题目内容
Mars( 火星) appears to be flowing with small streams of salty water, at least in the summer, scientists reported Monday. "It suggests that. it would be possible for there to be life today on Mars," NASA's science mission chief, John Grunsfeld, said at a news conference on September 28, 2015.
The streams are about 12 to 15 feet wide and 300 feet or more long, scientists said. "What we're dealing with is wet soil. thin layers of wet soil, not standing water," said Aifred McEwen of the University of Arizona at Tueson ! the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life, the findings could have major implications for the possibility of Martian life. The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars. Water could be used for drinking and for creating oxygen and rocket fuel. NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark, narrow streaks(条痕) on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit. But salt can lower the freezing point of water and melt ice.
The source(源头) of the water is a mystery. Scientists noted it could be melting ice. It could be an underground aquifer, which is rock or sand that can hold water. It is possibly water vapor from the thin Martian atmosphere, Or it may be a combination.
Michael Meyer, lead scientist for NASA's Mars exploration program, said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth - something a U. S. lander set for lift-off in 2020 will do.
1.What would be the best title for the text?
A Streams of Water Spotted on Mars
B. Astronauts will Land on Mars
C. NASA's Mars Exploration Program
D. A Breakthrough in the Exploration of Mars
2.According to John Grunsfeld, there seems to be on Mars.
A. salty water
B. standing water
C. rocket fuel
D. human beings
3.Scientists are uncertain about the of the water on Mars.
A. state
B. source
C. temperature
D. taste
4.What matters to the existence of liquid water on Mars?
A. The distance from the sun.
B. The favorable climate.
C. The gravity of the earth
D.The salt in it.
Dogs Don't Tell Jokes - By Louis Sachar Twelve-year-old Gary Boone knows he was born to be a comedian. He never stops joking, regardless of the fact that nobody laughs much and his classmates think he is stupid. Therefore he had no real friends at school. Due to being laughed at by his classmates, Gary Boone thought winning the school talent show would be his dream of proving himself to be a real comedian, but on the big night his dream went wrong with funny results. | Winners Never Quit - By Mia Hamm Mia Hamm, American soccer champion, tells a true-to-life inspiring story of learning that winning and losing aren't as important as being part of a team. More than anyone, soccer superstar Mia Hamm knows the value of teamwork. She shares this lesson, paired with energetic pictures by Carol Thompson, and this story is perfect for soccer kids and their soccer moms. |
Shack let on s Incredible Voyage - By Alfred Lansing The astonishing adventure of polar explorer Ernest Shackleton's survival for over a year on the ice-bound Antarctic seas, as Time t magazine put it, "defined heroism". To write the authoritative story, Lansing consulted with ten of the surviving members and gained access to diaries and personal accounts by eight others. The book has a first-hand account, expanded with maps and illustrations especially for this edition. | The Alchemist - By Paulo Coelho The Alchemist, by Paulo Coelho, continues to change the lives of its readers forever. It tells the magical story of Santiago, an Andulusian shepherd-boy (牧童) who desires to travel in search of treasure. The story of the treasures Santiago finds along the way teaches us about the essential wisdom of listening to our hearts and above all, following our dreams. |
1.From Shackletoris Incredible Voyage, we know the main character ______.
A. is a writer for Time magazine
B. is a survival of one polar exploration
C. has left a lot of diaries and accounts
D. has formed a close friendship with Alfred Lansing
2.If you want to know more about teamwork, you can read ______.
A. Dogs Don't Tell Jokes B. Shackletoris Incredible Voyage
C. Winners Never Quit D. The Alchemist
3.What do we know about The Alchemist?
A. It has an everlasting influence on its readers.
B. It gives people magical power over their dreams.
C. It tells a story of how to find treasures.
D. It is mainly about the wisdom of listening to others.