ＮＡＳＡ探査機、太陽に史上最接近

【ワシントンＡＦＰ＝時事】太陽軌道を周回するＮＡＳＡの無人探査機「パーカー・ソーラー・プローブ」が２４日、これまでに打ち上げられた探査機の中で太陽に最も近づいた。この際、探査機は９３０度の高温にさらされた。（図は太陽に史上最接近したＮＡＳＡの無人探査機「パーカー・ソーラー・プローブ」）
　同探査機は、２０１８年８月に７年間のミッションに向けて打ち上げられた。
　太陽に最接近したのはグリニッジ標準時（ＧＭＴ）２４日午前１１時５３分（日本時間同午後８時５３分）。ただし、太陽との距離があまりに近いと探査機との連絡が数日間途絶えるため、データの確認が可能となるのは２７日以降となる。
　ＮＡＳＡは２４日午前、ＳＮＳを通じて動画を投稿し、探査機が太陽から６１０万キロまで接近したと発表した。
　地球と太陽の距離がアメリカンフットボール場の長さ（９１．４メートル）だとすると、探査機の太陽最接近時の距離は、エンドゾーンから約４メートルの地点にあったことになる。
　探査機の熱シールドは非常に効果が高く、内部の機器は室温に近い約２９度を維持することができる。
　また、探査機は時速約６９万キロという驚異的な速度で移動している。米国の首都ワシントンと東京までを１分未満で飛行できる速度だ。
　同様のフライバイ（接近飛行）は、２０２５年３月２２日と６月１９日にも予定されている。【翻訳編集ＡＦＰＢＢＮｅｗｓ】
〔ＡＦＰ＝時事〕（2024/12/25-18:34）

NASA's pioneering Parker Solar Probe made history Tuesday, flying closer to the Sun than any other spacecraft, with its heat shield exposed to scorching temperatures topping 1,700 degrees Fahrenheit (930 degrees Celsius).
Launched in August 2018, the spaceship is on a seven-year mission to deepen scientific understanding of our star and help forecast space-weather events that can affect life on Earth.
Tuesday's historic flyby should have occurred at precisely 6:53am (1153 GMT), although mission scientists will have to wait until Friday for confirmation as they lose contact with the craft for several days due to its proximity to the Sun.
Right now, Parker Solar Probe is flying closer to a star than anything has ever been before, at 3.8 million miles (6.1 million kilometers) away, NASA official Nicky Fox said in a video on social media Tuesday morning.
It is just a total 'yay, we did it,' moment.
If the distance between Earth and the Sun is the equivalent to the length of an American football field, the spacecraft should have been about four yards (meters) from the end zone at the moment of closest approach -- known as perihelion.
This is one example of NASA's bold missions, doing something that no one else has ever done before to answer long-standing questions about our universe, Parker Solar Probe program scientist Arik Posner said in a statement on Monday.
We can't wait to receive that first status update from the spacecraft and start receiving the science data in the coming weeks.
So effective is the heat shield that the probe's internal instruments remain near room temperature -- around 85F (29C) -- as it explores the Sun's outer atmosphere, called the corona.
Parker will also be moving at a blistering pace of around 430,000 mph (690,000 kph), fast enough to fly from the US capital Washington to Japan's Tokyo in under a minute.
Parker will truly be returning data from uncharted territory, said Nick Pinkine, mission operations manager at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland.
We're excited to hear back from the spacecraft when it swings back around the Sun.
By venturing into these extreme conditions, Parker has been helping scientists tackle some of the Sun's biggest mysteries: how solar wind originates, why the corona is hotter than the surface below, and how coronal mass ejections -- massive clouds of plasma that hurl through space -- are formed.
The Christmas Eve flyby is the first of three record-setting close passes, with the next two -- on March 22 and June 19, 2025 -- both expected to bring the probe back to a similarly close distance from the Sun.