Sujet: Science
Mes profils pour cette activité: Communicateur - Investigateur - Instruit
Les savoir-être utilisés: La curiosité - L'enthousiasme - L'émerveillement - La confiance en soi
J'ai choisi ce travail parce que c'est un excellent article de journal.
Mes profils pour cette activité: Communicateur - Investigateur - Instruit
Les savoir-être utilisés: La curiosité - L'enthousiasme - L'émerveillement - La confiance en soi
J'ai choisi ce travail parce que c'est un excellent article de journal.
A Curious Rover “Curiosity” Explores Mars
D. K.
Science, Grade 9
Teacher : Doctor Farhana
Académie de la Capitale
January 11, 2013
A Curious Rover “Curiosity” Explores Mars
By: D. K.
At 01:30 a.m. EST time Sunday, August 6, 2012, 3.2 million people were biting their nails and avidly watch a TV screen. Why were so many people up at such an early hour, you ask? They were curious about a 1,982 pound, nuclear-powered Mars rover named Curiosity that had made a dramatic landing on Mars. This 2.5 billion US dollar robot took eight years to construct. It is the fourth rover to land on Mars, and it is five times the weight of its two predecessors, Spirit and Opportunity. It was launched from Cape Canaveral, Florida at 10:02 a.m. EST Saturday, November 26, 2011.
After a 563, 270, 400 km journey, which took Curiosity 8 months and 11 days, the rover finally landed on Mars. It landed inside a 150 km-wide impact crater, Mars’ Gale Crater.
Landing
Curiosity could not use the air-cushion type of landing manoeuvre as previous rovers due to its large size. It dramatically used an experimental manoeuvre called the sky crane touchdown system. Curiosity was packed into an aeroshell to protect it on its journey to Mars. When it was about 125 kilometers above the surface of Mars, the aeroshell released a 16 meter diameter parachute to slow down the landing. A heat shield from the bottom of the shell fell away, followed by the rest of the shell. A device called the "sky crane", using eight jets, lowered Curiosity gently to the ground. The manoeuvre was successful, much to the delight of many scientists and fans the world over.
Curiosity’s toolbag
Curiosity is equipped with many high-tech tools. It has 17 cameras, including its ChemCam, a chemistry camera that shoots invisible infrared wavelengths at the intended target. It uses spectrometers to determine the target’s chemical components. The rover also has an “arm” that drills into rocks, and then uses a brush, a scoop, and a sieve to examine the samples. Curiosity studies its samples and does scientific tests on Mars, instead of sending the samples back to earth. Curiosity can work day and night because it is nuclear powered. It will not be as limited by dust and the need for sun exposure as the other rovers that used solar panels.
Curiosity’s Discoveries
The purpose of sending Curiosity to Mars was to see if Mars could have sustained life. It has made a few discoveries in the past few months, including some carbon compounds in the ground. Carbon is essential for life on earth, as is water and oxygen, it is the building block of all organic compounds. "Just finding carbon somewhere doesn't mean that it has anything to do with life, or the finding of a habitable environment," says lead scientist John Grotzinger of the California Institute of Technology. The carbon could have come from earth, on the rover, or on another celestial object, most likely a comet or asteroid.
Curiosity is also attempting to understand the Mars methane cycle. In 2003, scientists found that methane was globally distributed on Mars. At that time, it was predicted that the cycle for the methane to be produced and then destroyed would be about 300 years. The cycle would last that short a time because the methane is exposed to powerful ultraviolet energy which is “a form of electromagnetic radiation that Mars' atmosphere is bathed in.” Scientists were surprised to discover that the cycle was amazingly only 1 year long! The cause of this unexpected phenomenon is not yet understood. On Earth, almost all methane is produced by life forms, which leads to the hypothesis that, on Mars, there might be an undiscovered substance that produces the methane, possibly a life form that lies below the surface. There might also be a life form that absorbs the methane. Scientists are further researching this topic to see if life exists on Mars. There is a lot on Mars that remains to be discovered.
New Mars Rover?
NASA has decided to send another Mars rover in 2020. They will make the rover much like Curiosity, using same blueprints and maybe even using spare parts for minimal costs. NASA hopes that the new rover will be able to send back martian rocks for scientists to study. Curiosity is proving to be a very successful mission and the hopeful predecessor for many more.
Summary
Curiosity, a nuclear-powered Mars rover, has been sent to Mars to discover if the Red Planet can sustain life. This large and complicated machine has been launched, travelled through space, and, using a new landing technique, landed on target. It has already discovered chemical compounds and thus far has exceeded all expectations.
After a 563, 270, 400 km journey, which took Curiosity 8 months and 11 days, the rover finally landed on Mars. It landed inside a 150 km-wide impact crater, Mars’ Gale Crater.
Landing
Curiosity could not use the air-cushion type of landing manoeuvre as previous rovers due to its large size. It dramatically used an experimental manoeuvre called the sky crane touchdown system. Curiosity was packed into an aeroshell to protect it on its journey to Mars. When it was about 125 kilometers above the surface of Mars, the aeroshell released a 16 meter diameter parachute to slow down the landing. A heat shield from the bottom of the shell fell away, followed by the rest of the shell. A device called the "sky crane", using eight jets, lowered Curiosity gently to the ground. The manoeuvre was successful, much to the delight of many scientists and fans the world over.
Curiosity’s toolbag
Curiosity is equipped with many high-tech tools. It has 17 cameras, including its ChemCam, a chemistry camera that shoots invisible infrared wavelengths at the intended target. It uses spectrometers to determine the target’s chemical components. The rover also has an “arm” that drills into rocks, and then uses a brush, a scoop, and a sieve to examine the samples. Curiosity studies its samples and does scientific tests on Mars, instead of sending the samples back to earth. Curiosity can work day and night because it is nuclear powered. It will not be as limited by dust and the need for sun exposure as the other rovers that used solar panels.
Curiosity’s Discoveries
The purpose of sending Curiosity to Mars was to see if Mars could have sustained life. It has made a few discoveries in the past few months, including some carbon compounds in the ground. Carbon is essential for life on earth, as is water and oxygen, it is the building block of all organic compounds. "Just finding carbon somewhere doesn't mean that it has anything to do with life, or the finding of a habitable environment," says lead scientist John Grotzinger of the California Institute of Technology. The carbon could have come from earth, on the rover, or on another celestial object, most likely a comet or asteroid.
Curiosity is also attempting to understand the Mars methane cycle. In 2003, scientists found that methane was globally distributed on Mars. At that time, it was predicted that the cycle for the methane to be produced and then destroyed would be about 300 years. The cycle would last that short a time because the methane is exposed to powerful ultraviolet energy which is “a form of electromagnetic radiation that Mars' atmosphere is bathed in.” Scientists were surprised to discover that the cycle was amazingly only 1 year long! The cause of this unexpected phenomenon is not yet understood. On Earth, almost all methane is produced by life forms, which leads to the hypothesis that, on Mars, there might be an undiscovered substance that produces the methane, possibly a life form that lies below the surface. There might also be a life form that absorbs the methane. Scientists are further researching this topic to see if life exists on Mars. There is a lot on Mars that remains to be discovered.
New Mars Rover?
NASA has decided to send another Mars rover in 2020. They will make the rover much like Curiosity, using same blueprints and maybe even using spare parts for minimal costs. NASA hopes that the new rover will be able to send back martian rocks for scientists to study. Curiosity is proving to be a very successful mission and the hopeful predecessor for many more.
Summary
Curiosity, a nuclear-powered Mars rover, has been sent to Mars to discover if the Red Planet can sustain life. This large and complicated machine has been launched, travelled through space, and, using a new landing technique, landed on target. It has already discovered chemical compounds and thus far has exceeded all expectations.
Bibliography
http://en.wikipedia.org/wiki/Mars_Science_Laboratory
http://www.aljazeera.com/indepth/inpictures/2012/08/201285112832621706.html
http://www.aljazeera.com/news/americas/2012/08/201285224041596944.html
http://www.jpl.nasa.gov/education/marsrover.cfm
http://mars.jpl.nasa.gov/msl/mission/timeline/edl/
http://focustaiwan.tw/ShowNews/WebNews_Detail.aspx?&ID=201212300016
http://www.pcmag.com/article2/0,2817,2408028,00.asp
http://mars.jpl.nasa.gov/msl/multimedia/interactives/learncuriosity/index-2.html
http://www.newscientist.com/article/dn22571-curiosity-finds-carbon--but-is-it-from-mars.html
http://www.aljazeera.com/indepth/opinion/2012/11/201211414422680111.html
http://www.newser.com/story/158768/nasa-were-sending-a-new-rover-to-mars.html
http://en.wikipedia.org/wiki/File:PIA16239_High-Resolution_Self-Portrait_by_Curiosity_Rover_Arm_Camera_square.jpg