Mary is looking for the book she lost yesterday.（ ）
A:trying to find B:trying to read C:trying to buy D:trying to borrow
Mary is looking for the book she lost yesterday.
A:trying to find B:trying to read C:trying to buy D:trying to borrow
Mary is {{U}}looking{{/U}} for the book she lost yesterday.
A:trying to find B:trying to read C:trying to buy D:trying to borrow
{{B}}第二篇{{/B}}
|
U.S. Scientists Confirm Water on
Mars
? ?NASA scientists said that Mars was covered
once by vast lakes, flowing rivers and a variety of other wet environments that
had the potential to support life.
? ?Laboratory tests aboard
NASA’s Phoenix Mars Lander have identified water in a soil sample. The lander’s
robotic arm delivered the sample Wednesday to an instrument that identifies
vapors produced by the heating of samples.
? ?"We have water," said
William Boynton of the University of Arizona, lead scientist for the Thermal and
Evolved-Gas Analyzer, or TEGA. "This is the first time Martian water has been
touched and tasted. "
? ?The robotic arm is a critical part of the
Phoenix Mars mission. It is needed to trench into the icy layers of northern
polar Mars and deliver samples to instruments that will analyze what Mars is
made of, what its water is like, and whether it is or has ever been a possible
habitat for life.
? ?The soil sample came from a trench
approximately 2 inches deep. When the robotic arm first reached that depth, it
hit a hard layer of frozen soil. Two attempts to deliver samples of icy soil on
days when fresh material was exposed were foiled when the samples became stuck
inside the scoop. Most of the material in Wednesday’s sample had been exposed to
the air for two days, letting some of the water in the sample vaporize away and
making the soil easier to handle.
? ?"Mars is giving us some
surprises," said Phoenix principal investigator Peter Smith of the University of
Arizona. "We’re excited because surprises are where discoveries come from. One
surprise is how the soil is behaving. The ice-rich layers stick to the scoop
when poised in the sun above the deck, different from what we expected, from all
the Mars simulation testing we’ve done so far. "
? ?Since landing
on May 25, Phoenix has been studying soil with. a chemistry lab, TEGA, a
microscope, a conductivity probe and cameras. The science team is trying to
determine whether the water ice ever thaws enough to be available for biology
and if carbon-containing chemicals and other raw materials for life are
present.
? ?The mission is examining the sky as well as the ground.
A Canadian instrument is using a laser beam to study dust and clouds
overhead.
? ?"It’s a 30-watt light bulb giving us a laser show on
Mars," said Victoria Hipkin of the Canadian Space Agency.
? ?A
full-circle, color panorama of Phoenix’s surroundings also has been completed by
the spacecraft.
? ?"The details and patterns we see in the ground
show an ice-dominated terrain as far as the eye can see," said Mark Lemmon of
Texas A & M University, lead scientist for Phoenix’s Surface Stereo Imager
camera. "They help us plan measurements we’re making within reach of the robotic
arm and interpret those measurements on a wider scale.
" |
Which one of the following statements is NOT meant by the writer?
A:Scientists have been trying to break the ice-rich layers of soil on Mars. B:Scientists have been surprised by how the soil on Mars behaves. C:Scientists have been trying to find out if there is life supporting material on Mars. D:Scientists have been trying to know if water ice. will melt.
Mary is{{U}} looking for{{/U}} the book she lost yesterday
A:trying to find B:trying to read C:trying to buy D:trying to borrow
（）are those programs that help find the information you are trying to locate on the WWW.
A:Windows B:Search Engines C:Web Sites D:Web Pages
（ ） are those programs that help find the information you are trying to locate on the WWW.
A:Windows B:Search Engines C:Web Sites D:Web Pages
单选题
