Sonda New horizons, flyby a Plutão

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Eu já aqui postei um video sobre isso. Em que eles usam Marte como comparação, e depois explicam as diferenças, é só procurar aqui no tópico.

Acho que o video se chama Pluto, the other red world, ou qualquer coisa do género.
Sim mas não me apetece estar a ler Inglês e perguntei a ti para uma explicação rápida e resumida, senão tinha ido pesquisar. Mas obrigado na mesma :)
 

Albifriorento

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Isso é porque eu próprio também não compreendo muito bem o processo, nunca gostei de química.

Volto a postar o video.

Segundo este vídeo, os raios solares fazem com que alguns compostos, como o metano, se decomponham num composto chamado de Tolina.

retirado da wikipédia
https://pt.wikipedia.org/wiki/Tolina
Tolina é uma molécula formada pela ação de radiação ultravioleta solar em compostos orgânicos simples como metano e etano. Tolinas têm cor vermelha ou marrom e não são achadas naturalmente na Terra atual, mas são abundantes em corpos gelados no Sistema Solar externo, como Titã. Acredita-se também que elas são um dos precursores químicos da vida na Terra.1

O termo "tolina" foi cunhado pelo astrônomo Carl Sagan para descrever substâncias difíceis de caracterizar que ele obteve em experimentos das misturas gasosas achadas na atmosfera de Titã.2 Não é um composto específico e sim um termo usado para descrever os compostos orgânicos avermelhados achados em certos corpos.

Tolinas também foram detectadas no disco de poeira em volta do componente primário do sistema HR 4796. HR 4796A está a cerca de 220 anos-luz (67 pc) da Terra e tem uma idade estimada de 8 milhões de anos.3 4

Como vê, a sua explicação simples, na realidade não existe, visto que é essencialmente um processo químico, no qual, como eu próprio já disse, não estou à vontade.

Peço desculpa não ter respondido antes, estou com problemas no computador principal... E hoje estou de volta ao velhinho P4 :(.
 
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Albifriorento

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Boas, enquanto não há notícias novas, aproveito e, como ainda não tinha postado nenhuma foto da sonda em si, e posto uma imagem da sonda...

https://www.nasa.gov/feature/goddard/goddard-involved-in-new-horizons-from-start
09_2005_1_lg.jpg


O artigo é sobre a montagem e os instrumentos da NH.

A NH parece grande, mas comparada com a Cassini, e até mesmo a Dawn, é relativamente pequena. Foi montada para ser bastante leve, e uma das razões da baixa largura de banda nas comunicações com a terra, será a pouca energia eléctrica com que a sonda opera. Pois apesar de a energia ser produzida através de um sistema radioactivo, tal como a curiosity em Marte, para atingir o objectivo do baixo peso, ou massa se preferirem, o unidade de produção eléctrica tem que operar de forma a que a radioactividade não cause danos na sonda.

Ficam aqui alguns factos engraçados da NH: http://pluto.jhuapl.edu/Participate/learn/Fun-Facts.php

E para aqueles que quiserem construir um modelo da NH (precisam de uma impressora 3d), podem descarregar as instruções aqui: http://pluto.jhuapl.edu/Participate/learn/Models.php

Os links são do site do controlo da Missão, http://pluto.jhuapl.edu/ , o John Hopkinns applyes phisics laboratory.
 
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Albifriorento

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Boas noites.

Não tem havido muita informação da New Horizons, penso que parte da equipa estará ocupada a escolher o próximo fly-by a um KBO (Kuiper Belt Object), mas deixo um video já com um bom par de semanas, sobre a razões da NH demorar tanto tempo a descarregar a informação recolhida.


Já aqui tinha falado da baixa potência com que a sonda opera, e da necessidade de se ter uma sonda leve (razão pela qual não foram instalados escudos anti-radioactivos), mas esse é apenas parte do problema, de acordo com este vídeo.
 
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Albifriorento

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Boas notícias...

Não sei qual a precisão deste artigo, mas aqui vai...
http://spaceflightnow.com/2015/08/26/scientists-eager-for-restart-of-pluto-photo-pipeline/

Scientists eager for restart of Pluto photo pipeline

The first images from the New Horizons spacecraft since late July will come back to Earth on Sept. 5, and scientists are salivating over what the new pictures will reveal about Pluto.

Only about 5 percent of the 50 gigabits of data New Horizons collected during its nine-day encounter with Pluto has made it back to Earth, said Alan Stern, the mission’s principal investigator from the Southwest Research Institute.

“Ninety-five percent of all the data are still on the spacecraft,” Stern said Tuesday. “All the best images are still on the spacecraft, all the high-resolution mapping, almost all the high-resolution composition mapping, the vast majority of radio occultation data are still on spacecraft, (along with) observations of the small moons and Charon.”

Only seven close-up images of Pluto from New Horizons’ sharp-eyed telescopic camera have been downlinked to Earth, and those files were compressed to expedite their transmission back home.

The faraway New Horizons spacecraft, now more than 3 billion miles from Earth, can only send back data at a rate of about 2 kilobits per second, a fraction of the speed of dial-up Internet. It will take more than a year for the robotic emissary to broadcast all its measurements, including hundreds of images, to eager scientists on the ground.

“Almost everything is still on the spacecraft, so we have just sampled this dessert with a few days of intensive download right after the flyby,” Stern said in a presentation Tuesday to a NASA-sponsored group of planetary scientists focused on the outer solar system.

New Horizons spent the last six weeks beaming back data on the plasma and dust environment it encountered around Pluto, crucial measurements that will help piece together the distant world’s workings and place in the solar system.

During its July 14 flyby, the mission discovered a vast Texas-sized ice plan informally named Sputnik Planum. Shaped ice blocks — called polygons by mission scientsts — make up the frozen, craterless terrain, leading geologists to believe the ice field formed less than 100 million years ago, and may still be changing today.

Data stored on New Horizons’ recorders include much higher-resolution views of Sputnik Planum, along with spectral readings that will reveal what types of ices comprise the ice field. The information will help narrow down the age of Sputnik Planum, which tapers toward a boundary with rugged mountains of water ice in the north.

The polygons in Sputnuk Planum may form from slow bubbling driven by a mysterious underground heat source. Scientists want to know if there is a liquid ocean underneath the ice sheet, which is mainly composed of nitrogen, methane and carbon monoxide ices at temperatures near minus 391 degrees Fahrenheit.

The best images of Sputnik Planum on the ground show the region with a resolution of about 400 meters (1,300 feet), but New Horizons’ black-and-white camera took pictures with resolutions as high as 70 meters (230 feet), good enough to see something as small as the ponds in New York City’s Central Park.

The camera also captured images in stereo pairs — viewing the same place on Pluto from slightly different angles — to allow scientists to get an idea of the topography.

“The polygons may be related to some sort of thermal convection,” Stern said. “We will see. We will know a lot more about this, and actually get 3D imagery to know what’s higher and what’s lower before the year is out.”

The next set of Pluto images are due to arrive on Earth around Sept. 5, according to William McKinnon, a planetary geologist at Washington University in St. Louis who works on the New Horizons mission.

Scientists have a wish list of things they are eager to see once the photo pipeline resumes.

“There is so much stuff on-board that I just cannot wait to see,” said Cathy Olkin, New Horizons’ deputy project scientist from the Southwest Research Institute. “One of the things I’m really looking forward to the most is our high-resolution scan that we took of Pluto with the LEISA instrument … it’s the infrared spectrometer.

“Being able to get high-resolution infrared spectroscopy across the surface of Pluto to map those ices and to see what other minor species might be there, that we couldn’t detect when we’re looking at Pluto as a point of light from Earth,” Olkin said Wednesday in a Google Hangout hosted by the Kavli Foundation. “That’s one I’m really looking forward to getting down.”

Richard Binzel, a New Horizons co-investigator based at MIT, said he is waiting to see observations of Pluto’s night side made by the spacecraft after the flyby. Scientists hoped sunlight reflected by Pluto’s moon Charon would dimly illuminate the south pole’s ice cap, which is locked in a dark, century-long winter.

New Horizons also got close-up views of Charon on its way by Pluto.

The plutonium-powered space probe, about the size of a baby grand piano, sped by Pluto at 31,000 mph at a range of 7,700 miles. It approached within about 18,000 miles from Charon.

Only a handful of close-up views of Charon, which is more than half the size of Pluto at 790 miles acrss, have been returned from New Horizons so far. The images revealed giant chasms bigger than the Grand Canyon, a patch of puzzling dark material at its north pole and a sunlit hemisphere with few craters.

“I want to see those global high-resolution uncompressed images of Charon and really see where these big cracks have flowed out onto the surface, and maybe get some composition on what those flows might have been,” said Michael Brown, an astronomer at the California Institute of Technology who specializes in studying the Kuiper Belt, a ring of mini-worlds at the outer edge of the solar system where Pluto resides.

Brown discovered the dwarf planet Eris, an object more massive than Pluto but not quite as big, in 2005. The discovery prompted the International Astronomical Union’s decision in 2006 to demote Pluto into a new class of worlds called dwarf planets.

Brown said observations of Charon could help scientists learn about many other similar-sized objects in the Kuiper Belt.

“I think that’s going to tell us a lot about the mid-sized objects around the Kuiper Belt,” Brown said in Wednesday’s Google Hangout. “There are many, many Charon-like objects out there, and I’d like to learn more about all of them by looking at those images.”

Para quem não tem paciência para ler o testamento, eu ponho o resumo...

Parece que afinal de contas a transmissão de fotos tinha sido parada, provavelmente para descarregar outro tipo de dados, e estará planeado voltarem a descarregar mais fotos a partir do próximo dia 5 de setembro. Estas fotos ainda são as do dia 14 de Julho, porque por esta altura a New Horizons está já bem longe de Plutão. O alvo do próximo Fly-By, ainda não é conhecido.
 
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Albifriorento

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Boas.

Foi divulgado, pela Nasa, um potencional alvo para outro fly-by, chama-se 2014MU69, e o fly-by ainda terá de ser aprovado, devido a custos e a alguns riscos para os objectivos futuros da missão. A ser aprovada, a NH, sobrevoará 2014MU69 em Janeiro de 2019.

https://www.nasa.gov/feature/nasa-s-new-horizons-team-selects-potential-kuiper-belt-flyby-target
NASA’s New Horizons Team Selects Potential Kuiper Belt Flyby Target
NASA has selected the potential next destination for the New Horizons mission to visit after its historic July 14 flyby of the Pluto system. The destination is a small Kuiper Belt object (KBO) known as 2014 MU69 that orbits nearly a billion miles beyond Pluto.

This remote KBO was one of two identified as potential destinations and the one recommended to NASA by the New Horizons team. Although NASA has selected 2014 MU69 as the target, as part of its normal review process the agency will conduct a detailed assessment before officially approving the mission extension to conduct additional science.

“Even as the New Horizon’s spacecraft speeds away from Pluto out into the Kuiper Belt, and the data from the exciting encounter with this new world is being streamed back to Earth, we are looking outward to the next destination for this intrepid explorer,” said John Grunsfeld, astronaut and chief of the NASA Science Mission Directorate at the agency headquarters in Washington. “While discussions whether to approve this extended mission will take place in the larger context of the planetary science portfolio, we expect it to be much less expensive than the prime mission while still providing new and exciting science.”

Like all NASA missions that have finished their main objective but seek to do more exploration, the New Horizons team must write a proposal to the agency to fund a KBO mission. That proposal – due in 2016 – will be evaluated by an independent team of experts before NASA can decide about the go-ahead.

Early target selection was important; the team needs to direct New Horizons toward the object this year in order to perform any extended mission with healthy fuel margins. New Horizons will perform a series of four maneuvers in late October and early November to set its course toward 2014 MU69 – nicknamed “PT1” (for “Potential Target 1”) – which it expects to reach on January 1, 2019. Any delays from those dates would cost precious fuel and add mission risk.

“2014 MU69 is a great choice because it is just the kind of ancient KBO, formed where it orbits now, that the Decadal Survey desired us to fly by,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute (SwRI) in Boulder, Colorado. “Moreover, this KBO costs less fuel to reach [than other candidate targets], leaving more fuel for the flyby, for ancillary science, and greater fuel reserves to protect against the unforeseen.”

New Horizons was originally designed to fly beyond the Pluto system and explore additional Kuiper Belt objects. The spacecraft carries extra hydrazine fuel for a KBO flyby; its communications system is designed to work from far beyond Pluto; its power system is designed to operate for many more years; and its scientific instruments were designed to operate in light levels much lower than it will experience during the 2014 MU69 flyby.”

The 2003 National Academy of Sciences’ Planetary Decadal Survey (“New Frontiers in the Solar System”) strongly recommended that the first mission to the Kuiper Belt include flybys of Pluto and small KBOs, in order to sample the diversity of objects in that previously unexplored region of the solar system. The identification of PT1, which is in a completely different class of KBO than Pluto, potentially allows New Horizons to satisfy those goals.

But finding a suitable KBO flyby target was no easy task. Starting a search in 2011 using some of the largest ground-based telescopes on Earth, the New Horizons team found several dozen KBOs, but none were reachable within the fuel supply available aboard the spacecraft.

The powerful Hubble Space Telescope came to the rescue in summer 2014, discovering five objects, since narrowed to two, within New Horizons’ flight path. Scientists estimate that PT1 is just under 30 miles (about 45 kilometers) across; that’s more than 10 times larger and 1,000 times more massive than typical comets, like the one the Rosetta mission is now orbiting, but only about 0.5 to 1 percent of the size (and about 1/10,000th the mass) of Pluto. As such, PT1 is thought to be like the building blocks of Kuiper Belt planets such as Pluto.

Unlike asteroids, KBOs have been heated only slightly by the Sun, and are thought to represent a well preserved, deep-freeze sample of what the outer solar system was like following its birth 4.6 billion years ago.

“There’s so much that we can learn from close-up spacecraft observations that we’ll never learn from Earth, as the Pluto flyby demonstrated so spectacularly,” said New Horizons science team member John Spencer, also of SwRI. “The detailed images and other data that New Horizons could obtain from a KBO flyby will revolutionize our understanding of the Kuiper Belt and KBOs.”

The New Horizons spacecraft – currently 3 billion miles [4.9 billion kilometers] from Earth – is just starting to transmit the bulk of the images and other data, stored on its digital recorders, from its historic July encounter with the Pluto system. The spacecraft is healthy and operating normally.

New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Ala. The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.
 
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criz0r

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criz0r

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Nem tinha reparado StormRic, agradecido :).
 
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stormy

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Orion

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Numa parceria com o Consulado dos Estados Unidos da América em Ponta Delgada e com o American Corner da Universidade dos Açores, o OASA irá receber, no próximo dia 09 de Outubro, Alice Bowman, Gestora de Operações da NASA para a missão “New Horizons”, para duas palestras sobre exploração espacial com especial atenção à própria “New Horizons” que se tornou, no passado dia 14 Julho, a primeira sonda a chegar a Plutão.

A primeira palestra decorre às 14h30, na Anfiteatro B da Universidade dos Açores, e é especialmente indicada para estudantes. Os professores interessados em levar alunos podem seguir esta ligação para preencher a inscrição. A segunda palestra decorre às 21h00, nas instalações do OASA e é aberta a todo o público interessado. Após a palestra, haverá espaço para perguntas e uma pequena observação do céu nocturno.

http://www.correiodosacores.info/in...ebe-alice-bowman-gestora-de-operacoes-da-nasa
 
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