terça-feira, 2 de fevereiro de 2016

Belíssimo triângulo formado entre Lua em final de ciclo e Saturno e Antares, na madrugada de 03 de fevereiro!


Olá!

Em seguimento ao seu passeio
através o Quinteto Planetário
- os Planetas Visíveis:
Mercúrio, Vênus, Marte, Júpiter e Saturno -,
a Lua vem aproximando-se de Saturno
e formando, juntamente com o Senhor dos Aneis
e com Antares, estrela-alpha Scorpii,
um simpático triângulo
nos céus estrelados da madrugada sonolenta
em miolo da semana 
que traz o Carnaval
cantado e dançado e vivenciado
de maneiras inteiramente diversificadas
nas várias regiões
desse nosso imenso Brasil!

Lua e Saturno vêm realizando
seus andamentos aparentes
na direção da constelação do Serpentário, Ophiucus.
Porém, sabemos que existe uma proximidade ímpar
entre aos constelações do Escorpião e do Serpentário,
e, dessa maneira, Antares,a estrela-alpha Scorpii,
vem fazendo a festa desde 2015 e ainda agora
e estará fazendo a festa ao longo do ano de 2016,
em termos de acolher Saturno, o Senhor dos Aneis,
em sua vizinhança 
através as idas e vindas saturninas
pelas constelações do Escorpião e do Serpentário.


Caro leitor,
a visita da Lua a Saturno
ainda tem sua continuidade
na madrugada seguinte,
dia 04 de fevereiro,
com Selene balizando
a pequena fileira protagonizada
pelo Senhor dos Aneis
e pelo Coração do Escorpião, Antares.

Nesta Postagem,
encontre alguma informação
sobre a Sonda Cassini, da Nasa,
cumprindo suas Missões em Saturno!

Com um abraço estrelado,
Janine Milward



Stellarium

Stellarium

Stellarium

Stellarium

Stellarium

Stellarium


Caro leitor,
a visita da Lua a Saturno
ainda tem sua continuidade
na madrugada seguinte,
dia 04 de fevereiro,
com Selene balizando
a fileira protagonizada
pelo Senhor dos Aneis
e pelo Coração do Escorpião, Antares.

Confira na imagem abaixo:

Stellarium



Alguma informação
sobre a Sonda Cassini, da NASA,
cumprindo Missão em Saturno!


Cassini Saturn Orbit Insertion.jpg
"Cassini Saturn Orbit Insertion". Licenciado sob Domínio público, via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Cassini_Saturn_Orbit_Insertion.jpg#/media/File:Cassini_Saturn_Orbit_Insertion.jpg



Cassini Status
Titan (T-116) Flyby
1,400 km km (870 mi)
Feb 01 2016 (SCET)



The Cassini mission to Saturn is one of the most ambitious efforts in planetary space exploration ever mounted. A joint endeavor of NASA, the European Space Agency (ESA) and the Italian space agency, Agenzia Spaziale Italiana (ASI), Cassini is a sophisticated robotic spacecraft orbiting the ringed planet and studying the Saturnian system in detail. Cassini also carried a probe called Huygens, which parachuted to the surface of Saturn’s largest moon, Titan, in January 2005 and returned spectacular results.
Cassini completed its initial four-year mission to explore the Saturn System in June 2008, and the first extension, called the Cassini Equinox Mission, in September 2010. Now, the healthy spacecraft is making exciting new discoveries in a second extension called the Cassini Solstice Mission.
In late 2016, the Cassini spacecraft will begin a daring set of orbits called the Grand Finale, which will be in some ways like a whole new mission. The spacecraft will repeatedly climb high above Saturn’s poles, flying just outside its narrow F ring 20 times. After a last targeted Titan flyby, the spacecraft will then dive between Saturn’s uppermost atmosphere and its innermost ring 22 times. As Cassini plunges past Saturn, the spacecraft will collect rich and valuable information far beyond the mission’s original plan, including measuring Saturn’s gravitational and magnetic fields, determining ring mass, sampling the atmosphere and ionosphere, and making the last views of Enceladus.

Cassini completed its initial four-year mission to explore the Saturn System in June 2008 and the first extended mission, called the Cassini Equinox Mission, in September 2010. Now, the healthy spacecraft is seeking to make exciting new discoveries in a second extended mission called the Cassini Solstice Mission.
The mission’s extension, which goes through September 2017, is named for the Saturnian summer solstice occurring in May 2017. The northern summer solstice marks the beginning of summer in the northern hemisphere and winter in the southern hemisphere. Since Cassini arrived at Saturn just after the planet's northern winter solstice, the extension will allow for the first study of a complete seasonal period.
Cassini launched in October 1997 with the European Space Agency's Huygens probe. The probe was equipped with six instruments to study Titan, Saturn's largest moon. It landed on Titan's surface on Jan. 14, 2005, and returned spectacular results.
Meanwhile, Cassini's 12 instruments have returned a daily stream of data from Saturn's system since arriving at Saturn in 2004.
Among the most important targets of the mission are the moons Titan and Enceladus, as well as some of Saturn’s other icy moons. Towards the end of the mission, Cassini will make closer studies of the planet and its rings.


Acesse também

Cassini_Grand_Finale_Fact_Sheet_508.pdf



For more information about Cassini, visit:

This view of Saturn looks toward the unilluminated side of the rings from about 28 degrees below the ringplane.
http://www.nasa.gov/jpl/cassini/pia17162/#.U2D0RFVdVbc
Image Credit: NASA/JPL-Caltech/Space Science Institute
Christiaan HuygensPainting

Giovanni Domenico Cassini
1625 - 1712
Os Aneis e Luas de Saturno
Giovanni Domenico Cassini (PerinaldoRepública de Gênova, hoje Itália8 de junho de 1625 — Paris14 de setembro de 1712), também chamado Jean-Dominique ou Cassini I, foi um astrônomo e matemático francês de origem italiana.[1]
............................................  foi nomeado diretor do Observatório Astronômico de Paris. Apesar do observatório de Paris não ser muito bem construído para a observação astronômica, Cassini continuou com suas observações, descobrindo em 1671 e 1672 as luas de Saturno Jápeto e Reia, em 1675 uma parte escura dos anéis de Saturno, batizada com o seu nome (a Divisão de Cassini, área escura que separa os anéis A e B de Saturno e que tem cerca de 5.000 km de largura) e, em 1684, dois outros satélites do planeta dos anéis: Tétis e Dione
..........................................................................

https://pt.wikipedia.org/wiki/Giovanni_Domenico_Cassini


Christiaan Huygens (Haia14 de abril de 1629 — Haia, 8 de julho de 1695) foi um físicomatemáticoastrônomo e horologista neerlandês.
.......................................
Galileu Galilei foi o primeiro a observar os anéis de Saturno, porém seu instrumento (telescópio) não lhe permitiu identificar com clareza os anéis. Galileu acreditava, pelas imagens obtidas, que Saturno era um sistema planetário triplo. Huygens, com um telescópio mais poderoso, pôde identificar os anéis e descobrir Titã, a maiorlua de Saturno e a segunda maior do sistema solar, em 1655.
................................
https://pt.wikipedia.org/wiki/Christiaan_Huygens



Cassini-Huygens é uma sonda espacial não-tripulada enviada em missão ao planeta Saturno e seu sistema planetário. Um projeto conjunto da NASAESA (Agência Espacial Europeia) e ASI (Agência Espacial Italiana), ela consiste de dois elementos principais, o orbitador Cassini e a sonda Huygens. Lançada ao espaço em 15 de outubro de 1997, ela entrou em órbita de Saturno em 1 de julho de 2004 e continua em operação, estudando o planeta, seus satélites naturais, a heliosfera e testando aTeoria da Relatividade.
Um projeto que levou duas décadas de planejamento e desenvolvimento até seu lançamento, após uma viagem interplanetária de quase sete anos, na qual sobrevoouVênus e Júpiter, a nave entrou em órbita de Saturno na metade de 2004; em dezembro daquele ano a sonda Huygens separou-se do orbitador Cassini e em 14 de janeiro de 2005 entrou na atmosfera e pousou na superfície do maior satélite de Saturno, Titan, transmitindo imagens e dados para a Terra, na primeira vez em que um objeto construído pelo Homem pousou num corpo celeste do Sistema Solar exterior.
A Cassini-Huygens integra o Programa Flagship para os planetas exteriores, o maior e mais caro programa espacial não-tripulado da NASA. As outras missões deste programa incluem as Viking, as Voyager e a Galileu.1 A espaçonave de duas partes foi batizada em homenagem aos astrônomos Giovanni Cassini e Christiaan Huygens.
LEIA MAIS, MUITO MAIS EM 
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Ficheiro:Cassini Interplanet traject.jpg
Trajetória da Cassini-Huygens pelo Sistema Solar. Partindo da Terra a 15 de outubro de 1997, a sonda espacial chegou a Saturno em 1 de Julho de 2004.



Eventos importantes

15 de Outubro de 1997 — Cassini-Huygens lançada de Cabo Canaveral às 08:43 UTC.27
26 de Abril de 1998 — Primeira passagem pelo planeta Vénus para empurrão gravitacional, sobrevoando a superfície do planeta a 283 km de altitude e ganhando um empuxo em velocidade de 7 km/s.28
24 de Junho de 1999 — Segunda passagem pelo planeta Vénus para empurrão gravitacional.29
18 de Agosto de 1999 03:28 UTC — Passagem pelo planeta Terra para empurrão gravitacional. Uma hora e vinte minutos antes, a Cassini fez a maior aproximação à Lua a uma distância de 377 000 km, e tirou uma série de imagens de calibração. A nave sobrevoou a Terra a 1171 km de altitude e ganhou um empuxo em velocidade de 5,5 km/s.30

30 de Dezembro
 de 2000
 — Passagem pelo planeta Júpiter para empurrão gravitacional. A Cassini esteve no ponto mais próximo deste planeta neste dia, e fez muitas medições científicas. Também produziu o retrato colorido global mais detalhado de Júpiter; as menores caraterísticas têm aproximadamente 60 km de diâmetro.3223 de Janeiro de 2000 — Passagem pelo asteroide 2685 Masursky às 10:00 UTC. A Cassini fez imagens 5 a 7 horas antes a 1,6 milhões de km de distância e estimou um diâmetro de 15 a 20 km para o asteróide.31
30 de Maio de 2001 — Na viagem entre Júpiter e Saturno, notou-se o aparecimento de um "embaçamento" nas fotografias tiradas pela câmera de ângulo cerrado da Cassini. De início, foi visto numa fotografia da estrela Maia do aglomerado das Plêiades, tirada depois de um período de aquecimento de rotina.
23 de Julho de 2002 — No final de Janeiro, um teste foi feito para remover o "embaçamento" das lentes da câmara de ângulo cerrado, aquecendo-a. O objetivo foi alcançado aquecendo-se a câmera até 4 graus Celsius durante oito dias. Mais tarde, o aquecimento foi estendido para 60 dias, e a imagem da estrela Spica mostrou um melhoramento de mais de 90% quando comparado com o período anterior ao aquecimento. A 9 de Julho, a imagem mostrou que o procedimento de remoção de embaçamento foi completado com sucesso.33
10 de Outubro de 2003 — A equipe de cientistas da Cassini anunciou os resultados de um teste da teoria da relatividade de Einstein, usando sinais de rádio da sonda Cassini. Os cientistas observaram uma mudança de frequência nas ondas de rádio de e para a sonda, assim que esses sinais viajaram mais perto do Sol. Testes anteriores estavam de acordo com as previsões teóricas com uma precisão de uma parte em mil. A experiência da Cassini melhorou a precisão até cerca de 20 partes em um milhão, com os dados ainda a suportar a teoria de Einstein.

Chegada a Saturno

27 de Fevereiro de 2004 — Uma nova fotografia de alta resolução tirada pela Cassini no dia 9 de Fevereiro foi divulgada. A imagem surpreendeu os cientistas da missão devido ao fato de não ser visível nenhum "fantasma" nos anéis de Saturno. Estas estruturas escuras na secção "B" do anel foram descobertas nas imagens tiradas pela sonda Voyager em 1981.34 Outra imagem, em luz infravermelha, tirada a 16 de Fevereiro mostra diferenças na altura das nuvens.35 A mesma perturbação era visível nas imagens tiradas pelo Telescópio Espacial Hubble nos anos 90 do século XX.
12 de Março de 2004 — Fotografias tiradas a 23 de Fevereiro não mostram uma característica descoberta pela Voyager: espessamentos no exterior do anel "F". Ao tempo, o que não pôde ser deduzido foi o tempo de vida exato destes espessamentos, e espera-se que a Cassini produza dados decisivos sobre esta questão. O primeiro conjunto de imagens mostra um conjunto de espessamentos ao longo do anel "F".36
26 de Março de 2004 — A equipe de cientistas da Cassini publicou a primeira sequência de imagens de Saturno mostrando nuvens a moverem-se em alta velocidade ao redor do planeta. Usando um filtro para ver melhor o vapor de água no topo da cobertura de nuvens densas, movimentos nas regiões equatorial e sul são claramente visíveis. As imagens foram obtidas entre os dias 15 e 19 de Fevereiro.37
15 de Abril de 2004 — A NASA anunciou que os dois satélites naturais descobertos pela Voyager 1 foram avistados, de novo, pela Cassini em imagens tiradas no dia 10 de Março: Prometheus e Pandora. Estes não são satélites comuns, pois o seu efeito gravitacional no anel 'F' levou a que os cientistas os chamassem de "satélites pastores". A sua descoberta emocionou os pesquisadores interessados na dinâmica do sistema de anéis, porque as suas órbitas são próximas o suficiente para que elas interajam uma com a outra de uma forma "caótica". Uma das missões da missão será monitorar de perto os movimentos destes corpos.

Entrada no sistema saturniano

18 de Maio de 2004 — A Cassini entrou no sistema saturniano. O efeito gravitacional de Saturno começou a sobrepor-se à influência do Sol.
20 de Maio de 2004 — Foi divulgada a primeira imagem de Titan. Foi feita a 5 de Maio a uma distância de 29,3 milhões de quilômetros.38
11 de Junho de 2004 — A Cassini sobrevoa o satélite natural Phoebe às 19:33 UT a 2068 quilômetros de distância. Todos os onze instrumentos a bordo operaram como esperado e todos os dados foram adquiridos. Os cientistas planejam usar os dados para criar mapas globais do satélite coberto de crateras e para determinar sua composição, massa e densidade. Vários dias serão necessários para que os cientistas possam rever os dados e chegar a conclusões mais concretas.

Inserção orbital em Saturno e pouso em Titan

1 de Julho de 2004 — A Inserção orbital em Saturno foi efetuada com sucesso, entre os anéis F e G do planeta. Aproximando-se a 19.980 km do topo das nuvens na superfície, fotografias dos anéis foram tiradas e enviadas para os cientistas da missão na Terra.39 Os cientistas surpreenderam-se com a claridade e o detalhes das imagens e vão pesquisá-las durante um bom tempo.
2 de Julho de 2004 — A primeira passagem por Titan foi executada e as primeiras imagens foram enviadas para a Terra. Devido ao plano orbital inicial, a Cassini passou pelo polo sul da lua a uma distância maior que em sobrevoos posteriores. Contudo, durante uma conferência de imprensa a 3 de Junho, os cientistas da missão mostraram imagens que já os forçavam a rever teorias. Agora parece que as características de albedo mais escuro e claro na superfície representam, de fato, materiais diferentes. Ao contrário do esperado, as regiões geladas eram mais escuras que as áreas onde outra matéria (possivelmente orgânica) está misturada com gelo.
16 de agosto de 2004 — Os cientistas anunciam a descoberta de duas novas luas em órbita de Saturno e o sucesso de um dos objetivos do programa: localizar pequenas e desconhecidas luas em volta do planeta. As luas seriam mais tarde batizadas como Methone e Palene.40
25 de dezembro de 2004 — A sonda de pouso Huygens separa-se da Cassini às 02:00 UTC e inicia sua viagem de 22 dias até a atmosfera de Titan.22
14 de Janeiro de 2005 — A Huygens entra na atmosfera de Titan às 09:06 UTC e pousa na sua superfície às 11:35 UTC.2
LEIA MAIS, MUITO MAIS EM 

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Situação atual

A missão Cassini-Huygens chegou a Saturno em julho de 2004 e deveria operar até 2008. Em 15 de abril deste ano, ela recebeu mais fundos do governo para uma prorrogação de dois anos de pesquisas e passou a ser chamada de Missão Cassini Equinox, pois continuaria operacional durante o equinócio em Saturno. Neste período de dois anos, iniciado em 1 de julho de 2010, a Cassini pôde realizar mais 60 órbitas de Saturno, 21 sobrevoos próximos de Titan, sete de Enceladus, seis de Mimas, sete de Tethys, e um sobre DioneRhea eHelene.5

Ao fim do segundo período de operações, a missão recebeu nova prorrogação, desta vez de cerca de sete anos, agora com o nome de Missão Cassini Solstice, até 2017, quando será a época do solstício de verão no hemisfério norte do planeta. Desde então ela vem realizando e realizará 155 órbitas em Saturno, 55 sobrevoos de Titan e 11 de Enceladus.55 A missão deverá se encerrar definitivamente no primeiro semestre de 2017, quando a espaçonave, depois de uma órbita a apenas 3000 km da superfície de Saturno, deverá ser direcionada para um mergulho na atmosfera do planeta, sendo destruída.A missão Cassini-Huygens chegou a Saturno em julho de 2004 e deveria operar até 2008. Em 15 de abril deste ano, ela recebeu mais fundos do governo para uma prorrogação de dois anos de pesquisas e passou a ser chamada de Missão Cassini Equinox, pois continuaria operacional durante o equinócio em Saturno. Neste período de dois anos, iniciado em 1 de julho de 2010, a Cassini pôde realizar mais 60 órbitas de Saturno, 21 sobrevoos próximos de Titan, sete de Enceladus, seis de Mimas, sete de Tethys, e um sobre DioneRhea eHelene.54

LEIA MAIS, MUITO MAIS EM





https://www.youtube.com/watch?v=6JHv4FX0RP4





http://www.nasa.gov/mission_pages/cassini/timeline/index.html

Cassini Timeline

2015 Saturn Tour Highlights:

Dates listed in Spacecraft Event Time (SCET) -- the time the something happens at the spacecraft based on Coordinated Universal Time (UTC).
Click here for details about time conversions.
After a couple of years at high inclination, Cassini returns to a near equatorial orbit in 2015. This will provide new opportunities to fly by Saturn's icy moons again -- including a daring flyby through Enceladus' plumes. Timed to coincide with the plumes' maximum output -- a first for the mission -- this flyby will see Cassini pass a mere 30 miles (48 kilometers) above the moon's surface. Cassini will also fly by Dione twice this year -- the last two of five close flybys in the mission.
Jan 11 – Titan flyby (603 miles, or 970 kilometers) – T-108
During this flyby, RADAR will obtain altimetry on Punga Mare, meaning Cassini will have provided depth and/or composition information on all three of Titan's seas. RADAR will also make a synthetic aperture radar (SAR) observation of the area where a “magic island” has been observed in Ligea Mare. This is a highly dynamic feature first seen in July 2013. By August 2014, the feature’s appearance had changed dramatically.
Feb. 12 – Titan flyby (746 miles, or 1,200 kilometers) – T-109
The visible and infrared mapping spectrometer (VIMS) will use its “push broom” mode to take a high-resolution swath across Titan's north pole region. The instrument will also image the southern hemisphere to view the evolution of Titan's south polar vortex. Cassini's cameras will image Titan's surface and atmosphere over the equatorial sub-Saturnian hemisphere, including northern Tsegihi and eastern Aztlan.
Mar. 16 – Titan flyby (1,414 miles, or 2,275 kilometers) – T-110
Closest approach science consists of a unique, high resolution VIMS regional map of Titan's north polar lakes. VIMS will also acquire a high-resolution mosaic (at less than 3 miles [5 kilometers] per pixel) of part of the north polar area to look for changes with summer solstice. Cassini will also obtain gravity data using its low gain antenna,contributing to our understanding of Titan’s interior structure.
May 7 -- Titan flyby (1,691 miles, or 2,722 kilometers) – T-111
The VIMS instrument will construct a mosaic of Titan's Xanadu region at a resolution of 6 miles (10 kilometers) per pixel. VIMS will also obtain high-resolution images of the impact crater named Minerva at closest approach. The composite infrared spectrometer (CIRS) will conduct limb sounding in the far-infrared to provide insight into the formation of Titan's southern winter polar vortex, as well as obtaining information about the thermal structure and composition of the stratosphere. Cassini's cameras will obtain images of Titan's surface and atmosphere, including eastern Shangri-La and western Xanadu.
June 16 -- Dione flyby (321 miles, or 516 kilometers) – D-4
During this flyby, Cassini’s cameras will map the sub-Saturn part of the trailing side of Dione (i.e., the quarter of the moon's trailing hemisphere that faces Saturn). This observation includes the tectonically deformed terrain named "Eurotas Chasmata," first observed 35 years ago as bright, wispy streaks by the Voyager mission. Cassini will also try to detect fine particles that may be emitted from Dione and determine their composition. The radio science team will use this flyby to improve our knowledge of Dione’s gravitational field, internal structure and the rigidity of its outer ice shell.
July 7 – Titan flyby (6,806 miles, or 10,953 kilometers) – T-112
The CIRS instrument will perform back-to-back limb sounding observations at closest approach, reaching high northern and southern latitudes to contrast the temperatures and gas abundances at the summer and winter poles. VIMS will acquire a mosaic of the sub-Saturn tropical zone that includes the dune fields of Fensal and Aztlan and the Quivira plateau. VIMS will also observe the evolution of the south polar vortex and will look for the formation of clouds at northern mid-latitudes. Outbound, VIMS will take images of the north polar area with the seas illuminated.
Aug. 17 – Dione flyby (295 miles, or 474 kilometers) – D-5
This is the final targeted flyby of Dione in Cassini's long mission. The radio science team will conduct a gravity experiment at closest approach. The data collected will contribute to our knowledge of the internal structure of Dione, the rigidity of its outer ice shell, and enable insightful comparisons with Saturn’s other icy moons.
Sept. 28 – Titan flyby (644 miles, or 1,036 kilometers) T-113
This flyby will provide important observations about the interaction between Titan's ionosphere and the neutral atmosphere with Titan in a sparsely sampled region of Saturn's magnetosphere. The data will provide important information on how Titan interacts with Saturn's magnetosphere. The ion and neutral mass spectrometer (INMS) will sample Titan’s neutral atmosphere and ionosphere. At high altitude above Titan, INMS will observe ions flowing out from Titan's extended outer atmosphere. At the lower altitudes around closest approach, RADAR will study the eastern portion of the Xanadu region.
Oct. 14 – Enceladus flyby (1,142 miles, or 1,839 kilometers) – E-20
During this flyby, Cassini will image the north polar regions of Enceladus -- something not possible in the first years of the mission, when the moon's north was in darkness. Scientists are eager to search for indications of whether the north polar region might have been geophysically active at some time in the past. There are also two plume observations designed to allow scientists to better understand the connection of specific jets to surface hot spots, and to search for variability in the plumes.
Oct. 28 – Enceladus flyby (30 miles, or 49 kilometers) – E21
This daring flyby will bring the spacecraft within 30 miles (48 kilometers) of Enceladus’ south pole. The flyby is timed to occur when the moon’s plumes are at their maximum output -- a first for the mission. This will allow Cassini to obtain the most accurate measurements yet of the plume's composition.
Nov. 13 – Titan flyby (7,407 miles, or 11,920 kilometers) – T-114
Near closest approach, Cassini's imaging cameras will acquire a medium-to-high-resolution mosaic of Titan's leading hemisphere over Xanadu. Other observations on this flyby include VIMS' monitoring of the formation and evolution of clouds at high latitudes and the evolution of south polar vortex. VIMS will map the north pole area at high emission angles, and will monitor the evolution of the lakes and seas. CIRS will perform very high-latitude limb sounding over the south pole, monitoring the temperatures and composition in the south polar vortex as it continues to develop in southern fall. The latitudes viewed during this flyby are the most southerly latitudes possible for far-infrared limb measurements during this phase of the Cassini mission.
Dec. 6 – Protective measures to ensure safe passage through an area of increased ring particle concentration. Cassini will be turned so that its high gain antenna can be used like umbrella to shield the spacecraft from impacts by ring particles.
Dec. 19 – Enceladus flyby (3,106 miles, or 4,999 kilometers) – E-22
This will be the last targeted Enceladus flyby of the mission. The CIRS instrument will observe the moon's south polar terrain. By the time the mission concludes on 2017, Cassini will have obtained observations over six years of winter darkness in the moon's southern hemisphere. These are ideal conditions for improving measurements of heat flow from the interior to the surface. Understanding heat flow is important because it provides key information on what is driving the geysers.

http://www.nasa.gov/mission_pages/cassini/timeline/index.html



http://saturn.jpl.nasa.gov/mission/saturntourdates/


2016 Saturn Tour Highlights:
Dates are listed in Spacecraft Event Time (SCET) -- the time the something happens at the spacecraft based on Coordinated Universal Time (UTC). Click here for details about time conversions.
Click here for a more complete list of the planned tour dates in 2016.



After a year of touring the Saturn system nearly in the equatorial plane, Cassini bid goodbye to its final close encounters with Saturn’s smaller satellites in 2015, including three spectacular flybys of Enceladus. In 2016, 11 Titan flybys punctuated by a handful of large main engine burns will raise Cassini’s inclination to almost 64 degrees. This will set up the 20 F-ring orbits and prepare for the spacecraft's Grand Finale mission phase beginning in April 2017.


Along the way, the Optical Remote Sensing, RADAR, Radio Science, and Ion and Neutral Mass Spectrometer (INMS) will make full use of the Titan flybys to further explore this mysterious world. The smaller satellites are not completely ignored but the encounters will be much more distant. After T125, Cassini’s emphasis will begin to shift to Saturn and its rings as the spacecraft gets some of the closest views since Saturn Orbit Insertion in 2004.



January 16: Titan flyby (2,372 miles, or 3,817 kilometers)—T-115: The Composite Infrared Spectrometer (CIRS) will perform limb mapping on both the north and south limbs of Titan on the same flyby which will provide a comparison and contrast between the spring (north) and fall (south) hemispheres where rapid changes in atmospheric circulation are occurring. This is one of the two most scientifically important Titan flybys in the Solstice mission for CIRS. Limb mapping provides a measure of how the gas and aerosol abundances vary with altitude; CIRS will also measure temperature profiles and potentially infer the locations of cloud layers.


February 1: Titan flyby (870 miles, or 1400 kilometers) —T-116: UVIS stellar occultations of Epsilon Orionis and Zeta Orionis sample Titan’s atmosphere from roughly 15 – 40 º N. UVIS solar occultations probe both northern and southern latitudes. Occultations are of especially high value because they provide detailed vertical profiles of composition and temperature in the high atmosphere, not accessible by any other instrument and also not by UVIS from reflected sunlight. The solar occultation is also observed by VIMS and provides detailed vertical profiles of composition and aerosols in the atmosphere below 200 km.


February 16: Titan flyby (633 miles, or 1018 kilometers) —T-117: An RSS occultation in Titan’s northern hemisphere (latitudes of ~7S and ~30N degrees,) will profile the thermal structure of the atmosphere. The occultation is followed by a short-duration high northern-latitude egress-only bistatic scattering with a ground track likely crossing small lakes, covering the region from about (80N, 190W) to about (70N, 240W) degrees, and capturing near-grazing scattering angle decreasing from about 80 to 75 degrees. . Data from this observation may yield information about surface reflectivity, dielectric constant, and roughness.


March 11: Enceladus will pass in front of a star while Cassini’s Ultraviolet Imaging Spectrometer will be carefully measuring how the light from the star decreases as it passes behind the moon’s plume. Scientists will measure the density, velocity, and composition of the plume from these measurements, and try to map out its shape and understand how it is changing with time.


April 4: Titan flyby (615 miles, or 990 kilometers)—T-118: This is the only flyby in the mission where UVIS and INMS will observe Titan's atmosphere simultaneously at the same latitude. UVIS will sample remotely by observing the solar occultation signal and INMS will sample the upper atmospheric density directly. Early comparisons of atmospheric density made at different latitudes and times were difficult to reconcile. The UVIS occultations are near North & South polar vortex boundaries; unusual patterns of gas abundances and temperature are seen in these regions in the south. Both hemispheres are interesting because they sample a dynamical regime that is not typical of the rest of Titan's atmosphere.


May 6: Titan flyby (603 miles, or 971 kilometers)—T-119: RSS observes a mid-northern latitude atmospheric occultation to profile the thermal structure of the atmosphere and its possible seasonal variation. RSS continues with a short (~ 1hr) high northern latitude bistatic scattering observation with a ground track possibly crossing small lakes. Data from this observation may yield information about surface reflectivity, dielectric constant, and roughness. INMS gathers data at closest approach. This is the only time in the mission that INMS will have the chance to measure Titan’s atmosphere in this geometry: when Titan’s nightside atmosphere is receiving the smallest possible infusion of external energy. MIMI, standing in for the CAPS instrument, will measure the energetic ion and electron environment to estimate the energetic particle input to Titan’s atmosphere and ionosphere, which will help interpret the ionization layers and scale heights observed by RSS.


June 7: Titan flyby (606 miles, or 975 kilometers)—T-120: Near closest approach, RADAR will conduct SAR imaging (and global shape via SAR topo) of Titan’s poorly-covered southeastern quadrant, producing a map of Titan’s cloud-covered surface. This will be the last high southern latitude SAR coverage of the mission. The ridealong SAR on INMS covers Shangri-La.


July 25: Titan flyby (607 miles, or 976 kilometers) T-121: RADAR carries out prime SAR of Tui Regio and Hotei Arcus to better characterize putative cryovolcanic features and perform change detection, comparing with the T43 and T48 flybys. RADAR will play “switch hitter”, switching from right-look to left-look near closest approach to hit both targets.


August 10: Titan flyby (994 miles, or 1599 kilometers) T-122: The last RSS Titan Gravity flyby of the mission. The main science objectives of gravity measurements at Titan are to 1) assess the presence of a global subsurface ocean by measuring the short-period changes of the gravity field induced by Saturn’s tidal field (eccentricity tides); 2) determine the geoid of the satellite and the presence of large scale gravity anomalies; and 3) determine the rheology of the icy crust by correlative analysis with altimetric data.


September 11: Dione will pass in front of a star while Cassini’s Ultraviolet Imaging Spectrometer will carefully measure if the light from the star is dimmed by an atmosphere or plume, indicating possible activity on the icy moon.


September 27: Titan flyby (1079 miles, or 1736 kilometers) T-123: During this ORS flyby, VIMS will observe the Arcturus occultation that will provide information on the atmospheric composition and its evolution. After the occultation, VIMS will take a high-resolution image of an area on Xanadu. CIRS will make detailed scans of Titan's atmospheric limb near 50N revealing the vertical structure of temperature and trace gas abundances, such as hydrocarbons and nitriles. These data will be used for comparison with observations of equivalent southern latitudes, which are currently experiencing late Fall (south) instead of spring (north). They will also be compared with views of the north earlier in the mission.


November 21: Rhea will pass in front of a star while Cassini’s Ultraviolet Imaging Spectrometer will carefully measure if the light from the star is dimmed by the moon’s very thin atmosphere. This atmosphere is composed of oxygen and carbon dioxide that is formed either by surface chemical reactions or by outgassing, and Cassini scientists hope to more fully characterize it.


November 14: Titan flyby (983 miles, or 1582 kilometers) T-124: RSS bistatic scattering observation, one of two opportunities in the entire mission ideal for capturing potential mirror-like surface echoes from Titan's high northern seas. The ground track covers the surface region close to Titan's North pole, crosses Punga Mare(the first bistatic observation of the feature) and other likely liquid-filled close by regions, and ends over the western part of Kraken Mare, a region not explored before by RSS. These measurements will offer a unique opportunity to compare physical properties of Titan’s three major northern seas, and potential differences among different regions of the vast Kraken Mare.


November 29: Titan flyby (2003 miles, or 3223 kilometers) T-125 VIMS— Gateway to F-Ring orbits and Cassini's Grand Finale mission phase.


December 18: The small moon Pandora, which is only about 50 miles (82 kilometers) in size and orbits right outside Saturn’s main ring system, will make its closest passage to Cassini at a distance of 8600 miles (13,800 kilometers). This heavily battered moon appears to be covered with a fine layer of dust and criss-crossed by enigmatic striations.

http://saturn.jpl.nasa.gov/mission/saturntourdates/


http://www.lpi.usra.edu/opag/march_08_meeting/presentations/spilker.pdf




Cassini Mission 
NASA's Jet Propulsion Laboratory

Cassini spacecraft

Cassini's Superhuman Senses05.26.04 
The Cassini spacecraft is loaded with an array of sophisticated instruments and cameras, to deliver valuable data from the mission to scientists around the world.

Image right: An animation showing the Cassini spacecraft various instruments. + View QuickTime (.8 Mb)
Image credit: NASA/JPL
 




Belíssima Imagem realizada por Amador:

A Gaggle of Moons by Emily Lakdawalla


http://saturn.jpl.nasa.gov/multimedia/images/amateur-image/images/IMG004988.jpg

A Gaggle of Moons by Emily Lakdawalla
February 25, 2014


From the producer, Emily Lakdawalla:
“Cassini caught five moons at the edge of Saturn’s ring system in this natural color photo from July 29, 2011. From left, the moons are Janus, Pandora, Enceladus, Mimas, and Rhea.”
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.


https://www.facebook.com/photo.php?fbid=398019360269874&set=a.398017803603363.90660.398017433603400&type=3&theater





Informações básicas extraídas da Página do Facebook

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    Sobre

    Exploring Saturn system since 2004, the Cassini mission has revolutionized our view of the planet, its rings, and moons. The mission is a cooperative project of NASA, the European Space Agency and the Italian space agency, Agenzia Spaziale Italiana (ASI).
    Missão
    The Cassini program is an international cooperative effort involving NASA, the European Space Agency (ESA) and the Italian space agency, Agenzia Spaziale Italiana (ASI), as well as several separate European academic and industrial contributors. The Cassini partnership represents an undertaking whose scope and cost would not likely be borne by any single nation, but is made possible through shared investment and participation. Through the mission, about 260 scientists from 17 countries hope to gain a better understanding of Saturn, its stunning rings, its magnetosphere, Titan and its other icy moons.
    Descrição
    Cassini completed its initial four-year mission to explore the Saturn System in June 2008 and the first extended mission, called the Cassini Equinox Mission, in September 2010. Now, the healthy spacecraft is seeking to make exciting new discoveries in a second extended mission called the Cassini Solstice Mission.

    The mission’s extension, which goes through September 2017, is named for the Saturnian summer solstice occurring in May 2017. The northern summer solstice marks the beginning of summer in the northern hemisphere and winter in the southern hemisphere. Since Cassini arrived at Saturn just after the planet's northern winter solstice, the extension will allow for the first study of a complete seasonal period.

    Cassini launched in October 1997 with the European Space Agency's Huygens probe. The probe was equipped with six instruments to study Titan, Saturn's largest moon. It landed on Titan's surface on Jan. 14, 2005, and returned spectacular results.

    Meanwhile, Cassini's 12 instruments have returned a daily stream of data from Saturn's system since arriving at Saturn in 2004.

    Among the most important targets of the mission are the moons Titan and Enceladus, as well as some of Saturn’s other icy moons. Towards the end of the mission, Cassini will make closer studies of the planet and its rings.

    More about the mission: http://saturn.jpl.nasa.gov/mission/introduction/
    Informação Geral
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    If you're looking for the official source of information about NASA, please visit our homepage at www.nasa.gov.
    https://www.facebook.com/NASACassini/info




    Crescent Saturn


    Credit: NASA/JPL-Caltech/Space Science Institute



    http://saturn.jpl.nasa.gov/mission/introduction/


    Mission Overview

    Cassini completed its initial four-year mission to explore the Saturn System in June 2008 and the first extended mission, called the Cassini Equinox Mission, in September 2010. Now, the healthy spacecraft is seeking to make exciting new discoveries in a second extended mission called the Cassini Solstice Mission.
    The mission’s extension, which goes through September 2017, is named for the Saturnian summer solstice occurring in May 2017. The northern summer solstice marks the beginning of summer in the northern hemisphere and winter in the southern hemisphere. Since Cassini arrived at Saturn just after the planet's northern winter solstice, the extension will allow for the first study of a complete seasonal period.
    Cassini launched in October 1997 with the European Space Agency's Huygens probe. The probe was equipped with six instruments to study Titan, Saturn's largest moon. It landed on Titan's surface on Jan. 14, 2005, and returned spectacular results.
    Meanwhile, Cassini's 12 instruments have returned a daily stream of data from Saturn's system since arriving at Saturn in 2004.
    Among the most important targets of the mission are the moons Titan and Enceladus, as well as some of Saturn’s other icy moons. Towards the end of the mission, Cassini will make closer studies of the planet and its rings.



    Jewel of the Solar System




    Jewel of the Solar System
    A swing high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings. The view is in natural color, as human eyes would have seen it. This mosaic was made from 36 images in three color filters obtained by Cassini's imaging science subsystem on Oct. 10, 2013. The observation and resulting image mosaic were planned as one of three images for Cassini's 2013 Scientist for a Day essay contest.  
    Saturn sports differently colored bands of weather in this image. For instance, a bright, narrow wave of clouds around 42 degrees north latitude appears to be some of the turbulent aftermath of a giant storm that reached its violent peak in early 2011. The mysterious six-sided weather pattern known as the hexagon is visible around Saturn's north pole.
    When Cassini arrived in 2004, more of the northern hemisphere sported a bluish hue and it was northern winter. The golden tones dominated the southern hemisphere, where it was southern summer. But as the seasons have turned and northern spring is in full swing, the colors have begun to change in each hemisphere as well. Golden tones have started to dominate in the northern hemisphere and the bluish color in the north is now confined to a tighter circle around the north pole. The southern hemisphere has started getting bluer, too.
    The rings shown here include Saturn's main rings. The rings known as the C, B and A rings -- listed here in order of closeness to Saturn -- are easily seen. The F ring is also there, but not easily seen without enhancing the contrast of the image. (Rings were named in order of their discovery rather than their position around Saturn.) The rings also cast a shadow on Saturn at the limb of the planet in the lower right quadrant.
    Cassini is currently in a set of tilted orbits known as "inclined orbits" that allow it to swing up over the north pole and below the south pole. Much of Cassini's time is spent close to the equatorial plane, where most of Saturn's rings and moons are located.
    The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team consists of scientists from the United States, the United Kingdom, France and Germany. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
    For more information about the Cassini-Huygens mission visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.
    Image credit: NASA/JPL-Caltech/SSI/Cornell





    Shadows and Rings


    Credit: NASA/JPL-Caltech/Space Science Institute




    COM UM ABRAÇO ESTRELADO,
    Janine Milward