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https://www.nature.com/articles/s41467-024-48886-x

В 1936-1937 была проведена аэрофотосъемка береговой линии Антарктиды. В 1956-1973 гляциологи снова провели аэрофотосъемку.

В 2023 ученые из Норвегии, Дании и Франции используя эти ранние снимками провели исследование ледника в Восточной Антарктиде.
Сочетая их с современными спутниковыми снимками, ученые оценили высоту, скорость течения и фронтальные изменения ледников в заливе Лютцов-Хольм, у побережий Земли Кемпа, Земли Мак-Робертсона и вдоль берега Ингрид Кристенсен с 1937 по 2023 год. 

У ледников залива Лютцов-Хольм геологи зафиксировали отступление в период с 1937-го по 1980-е годы, в середине 2000-х (за исключением ледника Ширасе) и между 2016 и 2018 годом. 
Ледник Лангховде (Langhovde) и Ховдебрин (Hovdebreen) за 85 лет изменился менее чем на километр, а некоторые участки даже превысили площади в 1937-м. 

Абсолютные высоты остаются неизменными, а вдоль побережья Сева (Syowa) ледники растут по несколько сантиметров за год. 
Ледник Ширасе — исключение, он утолщается со скоростью полметра в год. 

Рост объема льдов совпадает с долгосрочным выпадением снега вдоль побережья Земли Кемпа и Мак-Робертсона (все недалеко от моря Содружества). Там количество осадков увеличилось почти на 50% с 1940 по 2022 год, а в заливе Лютцов-Хольм наблюдается почти постоянный снегопад. 
Предварительные выводы -- наблюдается практически непрерывное накопление массы льда в Антарктиде за последние 85 лет. 

https://web.archive.org/web/20240530153805/https://www.nature.com/articles/s41467-024-48886-x


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https://news.mit.edu/2024/tests-show-high-temperature-superconducting-magnets-fusion-ready-0304

В серии из шести научных статей в мартовском выпуске журнала IEEE Xplore учёные Массачусетского технологического института рассказали о разработке и принципах работы новых электромагнитов на основе высокотемпературной сверхпроводимости. Эта разработка названа крупнейшим за последние 30 лет прорывом в области создания коммерчески выгодных термоядерных реакторов.

Первые испытания масштабного прототипа высокотемпературного сверхпроводящего электромагнита состоялись 5 сентября 2021 года в лабораториях Центра науки о плазме и термоядерного синтеза Массачусетского технологического института (PSFC). Изделие массой около 9 тонн создало электромагнитное поле силой 20 тесла. Конструкция электромагнита была создана с нуля с использованием новых принципов и масштабные испытания должны были подтвердить правильность расчётов, моделей и самой идеи, которая на тот момент была крайне новаторской.
До появления этой разработки существующие на тот момент технологии и электромагниты уже могли создавать поля необходимой напряжённости, чтобы удерживать нагретую до 100 млн °C плазму в изоляции от стенок рабочей камеры. Однако эффективность работы подобных систем была далека от требований рентабельности. Учёные из MIT с коллегами из компании Commonwealth Fusion Systems смогли создать намного более компактные и дешёвые в производстве и поддержке электромагниты, которые позволили заявить об их впечатляющей энергоэффективности.

«За одну ночь это практически изменило стоимость ватта термоядерного реактора почти в 40 раз», как позже заявили участники эксперимента. «Теперь у термоядерного синтеза есть шанс, — утверждают учёные. — Наиболее широко используемая конструкция для экспериментальных термоядерных устройств, получила шанс стать экономичной, потому что у вас появились скачкообразные изменения в этой области». Это способность значительно уменьшить размер и стоимость объектов, которые сделали бы возможным термоядерный синтез.
Один из секретов успеха новой конструкции электромагнитов стал отказ от изоляции проводов в обмотках катушек. В это трудно поверить, но учёные использовали в обмотке голые провода без опасений пробоев и коротких замыканий. Эффект сверхпроводимости создал в обмотках такие условия, что замыканием между витками можно было пренебречь. Эксперимент подтвердил правильность выбора. Катушка электромагнита осталась надёжной и стала гораздо меньше в размерах, а также по стоимости и с точки зрения общего размера реактора.
В качестве обмотки был выбран высокотемпературный сверхпроводник REBCO — это редкоземельный оксид бария-меди, который позволяет достигать сверхпроводящего эффекта при температуре 20 К — это на 16 К выше обычной сверхпроводимости, что меняет правила игры несмотря на кажущуюся небольшую разницу в глубине охлаждения. На один электромагнит ушло 300 км полосы REBCO. Только представьте, сколько экономии пространства в катушке стало возможным благодаря отказу от изоляции этого провода. 

Позже во время испытаний магнита на критических режимах были проверены теоретические модели его поведения вплоть до частичного разрушения (расплавления обмотки). Это было важно для улучшения конструкции и отработки эксплуатационных характеристик электромагнитов для использования в будущих термоядерных реакторах. Выход сегодня статей по разработке стал возможным после получения патентов на конструкцию электромагнитов и принципы их работы. Исследование приближает тот момент, когда на Земле может зажечься рукотворное Солнце, а энергия в электросетях станет бесконечной и практически чистой.


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Deimos transit

On Sol 1037 ( Jan. 20, 2024 ) the Perseverance rover observerved this transit of Mars' smallest moon Deimos.

According to the image metadata the transit was on January 20th and started at 01:32:18 UTC and lasted until 01:34:18 UTC.

In local mean solar time on Mars this corresponds to 08:41:34 to 08:43:31.

The full sequence lasted 137 seconds in reality and is shown at 10x speed.

Credit: NASA/JPL-Caltech/ASU/Simeon Schmauß

https://www.flickr.com/photos/semeion/53481345691/


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The mysterious sea creature Dendrogramma was rated one of the top-ten new species of 2015. There was speculation it might even represent a new invertebrate phylum, a tremendously rare event. Further specimens have revealed the organism was so hard to classify because the specimens are not complete animals, as appeared, but appendages. Nevertheless, many questions remain unanswered.

In 1986, two mushroom-looking specimens were captured near the bottom of Australia's Bass Strait. Taxonomists being few and over-stretched for the abundance of unknown Australian species, the items were preserved in formalin and neglected for decades.

In 2014, Danish scientists concluded these represented no mere new species, a common enough occurrence, but a new phylum. The blog Deep Sea News compared the claim to finding a vertebrate that was neither mammal, bird, fish, or reptile. Huge news if true.

The name Dendrogramma was given for the way the creature's branching veins resemble the tree of life, on which it appeared unplaceable. The specimens lacked the stinging cells that define true jellyfish and the rows of cilia comb jellyfish use to move. Many marine biologists were skeptical of the phylum claim, but no one knew what Dendrogramma was. The closest resemblance was to 560-million-year-old fossils.

Last year, Museum Victoria's Dr. Hugh MacIntosh pulled a fresh specimen out of the waters of the Great Australian Bite. “It was a ‘eureka’ moment! Holding one up to the light, the distinctive forked veins shimmered through the transparent body, and it suddenly dawned on me that we had rediscovered the elusive Dendrogramma,” MacIntosh said.

MacIntosh and colleagues have published what they have learned in Current Biology. DNA conclusively indicated Dendrogramma is a cnidarian, related to true jellyfish. The stinging cells were absent because the scientists lacked the complete organism. Instead, what they had was a bract, an easily detachable part used for defense. It was not previously recognized as such because bracts are usually smaller and less elaborate.

Although MacIntosh told IFLScience he collected “around 80” Dendrogramma bracts on the voyage, there still isn't a complete specimen. In some cases, MacIntosh told IFLScience, the main body remains attached, but these are surprisingly small and “may be juveniles.”

The list of unanswered questions is long. “We don't know why they have such big bracts, we don't know why we collected so many bracts without complete samples and we don't know how many bracts fit on each,” MacIntosh said.

Nevertheless, he added: “They're probably like other deep sea jellies, floating just off the sea floor, anchored with small tentacles and using stinging cells to feed on crustaceans on the sea floor.” The bracts, while tenuous, provide protection against predators, or even against the fragile main Dendrogramma body.

The survey took place to assess the little-known biology of the Bite, where oil companies are seeking to drill. MacIntosh couldn't comment on whether the discovery of such an unusual species will interfere with these plans.

https://www.iflscience.com/deep-sea-species-mystery-partially-explained-36142



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Amazing new images of the moon Io have come down from the Juno spacecraft! This one shows the volcanic moon of Jupiter from only 2,800 kilometers away, which is the closest look we’ve gotten of Io since the Galileo orbiter over 20 years ago. Check out all those volcanoes!!!!
NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill

https://deepspace.social/@kevinmgill/111672868392026150
https://deepspace.social/@kevinmgill/111676796209064427


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https://youtube.com/watch?v=GvJtVOmFs5Q

NASA’s Deep Space Optical Communications experiment beamed an ultra-high definition streaming video on Dec. 11 from a record-setting 19 million miles away (31 million kilometers, or about 80 times the Earth-Moon distance). The milestone is part of a NASA technology demonstration aimed at streaming very high-bandwidth video and other data from deep space – enabling future human missions beyond Earth orbit.

“This accomplishment underscores our commitment to advancing optical communications as a key element to meeting our future data transmission needs,” said NASA Deputy Administrator Pam Melroy. “Increasing our bandwidth is essential to achieving our future exploration and science goals, and we look forward to the continued advancement of this technology and the transformation of how we communicate during future interplanetary missions.”

The demo transmitted the 15-second test video via a cutting-edge instrument called a flight laser transceiver. The video signal took 101 seconds to reach Earth, sent at the system’s maximum bit rate of 267 megabits per second (Mbps). Capable of sending and receiving near-infrared signals, the instrument beamed an encoded near-infrared laser to the Hale Telescope at Caltech’s Palomar Observatory in San Diego County, California, where it was downloaded. Each frame from the looping video was then sent “live” to NASA’s Jet Propulsion Laboratory in Southern California, where the video was played in real time.

https://en.wikipedia.org/wiki/Deep_Space_Optical_Communications


https://youtube.com/watch?v=GvJtVOmFs5Q

NASA’s Deep Space Optical Communications experiment beamed an ultra-high definition streaming video on Dec. 11 from a record-setting 19 million miles away (31 million kilometers, or about 80 times the Earth-Moon distance). The milestone is part of a NASA technology demonstration aimed at streaming very high-bandwidth video and other data from deep space – enabling future human missions beyond Earth orbit.

“This accomplishment underscores our commitment to advancing optical communications as a key element to meeting our future data transmission needs,” said NASA Deputy Administrator Pam Melroy. “Increasing our bandwidth is essential to achieving our future exploration and science goals, and we look forward to the continued advancement of this technology and the transformation of how we communicate during future interplanetary missions.”

The demo transmitted the 15-second test video via a cutting-edge instrument called a flight laser transceiver. The video signal took 101 seconds to reach Earth, sent at the system’s maximum bit rate of 267 megabits per second (Mbps). Capable of sending and receiving near-infrared signals, the instrument beamed an encoded near-infrared laser to the Hale Telescope at Caltech’s Palomar Observatory in San Diego County, California, where it was downloaded. Each frame from the looping video was then sent “live” to NASA’s Jet Propulsion Laboratory in Southern California, where the video was played in real time.

https://en.wikipedia.org/wiki/Deep_Space_Optical_Communications


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NASA Authorizes Dragonfly Mission to Proceed With Estimated 2028 Launch Readiness Date

NASA’s Dragonfly mission team is moving on to the next stage of development on the revolutionary, car-sized nuclear-powered drone it plans to fly over and land on the organic-rich sands of Saturn’s large moon Titan.

NASA has authorized Dragonfly to proceed with work on final mission design and fabrication, known as Phase C. Earlier this year, Dragonfly passed all the success criteria of its Preliminary Design Review. The team also was asked to conduct a replan of the mission based on funding levels in the fiscal year 2024 president’s budget request. That replan has been completed and reviewed with NASA, with a revised launch readiness date of July 2028. NASA will officially assess the mission’s launch readiness date in mid-2024 at the Agency Program Management Council.

“The Dragonfly team has successfully overcome a number of technical and programmatic challenges in this daring endeavor to gather new science on Titan,” said Nicola Fox, associate administrator of NASA’s Science Mission Directorate in Washington. “I am proud of this team and their ability to keep all aspects of the mission moving.”

NASA’s only mission to the surface of another ocean world, Dragonfly is designed to investigate the complex chemistry that is the precursor to life. The vehicle, which the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, will build and operate, will be equipped with cameras, sensors and samplers to examine areas of Titan known to contain organic materials that may have previously mixed with liquid water now frozen on the icy surface.

“Dragonfly is such a daring endeavor, like nothing that has ever been done before,” said APL’s Elizabeth “Zibi” Turtle, Dragonfly principal investigator. “I’m inspired by the way our team has repeatedly overcome challenges by working together and thinking outside the box. We’ve demonstrated that we’re ready for the next steps on the path to Titan, and we’ll keep moving forward with the same curiosity and creativity that have brought Dragonfly to this point.”

The Dragonfly team has made significant technical strides, among them: a progression of tests of Dragonfly’s guidance, navigation and control systems over California deserts that resemble Titan’s dunes; multiple flight-system tests in the one-of-a-kind wind tunnels at NASA’s Langley Research Center; and running a full-scale, instrumented lander model though temperature and atmospheric pressure simulations in APL’s new, 3,000-cubic-foot Titan Chamber.

“The dedicated efforts of the Dragonfly team have been nothing short of heroic,” said Bobby Braun, head of APL’s Space Exploration Sector. “Engineers, scientists and project management across APL, NASA’s Goddard Space Flight Center, the NASA Langley and Ames Research Centers, Lockheed Martin, Sikorsky and our many university and industry partners have formed a seamless team whose experience and expertise is shaping a game-changing mission of exploration. I’m very proud of this team and am confident that they will continue to mature this system in Phase C.”

APL manages the Dragonfly mission for NASA. The team includes key partners at NASA’s Goddard Space Flight Center in Greenbelt, Maryland; Lockheed Martin Space in Littleton, Colorado; Sikorsky, a Lockheed Martin company; NASA’s Ames Research Center in Silicon Valley, California; NASA’s Langley Research Center in Hampton, Virginia; Penn State University in State College, Pennsylvania; Malin Space Science Systems in San Diego, California; Honeybee Robotics in Pasadena, California; NASA’s Jet Propulsion Laboratory in Southern California; the French space agency (CNES) in Paris; the German Aerospace Center (DLR) in Cologne, Germany; and the Japan Aerospace Exploration Agency (JAXA) in Tokyo.
Dragonfly is the fourth mission in NASA’s New Frontiers Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington.

https://www.jhuapl.edu/news/news-releases/231128-dragonfly-mission-development



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