Jupiter: the "King" and His Moons
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Jupiter-Juno-2024-Arabic-3.jpgتلاطم جوی108 visiteپس از سفری بیش از پنج سال، فضاپیمای جونو در ۴ ژوئیه ۲۰۱۶ به مدار مشتری رسید. فاصله از زمین: ۱.۷۴ میلیارد مایل. در ۲۴ اکتبر، هشتمین پرواز نزدیک خود را انجام داد و از میان پوشش ابری سیاره عبور کرد و به فاصله تنها ۳۴۰۰ کیلومتری سطح مشتری رسید. ماموریت آن؟ جمعآوری دادهها و تصاویر از بزرگترین سیاره منظومه شمسی برای ارسال به زمین.
پس از تأخیر (مرحله اولیه) در انتقال دادهها، به دلیل یک مقارنه خورشیدی که در آن ارتباطات بین مشتری و زمین به دلیل نزدیکی بیش از حد آن به خورشید قطع شد، اطلاعات ذخیره شده در کاوشگر جونو به ناسا رسید و نتایج شگفتانگیز است. تصاویر، قطبهای شمالی و جنوبی مرموز سیاره و همچنین طوفانهای گازی غولپیکر را نشان میدهند.
در حالی که منتظر عبورهای نزدیک جدید هستیم، تصاویر زیبایی را که توسط کاوشگر در رابطه با غول گازی، پنجمین سیاره منظومه شمسی، ارسال شده است، به شما نشان میدهیم.MareKromium
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Jupiter-Juno-2024-Fra-5.jpgTurbulence Atmosphérique91 visiteQuelques informations de base : après un voyage de plus de cinq ans, la sonde Juno s'est mise en orbite autour de Jupiter le 4 juillet 2016. Distance de la Terre : 2,8 milliards de kilomètres. Le 24 octobre, elle a effectué son huitième survol rapproché, traversant la couche nuageuse de la planète et s'approchant à seulement 3 400 kilomètres de sa surface. Sa mission ? Collecter des données et des images de la plus grande planète de notre système solaire afin de les transmettre à la Terre.
Après un retard (phase initiale) dans la transmission des données, dû à une conjonction solaire durant laquelle les communications entre Jupiter et la Terre ont été interrompues par la proximité excessive de la planète avec le Soleil, les informations, stockées à bord de la sonde Juno, sont parvenues à la NASA, et les résultats sont stupéfiants. Les images révèlent les mystérieux pôles Nord et Sud de la planète, ainsi que d'immenses tempêtes de gaz.
En attendant de nouvelles images, nous vous présentons quelques magnifiques clichés transmis par la sonde, concernant cette géante gazeuse, la cinquième planète du système solaire.MareKromium
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Jupiter-Juno-2024-Intro.jpgатмосферная турбулентность127 visiteНесколько слов о предыстории: После более чем пятилетнего путешествия космический аппарат Juno вышел на орбиту вокруг Юпитера 4 июля 2016 года. Расстояние от Земли: 1,74 миллиарда миль. 24 октября он совершил свой восьмой близкий пролёт, пройдя сквозь облачный покров планеты и приблизившись к поверхности Юпитера на расстояние всего 3400 километров. Его миссия? Собрать данные и изображения крупнейшей планеты нашей Солнечной системы для передачи на Землю.
После задержки (начальная фаза) в передаче данных, вызванной солнечным соединением, во время которого связь между Юпитером и Землёй была прервана из-за его чрезмерной близости к Солнцу, информация, хранящаяся в зонде Juno, поступила в НАСА, и результаты поразительны. На изображениях видны загадочные Северный и Южный полюса планеты, а также гигантские газовые бури.
В ожидании новых близких пролётов мы покажем вам несколько прекрасных изображений, переданных зондом, относящихся к газовому гиганту, пятой планете Солнечной системы.MareKromium
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Jupiter-Juno-Lightning_Green.jpgGreen Light on Jupiter83 visiteIf that "Green Thing" is a true Lightning, then it is a VERY funny-looking one. But we are on Jupiter and so, everything is possible! At least, so the Scientists said, swearing on the Third Newton's Law.MareKromium
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Jupiter-Juno-Rings.jpgFrom inside the Rings101 visitenessun commentoMareKromium
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Jupiter-NO-00-022807_3.jpgJupiter! (after New Horizons' Fly-By)55 visitenessun commentoMareKromium
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Jupiter-PIA01384.jpgThe Great Red Spot, from Voyager 157 visiteOriginal caption:"This view of Jupiter was taken by Voyager 1. This image was taken through color filters and recombined to produce the color image.
This photo was assembled from three black and white negatives by the Image Processing Lab at Jet Propulsion Laboratory".
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Jupiter-PIA02401.jpgLook at Me!60 visiteWhen 17th-century astronomers first turned their telescopes to Jupiter, they noted a conspicuous reddish spot on the Giant Planet. This Great Red Spot is still present in Jupiter's atmosphere, more than 300 years later. It is now known that it is a vast storm, spinning like a cyclone. Unlike a low-pressure hurricane in the Caribbean Sea, however, the Red Spot rotates in a counterclockwise direction in the Southern Hemisphere, showing that it is a high-pressure system. Winds inside this Jovian storm reach speeds of about 270 mph.
The Red Spot is the largest known storm in the Solar System. With a diameter of about 15.400 miles, it is almost twice the size of the entire Earth and 1/6th the diameter of Jupiter itself.
The long lifetime of the Red Spot may be due to the fact that Jupiter is mainly a gaseous planet. It possibly has liquid layers, but lacks a solid surface, which would dissipate the storm's energy, much as happens when a hurricane makes landfall on the Earth. However, the Red Spot does change its shape, size, and color, sometimes dramatically. Such changes are demonstrated in high-resolution Wide Field and Planetary Cameras 1 & 2 images of Jupiter obtained by NASA's Hubble Space Telescope between 1992 and 1999(PIA01594 thru PIA01599 and PIA02400 thru PIA02402). This image was obtained in April 1997.
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Jupiter-PIA02865-1.JPGJupiter's clouds - 619 nnmts filter55 visiteThe images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15° North at the top down to the Southern Polar Region at the bottom. (...)
The most prominent feature seen in all 3 filters is the Polar Stratospheric Haze that makes Jupiter bright near the Pole. The equatorial band is also very bright in the strong 890-nnmts image and to a lesser extent in the 727 band, but is subdued in the weak 619-nnmts image. These are high, thin, haze layers that are nearly transparent at wavelengths outside the methane absorption bands.
Another prominent feature is the Great Red Spot: about a third of it appears at the right-hand edge of the frame.
It is a bright feature in methane absorption because it has extensive cloud cover reaching to high altitude.
A wisp of high thin cloud can be seen trailing off its western rim in the 2nd and 3rd image.
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Jupiter-PIA02865-2.JPGJupiter's clouds - 727 nnmts filter57 visiteAll the already mentined Jovian features have also been seen from ground-based telescopes, from NASA's HST and from NASA's Galileo spacecraft.
Chief among these features is the very dark patch seen in the weak methane image (619 nnmts) near the top-middle of the frame.
It is almost invisible in the next image (890 nnmts) and it appears to be composed of strands of bright clouds in this frame (727 nnmts).
This is a Region similar to the "hot spot" where the Galileo Probe entered Jupiter's atmosphere in 1995.
These images indicate that cloud cover is present at the higher altitudes but absent from the lower altitudes and this is also what the Galileo Probe found when it entered Jupiter's atmosphere.
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Jupiter-PIA02865-3.JPGJupiter's clouds - 890 nnmts filter58 visiteTo the North-West (above and to the left) of the dark feature is a small cloud that is bright in the 619-nnmts image but has no contrast at the other wavelengths. This is the signature expected for a thick water cloud. Another feature seen only in the weak-methane ratio is a dark ring near the center of the image.
This feature is probably a counter-clockwise rotating, upwelling core surrounded by a sinking perimeter with diminished cloudiness. The fact that it is seen only in the weak methane ratio indicates the effects of a lower-level circulation that does not penetrated to the upper ammonia cloud level and may be confined to the deeper water cloud.
The opposite behavior is evident in an oval storm that appears dark in 727 and 890 nnmts images, but is absent in the weak 619-nnmts frame. It is located to the South-West of the Great Red Spot. Further to the West - at slightly more Northerly Latitudes - are a series of small spots that are dark at all wavelengths.
These and a myriad of other contrast features at many latitudes reveal much about Jupiter's complicated cloud structure and meteorology.
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Jupiter-PIA02865-4.jpgA "deep look" in the "deep clouds" of Jupiter56 visiteFinally, this is the combination of the 3 images taken from Cassini using the 3 different filters.
This picture reveals cloud structures and movements at different depths in the atmosphere around Jupiter's South Pole. Cassini's cameras come equipped with filters that sample 3 wavelengths where Methane gas absorbs light. These are in the RED (619 nnmts) and in the NEAR-INFRARED (at 727 and 890 nnmts). Absorption in the 619 nnmts filter is weak. It is stronger in the 727 nnmts band and very strong in the 890 nnmts band where 90% of the light is absorbed by Methane gas.
Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud (which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth).
Light in the strongest methane band is absorbed at high altitude and is sensitive only to Ammonia cloud level and higher (with pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.
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