❝Os Tambores Vão Tocar Na Aldeia
❝Os tambores vão tocar na aldeia
Pra fazer levantar poeira
Oê-oê-oê - aê-aê-aê
Meu povo! Mothokari vem do Sol!❞
More Posts from Carlosalberthreis and Others
Citizen scientist Rick Lundh created this abstract Jovian artwork using data from the JunoCam imager on NASA’s Juno spacecraft.
Image credits: NASA/JPL-Caltech/SwRI/MSSS/Rick Lundh
Pan, e outras luas como ela, têm um profundo impacto nos anéis de Saturno. Os efeitos podem variar, desde a criação de gaps, a geração de novos pequenos anéis, até o surgimento de ondas verticais acima e abaixo do plano dos anéis. Todos os esses efeitos, produzidos pela gravidade são vistos nessa imagem.
Pan, um satélite de Saturno com 28 km de diâmetro, observado no centro da imagem, mantém o chamado Encke Gap, na sua órbita, mas também ajuda a criar e a formar os estreitos anéis que aparecem no Encke Gap. Dois pequenos anéis apagados nessa imagem, podem ser vistos, abaixo e à direita de Pan.
Muitos satélites, incluindo Pan, criam ondas em pontos distantes nos anéis de Saturno, onde as partículas dos anéis e as luas têm órbitas em ressonância. Muitas dessas ondas são visíveis nessa imagem como agrupamentos estreitos de bandas mais escuras e mais escuras. Estudando essas ondas, podem fornecer informações sobre as condições locais dos anéis.
Essa bela imagem foi feita com a câmera da sonda Cassini apontada na direção do lado não iluminado dos anéis, a cerca de 22 graus abaixo do plano dos anéis. A imagem foi feita na luz visível com a câmera de ângulo estreito da Cassini, no dia 30 de Abril de 2016.
A imagem foi obtida a uma distância de cerca de 373000 quilômetros de Saturno, e com o conjunto Sol-Saturno-Cassini em fase com ângulo de 140 graus. A escala da imagem é de 2 quilômetros por pixel.
A missão Cassini é um projeto cooperativo da NASA, da ESA, e da Agência Espacial Italiana. O Laboratório de Propulsão a Jato, uma divisão do Instituto de Tecnologia da Califórnia, em Pasadena, gerencia a missão para o Science Mission Directorate da NASA em Washington. O módulo orbital e suas duas câmeras de bordo foram desenhadas, desenvolvidas e montadas no JPL. O centro de operações de imageamento fica baseado no Space Science Institute em Boulder, no Colorado.
Para mais informações sobre a missão da Cassini-Huygens, visite http://saturn.jpl.nasa.gov e http://www.nasa.gov/cassini. O site da equipe de imageamento da Cassini é http://ciclops.org.
Fonte:
http://www.nasa.gov/image-feature/jpl/pia20490/pandemonium
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Lua e Terra fotografadas pela Apollo 17 em Dezembro de 1972.
Vacina Sim
A vacina induz o organismo a criar defesas necessárias para neutralizar o vírus em uma eventual contaminação.
"··· É uma falsa equivalência equiparar o risco da vacina ao COVID. É 100.000 vezes mais perigoso não ser vacinado."
#VacinaSim
Other “ solar systems ”. The Milky Way has an average of 200 to 400 billion stars, not all stars have a planet around them, but others could have could have at least one planet around them or even more, could have two, four, eight , or more… now imagine the diversity of these worlds, all this is only in the Milky Way… Do you believe there is life out there?
Image credit: NASA/JPL; Tiago Campante / Peter Devine.
Infográfico mostra os planos científicos da China no espaço. Leia tudo aqui: http://gbtimes.com/china/chinas-space-science-centre-unveils-new-missions-after-breakthrough-year
Science, Technology, Engineering and Math: STEM
Today is College Signing Day and we’re working with the White House to celebrate all graduating seniors and inspire more young people to Reach Higher and enroll in higher education.
Additionally, choosing a degree within a STEM (Science, Math, Engineering and Technology) field enables the United States to remain the global economic and technological leader. We feel that it’s our duty to help inspire the next generation of scientists, technologists, engineers and astronauts.
It’s important that each and every student feels empowered and equipped with the knowledge to solve tough problems, evaluate evidence and analyze information. These are all skills students can learn through studying a subjects in STEM.
College is one of the stepping stones to many careers, including becoming an astronaut! Here are a few of our astronauts on their college graduation day, along with their astronaut portrait.
Astronaut Victor Glover
Undergraduate: California Polytechnic State University Graduate: Air University and Naval Postgraduate School Astronaut Class: 2013
Astronaut Reid Wiseman
Undergraduate: Rensselaer Polytechnic Institute Graduate: Johns hopkins University Astronaut Class: 2009
Astronaut Thomas Marshburn
Undergraduate: Davidson College Graduate: University of Virginia, Wake Forest University and University of Texas medical Branch Astronaut Class: 2004
Astronaut Karen Nyberg
Undergraduate: University of North Dakota Graduate: University of Texas at Austin Astronaut Class: 2000
Astronaut Bob Behnken
Undergraduate: Washington University Graduate: California Institute of Technology Astronaut Class: 2000
Astronaut Peggy Whitson
Undergraduate: Iowa Wesleyan College Graduate: Rice University Astronaut Class: 1996
Astronaut Joseph Acaba
Undergraduate: University of California Graduate: University of Arizona Astronaut Class: 2004
Astronaut Rex Walheim
Undergraduate: University of California, Berkeley Graduate: University of Houston Astronaut Class: 1996
Whether you want to be an astronaut, an engineer or the administrator of NASA, a college education opens a universe of possibilities:
Administrator Charles Bolden
Here, Administrator Bolden wears the jersey of Keenan Reynolds, a scholar athlete who graduates from the Naval Academy this year. His jersey is on its way to the college football hall of fame. Bolden holds a drawing of himself as a midshipman in the Navy.
Deputy Administrator Dava Newman
Deputy Administrator Dava Newman sports her college shirt, along with Lisa Guerra, Technical Assistant to the Associate Administrator. Both women studied aerospace engineering at Notre Dame.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
Are we alone in the universe?
There’s never been a better time to ponder this age-old question. We now know of thousands of exoplanets – planets that orbit stars elsewhere in the universe.
So just how many of these planets could support life?
Scientists from a variety of fields — including astrophysics, Earth science, heliophysics and planetary science — are working on this question. Here are a few of the strategies they’re using to learn more about the habitability of exoplanets.
Squinting at Earth
Even our best telescopic images of exoplanets are still only a few pixels in size. Just how much information can we extract from such limited data? That’s what Earth scientists have been trying to figure out.
One group of scientists has been taking high-resolution images of Earth from our Earth Polychromatic Imaging Camera and ‘degrading’ them in order to match the resolution of our pixelated exoplanet images. From there, they set about a grand process of reverse-engineering: They try to extract as much accurate information as they can from what seems — at first glance — to be a fairly uninformative image.
Credits: NOAA/NASA/DSCOVR
So far, by looking at how Earth’s brightness changes when land versus water is in view, scientists have been able to reverse-engineer Earth’s albedo (the proportion of solar radiation it reflects), its obliquity (the tilt of its axis relative to its orbital plane), its rate of rotation, and even differences between the seasons. All of these factors could potentially influence a planet’s ability to support life.
Avoiding the “Venus Zone”
In life as in science, even bad examples can be instructive. When it comes to habitability, Venus is a bad example indeed: With an average surface temperature of 850 degrees Fahrenheit, an atmosphere filled with sulfuric acid, and surface pressure 90 times stronger than Earth’s, Venus is far from friendly to life as we know it.
The surface of Venus, imaged by Soviet spacecraft Venera 13 in March 1982
Since Earth and Venus are so close in size and yet so different in habitability, scientists are studying the signatures that distinguish Earth from Venus as a tool for differentiating habitable planets from their unfriendly look-alikes.
Using data from our Kepler Space Telescope, scientists are working to define the “Venus Zone,” an area where planetary insolation – the amount of light a given planet receives from its host star – plays a key role in atmospheric erosion and greenhouse gas cycles.
Planets that appear similar to Earth, but are in the Venus Zone of their star, are, we think, unlikely to be able to support life.
Modeling Star-Planet Interactions
When you don’t know one variable in an equation, it can help to plug in a reasonable guess and see how things work out. Scientists used this process to study Proxima b, our closest exoplanet neighbor. We don’t yet know whether Proxima b, which orbits the red dwarf star Proxima Centauri four light-years away, has an atmosphere or a magnetic field like Earth’s. However, we can estimate what would happen if it did.
The scientists started by calculating the radiation emitted by Proxima Centauri based on observations from our Chandra X-ray Observatory. Given that amount of radiation, they estimated how much atmosphere Proxima b would be likely to lose due to ionospheric escape — a process in which the constant outpouring of charged stellar material strips away atmospheric gases.
With the extreme conditions likely to exist at Proxima b, the planet could lose the equivalent of Earth’s entire atmosphere in 100 million years — just a fraction of Proxima b’s 4-billion-year lifetime. Even in the best-case scenario, that much atmospheric mass escapes over 2 billion years. In other words, even if Proxima b did at one point have an atmosphere like Earth, it would likely be long gone by now.
Imagining Mars with a Different Star
We think Mars was once habitable, supporting water and an atmosphere like Earth’s. But over time, it gradually lost its atmosphere – in part because Mars, unlike Earth, doesn’t have a protective magnetic field, so Mars is exposed to much harsher radiation from the Sun’s solar wind.
But as another rocky planet at the edge of our solar system’s habitable zone, Mars provides a useful model for a potentially habitable planet. Data from our Mars Atmosphere and Volatile Evolution, or MAVEN, mission is helping scientists answer the question: How would Mars have evolved if it were orbiting a different kind of star?
Scientists used computer simulations with data from MAVEN to model a Mars-like planet orbiting a hypothetical M-type red dwarf star. The habitable zone of such a star is much closer than the one around our Sun.
Being in the habitable zone that much closer to a star has repercussions. In this imaginary situation, the planet would receive about 5 to 10 times more ultraviolet radiation than the real Mars does, speeding up atmospheric escape to much higher rates and shortening the habitable period for the planet by a factor of about 5 to 20.
These results make clear just how delicate a balance needs to exist for life to flourish. But each of these methods provides a valuable new tool in the multi-faceted search for exoplanet life. Armed with these tools, and bringing to bear a diversity of scientific perspectives, we are better positioned than ever to ask: are we alone?
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
E a descoberta de exoplanetas continua, bem, isso é meio óbvio, aliás, é uma das áreas mais prolíficas da astronomia atualmente em grandes descobertas.
Dessa vez uma equipe internacional de astrônomos detectou 3 exoplanetas num sistema estelar binário formado por estrelas gêmeas.
O sistema estelar HD 133131 está localizado a aproximadamente 163 anos-luz de distância da Terra, é um sistema binário que foi descoberto em 1972, tem uma idade estimada de 9.5 bilhões de anos e é formado por duas estrelas gêmeas, ou seja, de mesmo tipo espectral, e que são também do mesmo tipo espectral que o Sol, G2V.
As estrelas estão separadas por 360 UA.
Tudo isso faz desse sistema, primeiro, o formado por estrelas mais próximas onde foram descobertos exoplanetas, e além disso, ambas as estrelas do sistema possuem planetas.
Uma das estrelas possui dois planetas com massas 0.6 e 1.4 vezes a massa de Júpiter e a outra estrela possui um planetas com uma massa 2.5 vezes a massa de Júpiter, ou seja, todos são planetas gigantes.
Mas esse sistema possui mais características peculiares.
As estrelas desse sistema são classificadas como sendo pobres em metal, ou seja, são formadas principalmente por hidrogênio e hélio, isso é incomum em estrelas que abrigam planetas gigantes, já que a maioria é rica em metal e somente 6 sistemas binários pobres em metal foram encontrados com exoplanetas, o que deixa a descoberta mais intrigante.
Já não bastasse tudo isso, ao estudar o sistema em detalhe, os astrônomos descobriram que as estrelas na verdade, possuem uma pequena diferença química na sua composição, o que deixaria de fazer com que elas fossem gêmeas idênticas, e passassem então a serem classificadas somente como gêmeas.
Essa diferenciação pode indicar que uma estrela pode ter engolido planetas menores ainda em formação e isso alterou sua composição química, levemente.
Essa descoberta marcou também a primeira descoberta feita somente com dados obtidos pelo instrumento Planet Finder Spectrograph, que fica acoplado ao Telescópio Magellan II de 6.5 metros no Observatório de Las Campanas no Chile.
Descobrir um sistema tão único assim é de suma importância para se entender a formação de planetas especialmente em sistemas binários.
Ajudar a montar o quebra cabeça de como o Sistema Solar se formou e de alguma forma ajudar os astrônomos a compreender onde planetas possivelmente habitáveis poderiam ser encontrados.
(via https://www.youtube.com/watch?v=GHMfsc0BFj4)
