right to privacy, but is it right for students to grade one another?
Walter Potenza, California
The Supreme Court was absolutely correct to say it’s OK for students to grade one another’s homework, quizzes, and tests: in fact, it’s a great idea.
By grading one another’s papers and seeing the problems their classmates have, students double their exposure(暴露) to the troubles that they may meet on future exams and tests. Grading one another’s papers may be one of the best ways for students to reinforce within themselves the ways to master the most difficult parts of what they are learning.
Teachers are underappreciated and underpaid for the number of hours they have to work to be able to teach really well. Grading all their students’ papers can take hours. Some of that time and energy can be saved by spending a few minutes in class, while providing an extremely valuable learning experience.
I understand that some individuals are sensitive to their classmates seeing their work or grades. Any good teacher would be considerate of students who don’t want their classmates to grade their assignments.
Winston Smith, North Carolina
A girl moves back as her classmate announces her failing test grade and hands her the paper. The quiet classroom heats up.
With the increase in student grading over the past few years, scenes like this have become a bitter reality in schools across the nation. Teachers and schools should not advocate student grading and public announcement of grades because it provides a violation of privacy for students and causes unfair judgments and treatment by their classmates.
Since 1974, a law known as the Buckley Amendment has forbidden the release of education records in order to protect the privacy of students and their families. I strongly disagree with the Court’ s ruling that this law does not include student grading.
I can think of no greater violation of privacy than the exposure of one’s personal information to a group of peers(同龄人). This can be very embarrassing. Releasing this sort of personal information should be avoided, especially by institutions that seek to provide a supportive environment during essential years of human development.
1.The underlined word “reinforce” has the same meaning as “_________”.
A. change B. imagine C. strengthen D. create
2.Walter Potenza suggests that ______________.
A. teachers should set aside some time to grade students’ papers
B. the Supreme Court should do more research on students grading
C. teachers should guide students on how to grade homework
D. teachers should be careful not to hurt those sensitive students
3.By mentioning the example of a girl, Winston Smith wants to ____________.
A. show her weak points
B. criticize the student grader
C. tell us she is not a good student
D. present the negative effect of student grading
4.What does Winston Smith seem to agree?
A. Student grading is not related to families’ privacy.
B. The Supreme Court should change its decision.
C. The Buckley Amendment doesn’t apply to student grading.
D. Student grading is OK, but not public announcement of grades.
Little did I know that I was about to see something I would never forget at the Kentucky Association of School Administrators.
They introduced the young musician---Mr Patrick Henry Hughes. He was rolled onto the stage in his wheelchair and began to play the piano. His fingers danced across the keys as he made beautiful music.
About ten minutes into Patrick’s performance, someone came on the stage and said, “I’d like to share a seven-minute video about Patrick Hughes.” Then the lights were turned down.
Patrick Henry Hughes was born with no eyes and a tightening of the joints(关节), which left him disabled for life. However, he was fitted with artificial eyes and placed in a wheelchair. Before his first birthday, he discovered the piano. His mom said, “I could hit any note on the piano, and within one or two tries, he’d get it.” By his second birthday, he was playing records people asked for. His father was ecstatic. “We might not play baseball, but we can play music together.”
Today, Patrick is a junior. His father attends classes with him and he’s made nearly all A’s. He’s also a part of a 214-member marching band(游乐乐队). He’s a blind, wheelchair-bound trumpet player; he and his father do it together. In order to attend Patrick’s classes and every band practice, his father works the night shift(夜班) at United Parcel Service. Patrick says, “My dad’s my hero.”
On stage, between songs, Patrick talked to the audience about his life and about how blessed he was, “God made me blind and unable to walk. BIG DEAL! He gave me musical gifts and the great opportunity to meet new people.”
When his performance was over, the crowd rose to their feet and cheered for over five minutes.
1.The underlined word “ecstatic” could be replaced by “_________”.
A. relaxed B. disappointed C. anxious D. delighted
2.What do we know about Patrick’s father?
A. He taught Patrick to play the piano.
B. He does part-time jobs in the daytime.
C. He accompanies Patrick in class and practice.
D. He expects Patrick to become a famous musician.
3.We know from the text that Patrick Henry Hughes ______________.
A. began to play the piano at age two
B. is in charge of a marching band
C. is now a high school student
D. admires his father greatly.
4.The story of Patrick Henry Hughes mainly teaches us to _______________.
A. develop an interest in music
B. be grateful for what we have
C. be ready to help people in trouble
D. work hard to achieve great success
The concept of solitude(独处) in the digital world is almost non-existent. In the world of digital technology, e-mail, social networking and online video games, information is meant to be ______. Solitude can be hard to discover ______it has been given up. In this respect, new technologies have ______our culture.
The desire to be connected has brought solitude to a(n) as we've known it. People have become so in the world of networks and connections that one can often be contacted they'd rather not be. Today we can talk, text, e-mail, chat and blog (写博客), not only from our , but from our mobile phones as well.
Most developed nations have become on digital technology simply because they've grown accustomed to it, and at this point not it would make them an outsider. , many jobs and careers require people to be . From this point of view, technology has changed the culture of work. Being reachable might feel like a to those who may not want to be able to be contacted at all times.
I suppose the positive side is that solitude is still possible for anyone who wants it. Computers can be shut and mobile phones can be turned off. The ability to be "connected" and " on" has many , as well as disadvantages. Travelers have ended up on mountains, and mobile phones have saved countless lives. They can also make people feel and forced to answer unwanted calls or to unwanted texts.
Attitudes towards our connectedness as a society across generations. Some find today's technology a gift. Others consider it a curse. Regardless of anyone's view on the subject, it's hard to imagine what life would be like daily advancements in technology.
1.A. updated B. received C. collected D. shared
2.A. though B. once C. until D. before
3.A. shaped B. respected C. ignored D. preserved
4.A. edge B. end C. stage D. balance
5.A. sensitive B. intelligent C. reachable D. considerate
6.A. only if B. even if C. as if D. if only
7.A. media B. databases C. monitors D. computers
8.A. bent B. dependent C. hard D. keen
9.A. finding B. protecting C. using D. changing
10.A. Instead B. Otherwise C. Somehow D. Also
11.A. trained B. recommended C. connected D. interested
12.A. burden B. pleasure C. benefit D. disappointment
13.A. slightly B. hardly C. merely D. really
14.A. down B. out C. up D. in
15.A. aspects B. weaknesses C. exceptions D. advantages
16.A. lost B. hidden C. relaxed D. deserted
17.A. excited B. confused C. trapped D. amused
18.A. turn B. reply C. submit D. object
19.A. arise B. spread C. vary D. exist
20.A. without B. beyond C. within D. despite
---Dad, can you tell me why so many students choose to study abroad at a very young age?
---________, darling. I haven never thought about it.
A. Take your time B. You’ve got me there C. Don’t be silly D. Bad luck
