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  • In 2004, 2 robotic geologists named Spirit and Opportunity landed on opposite sides of

  • the red planet. With far greater mobility than the 1997 Mars Pathfinder, these robotic

  • explorers have trekked for miles across the Martian surface, conducting field geology

  • and making atmospheric observations. During the roverslandings parachutes deployed

  • to slow the descending spacecraft, rockets fired to slow them still more just before

  • impact, and airbags inflated to cushion their landing.

  • After bouncing and rolling to a halt, a protective structure of petals opened and brought the

  • landers to an upright position, providing a platform from which the rovers drove onto

  • the Martian surface. Since leaving their landing sites, the twin

  • rovers have sent more than 100,000 spectacular, high-resolution, full-color images of the

  • Martian terrain as well as detailed microscopic images of rocks and soil surfaces to Earth.

  • Each rover weighs nearly 400 pounds. Their initial warranties of 90 days on Mars has,

  • to everyone’s surprise and delight, has turned into years.

  • It can take nearly 20 minutes for radio signals sent from earth to reach Marsso the Rovers

  • couldn’t be driven in real time. Typical speed was just yards per hourbut Rover

  • driving was always a white knuckle experience. After an 8-week, mile and a half trek through

  • a desert of broken lava, Spirit finally reached the Columbia Hills. After reaching the Columbia

  • Hills Spirit found a variety of rocks indicating that early Mars was characterized by impacts,

  • explosive volcanism, and subsurface water….but it had become a monumental challenge for Spirit

  • because its solar panels….its only source of energy had gotten dusty and produced just

  • half as much power as they used to. Over 1,300 commands were sent to Spirit in

  • an attempt to elicit a response but no communication has been received from Spirit since March

  • 22, 2010. Its total mileage remains unchanged at 4.80 miles. A series of attempts to revive

  • Spirit finally ended. What is really important is not only how long Spirit worked or how

  • far Spirit drove, but how much exploration and scientific discovery Spirit accomplished.

  • Opportunity however continues to function.

  • The next generation Rover however is ready to carry on with even more advanced instrumentation……and

  • its name is CURIOSITY. Curiosity is almost twice as long and five

  • times heavier (2,000 pounds) as Spirit and Opportunity. But before Curiosity can explore

  • Mars, it has to get there. The nose cone, or fairing, carrying the Mars

  • Science Laboratory (Curiosity) falls open like a clamshell and falls away. After this,

  • the rocket’s first stage cuts off and drops into the Atlantic Ocean.

  • The rocket’s second stage, a Centaur engine, is started and boosts the spacecraft out of

  • Earth orbit and sends it toward Mars. Once the spacecraft is in cruise stage toward

  • Mars, it begins communicating with Earth. The last stage gives the spacecraft a final

  • push for its 8 ½ month cruise to the red planet.

  • Hitting the atmosphere at about 13,000 miles per hour, the spacecraft begins to slow down.

  • While slowing down, the spacecraft uses thrusters to help steer toward the landing site.

  • It throws off weights to rebalance the spacecraft, so that it is lined up for the parachute deployment.

  • Once it is below the speed of sound, the heat shield separates and the spacecraft looks

  • for the ground with the landing radar. Once it reaches an altitude of about 1 mile,

  • the spacecraft drops out of the back-shell at about 200 miles an hour. It then fires

  • up the landing engine to slow it down even further.

  • Once it has descended to about 60 feet above the ground, and going only about 2 miles per

  • hour, the rover separates from the descent stage. As the rover is lowered, the wheels

  • deploy in preparation for landing. Once the rover is safely on the ground, and

  • touchdown has been detected, the descent stage cuts the rover loose. It flies away leaving

  • Curiosity safe on the surface of Mars. One of the first things Curiosity does after

  • landing is to deploy the mast, which supports many cameras and instruments.

  • The Curiosity rover has 10 science instruments including:

  • A gas chromatograph, a gas spectrometer, and a tunable laser spectrometer to identify a

  • wide range of organic compounds. An x-ray diffraction and fluorescence instrument

  • named CheMin designed to identify and quantify minerals in rocks and soils.

  • A Hand Lens Imager to take extreme close-up pictures of rocks and soil revealing details

  • smaller than the width of a human hair. An Alpha Particle X-Ray Spectrometer to detect

  • different elements in rocks and soils. A Camera mounted on the Mast capable of capturing images

  • of the rover’s surroundings in high resolution and color.

  • An instrument named ChemCam capable of vaporizing thin layers of material from rocks or soil

  • designed to identify atoms and capture detailed images of the area.

  • The drill on the arm allows it to grab some of that rock and deliver it to the laboratory

  • instruments inside the body of the rover. And the Radiation Assessment Detector to analyze

  • the radiation environment at the surface. This information will be necessary for planning

  • human exploration of Mars and its ability to sustain life.

  • Those instruments can get us even closer to understanding whether life could have existed

  • on Mars.

  • Curiosity will be exploring the red planet for at least 2 years ……and ….there’s

  • no telling what we will discover.

In 2004, 2 robotic geologists named Spirit and Opportunity landed on opposite sides of

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女紀錄片解說員--火星車從精神與機遇到好奇心 - 字幕 (Female Documentary Narrator - Mars Rovers From Spirit & Opportunity To Curiosity - SUBTITLES)

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    Maurice Han 發佈於 2021 年 01 月 14 日
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