问答题
The US space agency"s (NASA) Mars rovers are celebrating a remarkable five years on the Red Planet.
The first rover, named Spirit, landed on January 3, 2004, followed by its twin, Opportunity, 21 days later.
It was hoped the robots would work for at least three months, but their longevity in the freezing Martian conditions has surprised everyone.
The rovers" data has revealed much about the history of water on the equator of Mars billions of years ago.
"These rovers are incredibly resilient considering the extreme environment the hardware experiences every day," said John Callas, project manager for Spirit and Opportunity at NASA"s Jet Propulsion laboratory in Pasadena, California. "We realize that a major component on either vehicle could fail at any time and end a mission with no advance notice, but on the other hand, we could accomplish the equivalent of four more prime missions on each rover in the year ahead."
Spirit is exploring a 150 kin-wide bowl-shaped depression known as Gusev Crater. It has found an abundance of rocks and soils bearing evidence of extensive exposure to water.
Opportunity is on the other side of the planet, in a flat region known as Meridiani Planum. Its data have shown conclusively that this part of Mars experienced liquid water on its surface. The sedimentary rocks at its study location were laid down under gently flowing surface water.
The rovers are now showing some serious signs of wear and tear.
Spirit has to drive backwards everywhere it goes because of a jammed wheel, and Opportunity"s robotic arm has a glitch in a shoulder joint because of a broken electrical wire.
There have been times also when the vehicles have been dangerously short on power because of the dust covering on their panels.
The first rover, named Spirit, landed on January 3, 2004, followed by its twin, Opportunity, 21 days later.
It was hoped the robots would work for at least three months, but their longevity in the freezing Martian conditions has surprised everyone.
The rovers" data has revealed much about the history of water on the equator of Mars billions of years ago.
"These rovers are incredibly resilient considering the extreme environment the hardware experiences every day," said John Callas, project manager for Spirit and Opportunity at NASA"s Jet Propulsion laboratory in Pasadena, California. "We realize that a major component on either vehicle could fail at any time and end a mission with no advance notice, but on the other hand, we could accomplish the equivalent of four more prime missions on each rover in the year ahead."
Spirit is exploring a 150 kin-wide bowl-shaped depression known as Gusev Crater. It has found an abundance of rocks and soils bearing evidence of extensive exposure to water.
Opportunity is on the other side of the planet, in a flat region known as Meridiani Planum. Its data have shown conclusively that this part of Mars experienced liquid water on its surface. The sedimentary rocks at its study location were laid down under gently flowing surface water.
The rovers are now showing some serious signs of wear and tear.
Spirit has to drive backwards everywhere it goes because of a jammed wheel, and Opportunity"s robotic arm has a glitch in a shoulder joint because of a broken electrical wire.
There have been times also when the vehicles have been dangerously short on power because of the dust covering on their panels.
问答题
Why is the robot" longevity in the freezing Martian conditions surprising?
【正确答案】
【答案解析】It was hoped the robots would work for at least three months.
问答题
What has Spirit found that has been exposed to water?
【正确答案】
【答案解析】It has found an abundance of rocks and soils bearing evidence of extensive exposure to water.
问答题
What"s wrong with Spirit according to the passage?
【正确答案】
【答案解析】Spirit has to drive backwards everywhere it goes because of a jammed wheel.
问答题
How many robots launched by NASA are mentioned in the passage?
【正确答案】
【答案解析】Spirit, Opportunity and Phoenix
问答题
Why will NASA and the European Space Agency combine their efforts to explore Mars in the future?
【正确答案】
【答案解析】In future for NASA and the European Space Agency will be joint affairs because of the high cost of getting spacecraft down on to the planet.