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DIRECTIONS (Qs. 97-101):
Read the following passage carefully and answer the questions given below it. Certain words/phrases are in bold to help you locate them while answering some of the questions.
Scientists have found irrefutable evidence that Mars once had the ingredients for life. This confirmation comes seven months after NASA's rover Curiosity landed on Mars. Analysis of powdered samples drilled out from inside an ancient and once watersoaked rock at the rover's Gale Crater landing site shows clays, sulphates and other minerals that are all key to life, scientists told reporters at NASA headquarters in Washington on March 12. The water that once flowed through the area known as Yellowknife Bay, was likely drinkable, said Curiosity's lead scientist John Grotzinger, who is with the California Institute of Technology. The analysis stopped short of a confirmation of organics, which are key to most Earth-like life. But with 17 months left in the rover's primary mission, scientists said they expect to delve further into that question. Science operations currently are suspended because of a computer glitch, which is expected to be resolved shortly. Whether or not Mars has or ever had life, it should have at one time at least had organic compounds delivered to its surface by organic-rich comets and asteroids. Finding places where the organics could have been preserved, however, is a much trickier prospect than finding the environmental niches and chemistry needed to support life, scientists said. In May, following a one month interruption of radio communication caused by the positions of Earth and Mars, scientists plan to drill a second hole into the Gale Crater rock to look for organic compounds. "If there was organic material there, it could have been preserved," said David Blake, principal investigator for Curiosity's Chemistry and Mineralogy, or CheMin, experiment. A lack of organics, however, would not rule out the Yellowknife Bay site as suitable for life, scientists added. "You don't have to have carbon present in a geological environment that's habitable in order to have microbial metabolism occur," Grotzinger said. Some micro-organisms on Earth, for example, can feed on inorganic compounds, such as what are found inside rocks. "There does need to be sources of carbon somewhere, but if it's just C , you can have chemoautotrophic organic compounds based on that carbon," Grozinger said. Analysis shows the Gale Crater rock contains carbon dioxide, in addition to hydrogen, oxygen, phosphorus, sulphur and nitrogen. Carbon dioxide provides a key ingredient in the building blocks for life, all of which have now been found in the Mars rock sample, Grotzinger said The $2.5-billion, nuclear-powered Curiosity rover landed inside the giant Gale Crater impact basin, located near the Martian equator, on August 6 for a two-year mission. Scientists were drawn to the area because of a five-km mountain of sediment, called Mount Sharp, rising from the crater floor. But shortly after the rover's landing, the team decided to first explore the Yellowknife Bay area, located in the opposite direction from Mount Sharp. Observations from Mars orbiters showed three different types of terrain coming together in Yellowknife Bay, plus a low elevation, all hints that water could have once flowed and pooled on the surface.
Read the following passage carefully and answer the questions given below it. Certain words/phrases are in bold to help you locate them while answering some of the questions.
Scientists have found irrefutable evidence that Mars once had the ingredients for life. This confirmation comes seven months after NASA's rover Curiosity landed on Mars. Analysis of powdered samples drilled out from inside an ancient and once watersoaked rock at the rover's Gale Crater landing site shows clays, sulphates and other minerals that are all key to life, scientists told reporters at NASA headquarters in Washington on March 12. The water that once flowed through the area known as Yellowknife Bay, was likely drinkable, said Curiosity's lead scientist John Grotzinger, who is with the California Institute of Technology. The analysis stopped short of a confirmation of organics, which are key to most Earth-like life. But with 17 months left in the rover's primary mission, scientists said they expect to delve further into that question. Science operations currently are suspended because of a computer glitch, which is expected to be resolved shortly. Whether or not Mars has or ever had life, it should have at one time at least had organic compounds delivered to its surface by organic-rich comets and asteroids. Finding places where the organics could have been preserved, however, is a much trickier prospect than finding the environmental niches and chemistry needed to support life, scientists said. In May, following a one month interruption of radio communication caused by the positions of Earth and Mars, scientists plan to drill a second hole into the Gale Crater rock to look for organic compounds. "If there was organic material there, it could have been preserved," said David Blake, principal investigator for Curiosity's Chemistry and Mineralogy, or CheMin, experiment. A lack of organics, however, would not rule out the Yellowknife Bay site as suitable for life, scientists added. "You don't have to have carbon present in a geological environment that's habitable in order to have microbial metabolism occur," Grotzinger said. Some micro-organisms on Earth, for example, can feed on inorganic compounds, such as what are found inside rocks. "There does need to be sources of carbon somewhere, but if it's just C , you can have chemoautotrophic organic compounds based on that carbon," Grozinger said. Analysis shows the Gale Crater rock contains carbon dioxide, in addition to hydrogen, oxygen, phosphorus, sulphur and nitrogen. Carbon dioxide provides a key ingredient in the building blocks for life, all of which have now been found in the Mars rock sample, Grotzinger said The $2.5-billion, nuclear-powered Curiosity rover landed inside the giant Gale Crater impact basin, located near the Martian equator, on August 6 for a two-year mission. Scientists were drawn to the area because of a five-km mountain of sediment, called Mount Sharp, rising from the crater floor. But shortly after the rover's landing, the team decided to first explore the Yellowknife Bay area, located in the opposite direction from Mount Sharp. Observations from Mars orbiters showed three different types of terrain coming together in Yellowknife Bay, plus a low elevation, all hints that water could have once flowed and pooled on the surface.
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