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  • The Sun is an unpredictable, violent ball of gas and plasma, radiating fusion energy.

  • It can send streams of charged particles right towards Earth without warning, potentially

  • causing catastrophic damage to our power grid.

  • And while we need the Sun to live, we also need to protect ourselves from its wrath.

  • The problem is, we actually know very little about our nearest star because

  • we haven't been able to get close enough to fully understand its behavior.

  • But finally NASA believes it has the tech to touch the Sun.

  • The Parker Solar Probe is humanity's first trip to a star.

  • It will get seven times closer to the Sun than any mission before, and that's because

  • of the probe's Thermal Protection System or TPS.

  • The spacecraft and its instruments are shielded by an 11 centimeter thick piece of carbon

  • foam sandwiched between two panels of superheated carbon-carbon composite.

  • The TPS will enable the front of the shield to withstand temperatures as high as 1,370

  • degrees Celsius, while the inside of the probe remains at the comfortable heat of a summer day - about 30 degrees Celsius.

  • Twin solar arrays will power the spacecraft and its cooling system, which surprisingly utilizes a low-tech coolant: pressurized water.

  • The ability to function in extreme heat is incredibly important because the Parker probe

  • will venture to the corona - the Sun's outermost atmosphere.

  • There, the data it collects will help answer two of the most vexing questions in astrophysics:

  • why the corona is hotter than the solar surface and how solar wind is accelerated.

  • From Earth, we can only ever see the corona during a total solar eclipse, which is why it is incredibly difficult to study.

  • Because the density is so low, the corona's brightness is overpowered by energy coming from the solar surface.

  • As the last layer of the Sun's atmosphere,

  • the corona extends millions of miles into space.

  • Here temperatures can rise to over 1 million degrees Celsius, which is about 300 times

  • hotter than the photosphere- the lowest layer of the Sun's atmosphere.

  • At this extreme heat, the Sun's gravity can't hold on to rapidly moving particles charged

  • in the corona, so they escape in streams of accelerated plasma, known as solar wind.

  • These streams carry the Sun's magnetic field

  • far into space at speeds up to 800 kilometers per second.

  • There are theories about the causes of coronal heating and solar wind acceleration, but we

  • haven't been able to land on a definitive answer without actually going to the Sun,

  • and that's why the Parker Solar Probe is so crucial.

  • The spacecraft will orbit the Sun 24 times, coming as close as 5.9 million kilometers

  • and moving as fast as 690,000 kilometers per hour.

  • Once close enough, it will trace energy as it moves through the corona by measuring particle

  • properties and shock waves in the Sun's plasma.

  • If Parker manages to complete its seven year mission, its data will revolutionize the way

  • we look at the Sun by solving these longstanding solar mysteries.

  • Parker's discoveries will also help us better predict our nearest star's volatile

  • behavior and enhance our ability to forecast solar storms to avoid global disaster here on Earth.

  • If you want to see more Space Crafts, check out this playlist here.

  • And be sure to let us know in the comments what astronomical phenomena you want to learn more about.

  • Thanks for watching Seeker! Don't forget to subscribe.

The Sun is an unpredictable, violent ball of gas and plasma, radiating fusion energy.

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NASAは太陽に行っている、ここではなぜそれはとてもクレイジーだ (NASA Is Going to The Sun, Here's Why That's So Crazy)

  • 201 12
    Jerry Liu に公開 2021 年 01 月 14 日
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