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Read the passages for questions 88 - 90!
TEXT 1
After two decades in space, NASA's Cassini spacecraft has ended its remarkable journey of exploration. Having expended almost every bit of the rocket propellant it carried to Saturn, operators deliberately plunged Cassini into the planet to ensure Saturn's moons remain pristine for future exploration—in particular, the ice-covered, ocean-bearing moon Enceladus, but also Titan, with its intriguing pre-biotic chemistry.
Beginning in 2010, Cassini began a seven-year mission extension in which it completed many moon flybys while observing seasonal changes on Saturn and Titan. The plan for this phase of the mission was to expend all of the spacecraft's propellant while exploring Saturn, ending with a plunge into the planet's atmosphere. In April 2017, Cassini was placed on an impact course that unfolded over five months of daring dives—a series of 22 orbits that each passed between the planet and its rings. Called the Grand Finale, this final phase of the mission brought unparalleled observations of the planet and its rings from closer than ever before.
On Sept. 15, 2017, the spacecraft made its final approach to the giant planet Saturn. But this encounter was like no other. This time, Cassini dived into the planet's atmosphere, sending science data for as long as its small thrusters could keep the spacecraft's antenna pointed at Earth. Soon after, Cassini burned up and disintegrated like a meteor.
To its very end, Cassini was a mission of thrilling exploration. Launched on Oct. 15, 1997, the mission entered orbit around Saturn on June 30, 2004 (PDT), carrying the European Huygens probe. After its four-year prime mission, Cassini's tour was extended twice. Its key discoveries included the global ocean with indications of hydrothermal activity within Enceladus, and liquid methane seas on Titan.
And although the spacecraft may be gone, its enormous collection of data about Saturn—the giant planet itself, its magnetosphere, rings and moons—will continue to yield new discoveries for decades.
Sumber: (https://saturn.jpl.nasa.gov/mission/grand-finale/overview/)
TEXT2
The final photos taken by NASA's Cassini Saturn orbiter have begun coming down to Earth, and you can see them all.
Cassini is clearing its memory ahead of its dive into Saturn's atmosphere early Friday morning (Sept. 15), a suicide plunge that will bring the storied spacecraft's 20 years in space to a dramatic, fiery end.
The newly arrived images are a fitting coda for Cassini's mission — diverse and beautiful. They capture, among other things, the potentially habitable Saturn moons Titan and Enceladus, the gas giant's graceful limb and its iconic rings.
The $3.2 billion Cassini-Huygens mission — a joint effort of NASA, the European Space Agency and the Italian Space Agency — launched in October 1997 and arrived in orbit around Saturn on the night of June 30, 2004.
A lander called Huygens piggybacked aboard the Cassini mothership, eventually touching down on Titan's frigid, otherworldly surface in January 2005. The orbiter, meanwhile, kept cruising through the Saturn system, studying the giant planet, its rings and its diverse panoply of moons.
Cassini's discoveries have fundamentally reshaped scientists' understanding of Saturn, and of the solar system's life-hosting potential. For example, the orbiter spotted lakes of liquid hydrocarbons (mostly methane) on Titan's surface, and its observations suggest that the huge moon also hosts an ocean of salty water beneath its crust.
But Cassini is running out of fuel, and mission team members want to dispose of the spacecraft responsibly before it escapes their control. They decided to steer it toward a fiery death in Saturn's atmosphere primarily to protect Titan and Enceladus — to ensure that any Earth microbes that may have hitched a ride aboard Cassini never contaminate those two possibly habitable moons.
Cassini took its last photo — a shot of the patch of atmosphere where it will meet its doom — at 12:58 p.m. PDT (3:58 p.m. EDT, 1958 GMT) Thursday (Sept. 14). Nearly two hours later, the probe began relaying all the information on its solid-state recorder to mission control, to prepare for a transition to near-real-time data transmission during its suicide plunge.
(Sumber: https://www.space.com/38165-nasa-cassini-final-saturn-photos.html)
Which of the following is the best summary of the passage?
Cassini was a spacecraft used for exploration and has sent its last ever report on Saturn back to Earth.
Cassini landed on Saturn and had been sending reports to Earth about the surface of Saturn.
Cassini was a joint project of NASA and the European Space Agency to explore the space.
Cassini arrived on Saturn in 1997 and has been taken photos of it ever since.
NASA does not make the Cassini mission available for public.
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