quarta-feira, 29 de outubro de 2008

Supermassive black holes common in early Universe

BY DR EMILY BALDWIN
ASTRONOMY NOW
Posted: October 17, 2008Observations of a spectacular collision of galaxies in the distant Universe have revealed that colossal black holes were present when galaxies were just beginning to form.
The observations were made with the Submillimeter Array (SMA) in Hawaii, which focuses on wavelengths of 200 microns to 1 millimetre that are most sensitive to the very cold gas and dust associated with the earliest evolutionary stages of stars, galaxies and planets. The SMA can peer into these primordial interstellar clouds and witness the birth of stars. 

This image captures the moment, approximately 12 billion years ago, when the observed galaxy's black hole ripped a stream of dusty gas from a neighbour. Image: STFC.

 

In the new observations galaxy 4C60.07 attracted the attention of astronomers because of its bright radio emission that betrayed the presence of a quasar – a black hole spinning rapidly as it feeds on its parent galaxy. At first, astronomers thought that the gas surrounding the black hole was undergoing a burst of star formation, turning fresh new gas into stars at a rate of about 5,000 of our Suns every year. But the latest research revealed that the stars of 4C60.07 are actually much older than originally perceived. Instead, the star forming factory is located in a previously unknown companion galaxy, which is rich in gas and clouded with dust, and has another colossal black hole residing at its centre.
"This new image reveals two galaxies where we only expected to find one," says Professor Rob Ivison, lead author of the study that will be published in the Monthly Notices of the Royal Astronomical Society. "Remarkably, both galaxies contain super-massive black holes. Such monsters are rare and we now suspect that the radio galaxy had only 'turned on' because it is involved in a collision with a previously unknown galaxy, which helps feed its black hole and thus power the radio jets."
The two galaxies – and their central black holes – smashed together in a dramatic collision, but because this cataclysmic event occurred less than two billion years after the big bang, the galaxies will have long since merged, creating a single monstrous black hole. The implications are wide reaching, and the astronomers can't help but wonder how many other colossal black holes may be lurking unseen in the distant Universe.
"We know the black holes we have found are massive because one is powering a pair of staggeringly luminous radio lobes and the other is modifying the whole optical/infrared spectral energy distribution of its parent galaxy," Ivison tells Astronomy Now. "Massive black holes were already known to exist in the early Universe, but these objects are amazingly rare – we can count them on our fingers. Until now, they were thought to be freaks – completely unrepresentative of the general galaxy population. The observations we've presented in this paper show that such massive black holes may be ten-a-penny."
The galaxies hosting the black holes are both about the size of the Milky Way, but each one is unique. "The radio galaxy looks to be more evolved than its neighbour," says Ivison. "It may have used up most of its gas by forming stars and feeding its black hole in the run-up to the collision, possibly hundreds of millions of years earlier. The neighbour is forming thousands of stars in an intense starburst, triggered by the collision, so it is less evolved and clearly has plenty of gas."
The presence of these two giant black holes in both of the galaxies has big implications for their genesis, since supermassive black holes take time to grow and can have a profound influence on the evolution of their parent galaxy, by triggering star formation or even shutting it down completely. Understanding the prevalence of black holes in the early years of the Universe will rely on combining information from across the whole electromagnetic spectrum. The UK's revolutionary new submillimetre camera, SCUBA 2, should play a key role in black hole characterisation and help astronomers to monitor their growth and their host galaxies in much more detail.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Phoenix completes soil deliver

BY DR EMILY BALDWIN
ASTRONOMY NOW
Posted: October 22, 2008
NASA's Phoenix Mars Lander has finished scooping soil samples to deliver to its onboard laboratories, and is now preparing to analyse samples already obtained before the Sun completely sets on the mission.
Last week, the lander's robotic arm successfully delivered soil into oven six of the Thermal and Evolved Gas Analyser (TEGA), a bonus for the mission since the mission goal of filling and examining soil in at least three of the ovens has already been completed.

This image shows four of the eight cells in the TEGA instrument. TEGA's ovens, located underneath the cells, heat soil samples so the released gases can be analysed. Left to the right the cells are numbered 7, 6, 5 and 4, with the most recent delivery to cell 6 Image: NASA/JPL-Caltech/University of Arizona/Max Planck Institute.

The project scientists are keen to analyse the samples as the power Phoenix generates continues to drop as autumn on Mars gradually sets in. "My entire team is working very hard to make use of the power we have before it disappears," says William Boynton, the lead scientist for TEGA. "Every time we fill an oven, we potentially learn more about Mars' geochemistry." TEGA's tiny ovens heat the soil to as high as 1,000 degrees Celsius in order to sniff out the gases derived from heating the soil.
Meanwhile, the spacecraft's robotic arm is digging into the lower portion of the Upper Cupboard and Stone Soup regions of the Phoenix workspace and the Surface Stereoscopic Imager is documenting trenching so scientists can better map out the geology of the ice table already found a few centimetres below the surface. "We're basically trying to understand the depth and extent of the ice table to tie together how geology and climate control its formation," says Phoenix mission scientist Diana Blaney of NASA's Jet Propulsion Laboratory.
Later this week, mission engineers will instruct Phoenix to use its robotic arm to attempt to push a soil sample piled in a funnel on top of the lander's Wet Chemistry Laboratory into a cell for analysis. Images of the soil already captured will be taken using the Optical Microscope. In addition, digital-elevation models of a rock called Sandman are scheduled with Phoenix's Robotic Arm Camera.
Mission scientists will continue to research and analyse the soil samples in the coming months, long after Phoenix stops operating on the surface.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Aqui começou a discórdia

Postado por Cássio Barbosa em 15 de Outubro de 2008 às 10:53
Cá estou eu em mais uma viagem para congresso. Desta vez, vim participar de um encontro para comemorar os 70 anos de um colaborador meu. O congresso está acontecendo no Observatório Lowell, no Arizona (EUA). Além do congresso em si, o local escolhido é bastante interessante, já que este foi o observatório onde Plutão foi descoberto, além de outras coisas. Agora que eu já fiz minha apresentação, modéstia à parte bastante elogiada, estou mais tranqüilo para atualizar o blog.
Tudo começou em 1893, quando Percival Lowell, um diplomata formado em matemática, ouviu dizer que Schiaparelli, o astrônomo italiano que observou os canais de Marte, estava ficando cego e não poderia mais continuar seu trabalho. Em 1894 ele construiu seu observatório no alto de uma colina em Flagstaff. O local foi escolhido depois de intensa pesquisa e se revelou um excelente sítio, muito escuro e muito seco, quase um deserto.
Esse observatório era dedicado ao estudo do Sistema Solar, em especial de Marte e seus canais. De acordo com a teoria de Lowell, os marcianos usavam esses canais para levar água dos pólos para o resto do planeta. Segundo ele, era possível perceber a vegetação crescendo em torno do canal de tempos em tempos. Lowell registrou suas observações em desenhos coloridos (cheguei a manuseá-los em uma biblioteca da USP) e em globos marcianos como este no museu do observatório (que não deu para pegar).
Marte globo
Além de Marte, Lowell também estudou intensivamente Mercúrio (produzindo alguns rascunhos de sua superfície), determinou o período de rotação de Mercúrio e Vênus e determinou a constituição interna de Júpiter e Saturno a partir da observação de seus satélites. Além dos canais marcianos, outra obsessão de Lowell era descobrir o nono planeta do Sistema Solar, que ele chamava de Planeta X.
Para tentar localizá-lo, Lowell partiu do mesmo princípio usado para descobrir Netuno. Depois de descoberto, Urano por vezes se "atrasava" ou se "adiantava" e não era encontrado na posição prevista. O astrônomo inglês John Adams e o matemático francês Urbain Le Verrier (independentemente) modelaram essas pertubações como sendo originárias de um outro planeta e definiram qual deveria ser a sua posição no céu. Aí começou uma corrida para ver quem descobriria o tal planeta até que finalmente Netuno foi observado em 23 de setembro de 1846 por James Challis. Essa história tem detalhes que envolvem desleixo, competição e coincidências que outra hora eu conto, mas Galileu já tinha observado Netuno em dezembro de 1612 e janeiro de 1613. No entanto, como o planeta tem um movimento muito lento no céu, Galileu não percebeu nenhuma mudança em sua posição, de modo que o confundiu com uma estrela.
Voltando ao Planeta X, Lowell tentou aplicar o mesmo raciocínio para Netuno, que teimava em não estar na posição prevista. Hoje sabemos que essas perturbações são ocasionadas pelos outros planetas gigantes do Sistema Solar e não poderiam ser criadas por um corpo celeste tão pequeno como Plutão. Em 1915, é possível que Lowell tenha feito algumas fotos de Plutão, que teria passado despercebido. Depois de sua morte, em 1916, apenas em 1929 a busca pelo Planeta X foi retomada por Clyde Tombaugh. Finalmente, em 1930, Plutão foi descoberto nesse aparelho da foto abaixo. Ele é um comparador de campos e funciona de modo simples: uma foto de uma determinada região do céu era tirada e, após duas semanas, tirava-se outra foto dessa mesma região. As duas eram colocadas lado a lado e iluminadas alternadamente. Se alguma coisa mudasse de uma imagem para outra, estaria ali um corpo do Sistema Solar, já que as estrelas não se mexem.
Piscadela
Quase 100 anos depois, Plutão foi rebaixado à categoria de planeta anão, mas aparentemente essa história não terminou. Na assembléia geral da União Astronômica Intenacional do ano que vem, que vai acontecer no Rio de Janeiro, essa decisão deve ser rediscutida. Na porta do museu do observatório, quatro urnas estão penduradas e o visitante pode votar nas seguintes opções: "Plutão deve ser considerado um planeta", "Plutão deve ser considerado um planeta anão", "Plutão não deve ser considerado nenhum tipo de planeta" ou "Quem se importa? Eu quero ajudar a manter o observatório!". A votação é feita com cédulas de dinheiro, em forma de doações. Para minha surpresa, planeta anão está ganhando com 320 dólares, contra 226 para planeta.
 
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Nasa lança sonda Ibex para explorar os confins do Sistema Solar

Publicidade da France Presse, em Washington
A Nasa lançou neste domingo a sonda Ibex, cuja missão de dois anos tem o objetivo de obter imagens e mapear os misteriosos confins do Sistema Solar, onde começa, a dezenas de bilhões de quilômetros da Terra, o espaço interestelar.
A sonda foi lançada às 15h45 no horário de Brasília, segundo a agência espacial.
A Ibex (Interstellar Boundary Explorer) está dotada de instrumentos que a permitirão obter imagens e estabelecer a primeira cartografia dessa vasta zona de turbulências e campos magnéticos mesclados, onde as partículas dos ventos solares quentes se chocam com as partículas interestelares de outras estrelas da Via Láctea.
"As regiões fronteiriças do espaço interestelar são essenciais porque nos protegem da maioria dos raios galácticos mais perigosos", disse David McComas, diretor científico da missão.
"Sem a zona, os raios penetrariam na órbita terrestre tornando os vôos orbitais humanos muito mais perigosos", acrescentou McComas.
As únicas informações das quais os cientistas dispõem sobre os confins do Sistema Solar foram dadas pelas sondas Voyager 1 e Voyager 2, lançadas em 1977 e ainda em operação.
A sonda Ibex foi lançada a bordo de um foguete Pegasus que, por sua vez, foi lançado de um tri-reator Lockheed L-1011 voando a 12 mil metros sobre as Ilhas Marshall no Oceano Pacífico.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

A crise em Marte… ou talvez não

 


A crise em Marte… ou talvez não

2008-10-17

Imagem de artista comparando o tamanho do Mars Science Laboratory com um dos rovers actualmente em Marte. Crédito: NASA/JPL-Caltech.
Há uns meses atrás (Abril) já aqui tínhamos alertado para os problemas que o Mars Science Laboratory (MSL), o novo rover marciano da NASA – com lançamento previsto para 2009 – estava a enfrentar. Basicamente, os custos tinham excedido largamente as previsões, e era preciso mais dinheiro. Muito dinheiro: uns 200 milhões de dólares. E claro que havia problemas técnicos na génese dessa necessidade. Porém, essa perspectiva parecia difícil de satisfazer – mesmo antes do recente agudizar da crise económica mundial. Agora, a notícia surgiu perante o grande público, e fala-se abertamente do adiamento da missão para 2011… o que, aliás, só aumentaria os custos. Portanto, pode-se dizer que haverá com toda a certeza um esforço importante para levar a missão para a rampa de lançamento a tempo e horas de aproveitar a janela que se abre em Outubro de 2009.

Apesar do clima de incerteza, nada leva a pensar que a exploração de Marte vá sofrer uma interrupção. No início do ano, o programa americano esteve sujeito a fortes críticas do então director de ciência da NASA – que, entretanto, se demitiu, fazendo a comunidade "marciana" soltar um suspiro colectivo de alívio. E já se sabe que em 2013 a NASA avançará com mais uma sonda orbital. Este novo satélite marciano, MAVEN (Mars Atmosphere and Volatile Evolution Mission), terá como objectivo principal o estudo da atmosfera marciana e da sua evolução, sobretudo dos processos que têm levado à perda de parte substancial desse envelope gasoso ao longo da história do planeta. Espera-se também que nesse mesmo ano seja finalmente enviado para Marte o rover europeu ExoMars, capaz de investigar quaisquer indícios de vida que lhe surjam à frente dos instrumentos.

Para 2016, os americanos estudam o envio de outro rover, mais pequeno que o MSL, ou seja, das dimensões dos actuais MER (Spirit e Opportunity). O papel que lhe seria atribuído seria, para lá da exploração detalhada de uma área interessante (passado com água, potencial para instalação de uma base humana futura), testar algumas tecnologias com vista à futura missão MSR – Mars Sample Return, a executar muito provavelmente na década de 20, e para a qual se procura uma vasta cooperação internacional. É verdade que falta muito tempo, mas os problemas que se colocam a uma missão desse género são também muito grandes, desde a recolha, preparação e acondicionamento de amostras de rochas e solo marcianos até ao seu envio, recepção e armazenamento na Terra. Trata-se porém de um passo fundamental na compreensão da história do planeta vermelho, e uma pedra basilar dos programas de exploração americano e europeu, quer se dê uma (desejável) convergência entre eles ou não. Só depois disso se poderá começar a falar seriamente de missões tripuladas… um sonho que está ainda a décadas da realização.

Embora haja quem afirme que poderia ser feito em menos de 10 anos. Mas essa é uma história para outra ocasião.

     
 
 

Apoios:


© NUCLIO - Núcleo Interactivo de Astronomia 2001-2006

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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Mars orbiter reveals rare polar impact craters

UNIVERSITY OF ARIZONA NEWS RELEASE
Posted: October 15, 2008

An odd, solitary hill rising part-way down an eroding slope in Mars' north polar layered terrain may be the remnant of a buried impact crater, suggests a University of Arizona planetary scientist who studied the feature in a new, detailed image from the HiRISE camera onboard NASA's Mars Reconnaissance Orbiter.


HiRISE found this odd, solitary hill part-way down an exposed section of Mars' north polar layered deposits. Credit: NASA/JPL-Calech/University of Arizona
HiRISE, or the High Resolution Imaging Science Experiment, headed by Alfred McEwen of the Lunar and Planetary Laboratory, is based at the UA. New HiRISE images are posted weekly on the team's Web site.

The north polar layered deposits are stacked up to several kilometers thick and represent one of the largest surface reservoirs of Martian water that interacts with the planet's atmosphere, said LPL's Shane Byrne. Scientists believe the deposits record orbitally driven climate changes and study them to learn how Mars climate evolved.

The new HiRISE image shows an exposed 500-meter thick section (1,640 feet) of this layering, and also a 40-meter high (130-foot) conical mound sticking out of the slope.

"The mound may be the remnant of a buried impact crater, which is now being exhumed," Byrne said. Impact craters would have been buried by ice as the layered deposits accumulated, with layers wrapping around the crater, Byrne said. Almost none exist on the surface of this terrain.

"But in this rare case, erosion formed a trough that uncovered one of these structures. For reasons that are poorly understood right now, the ice beneath the site of the crater is more resistant to this erosion, so that as this trough formed, ice beneath the old impact site remained, forming this isolated hill."

Viewing the HiRISE image at full resolution shows that the mound is made up of polygonal blocks as big as 10 meters, or 33 feet, across, he added. The blocks are covered with reddish dust, but otherwise resemble ice-rich blocks seen in other images of the north polar layered deposits.

The seven new HiRISE images released today include another image of an impact crater where such features are rarely seen -- on the north polar cap. HiRISE turned up a small crater, only about 115 meters, or 125 yards, in diameter on the surface of Planum Boreum, popularly known as the north polar cap.


HiRISE found a rare, small impact crater on Planum Boreum. Credit: NASA/JPL-Calech/University of Arizona
The dearth of craters has led scientists to suggest that either the north polar cap is only about 100,000 years old or that crater impacts into the ice disappear as the ice relaxes, just as imperfections disappear as old window glass relaxes.

Color in the enhanced-color version of the Planum Boreum impact crater comes from dust and from ice of various grain sizes. Blueish ice has a larger grain size than the ice that has collected in the crater. Dust is reddish. A smooth area stretching away from the crater to the upper right of the image may be caused by winds around the crater or by fine-grained ice and frost blowing out of the crater, HiRISE scientists say.

HiRISE has returned more than 8,200 gigapixel-size images of Mars' surface since the start of its science mission in November 2006. The HiRISE team so far has released a total of about 27 terabytes of data, more than all previous deep space missions combined.

The Mars Reconnaissance Orbiter is managed by the Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems of Denver built the spacecraft. The UA operates the HiRISE camera, built by Ball Aerospace and Technology Corp. of Boulder, Colo.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Rússia anuncia investimento bilionário no setor espacial

Publicidadeda Reuters, em Moscou
A Rússia gastará bilhões de dólares nos próximos três anos a fim de consolidar seu papel de destaque no setor espacial, informou o primeiro-ministro Vladimir Putin nesta terça-feira.
O ex-presidente disse numa reunião do governo que a Rússia, responsável por 40% de todos os lançamentos espaciais, vai destinar mais de US$ 7,68 bilhões do orçamento federal para o desenvolvimento do setor espacial entre 2009 e 2011.
A nave tripulada Soyuz e os veículos de carga Progress têm sido os principais meios de acesso à ISS (Estação Espacial Internacional, na sigla em inglês) desde a explosão do ônibus espacial Columbia, dos EUA, em 2003.
A Nasa (agência espacial dos EUA) pretende aposentar sua frota de ônibus espaciais até 2011.
Putin disse que a Rússia já tem mais de cem satélites e que o número vai crescer. Também deve haver pesquisas geológicas a partir do espaço, controle ambiental e monitoramento dos recursos agrícolas, florestais e hídricos.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

NASA Satellite Spots New Type of Pulsar

 
Artist's concept of pulsar
Clouds of charged particles move along the pulsar's magnetic field lines (blue) and create a lighthouse-like beam of gamma rays (purple) in this illustration. Click image for larger view.
NASA
Astronomers have discovered nearly 1,800 neutron stars. These collapsed cores of massive stars are among the most bizarre denizens of the cosmic zoo, each one packing more than a Sun's worth of mass into a city-sized sphere. But according to the first major published result from NASA's recently launched Fermi Gamma-ray Space Telescope, there could be large numbers lurking out there just waiting to be found.

Almost all known neutron stars are also known as pulsars, because they emit pulsed beams of radio waves or X rays that sweep past Earth like lighthouse beams. But on most occasions, these beams miss Earth, making the neutron star effectively invisible at radio or X-ray wavelengths. But according to some theoretical predictions, a pulsar's gamma-ray beam should be wider than a radio or X-ray beam, making it more likely that its beam would illuminate Earth. The key is to have a gamma-ray satellite sensitive enough to detect these beams, and measure their pulsations.

During the 1990s, NASA's Compton Gamma-Ray Observatory discovered dozens of mysterious gamma-ray-emitting objects in the plane of our Milky Way Galaxy. But Compton lacked the spatial and time resolution to pin down the nature of these sources. Astronomers suspected that some or most of them are neutron stars, but scientists knew that a good fraction of them might be background galaxies or some other type of object.

In just a week of observing during its July commissioning phase, Fermi's primary instrument, the Large Area Telescope (LAT), has resolved any lingering uncertainty about one of these unidentified sources: a bright gamma-ray-emitting object at the center of a supernova remnant known as CTA 1, located about 4,600 light-years from Earth. With the LAT's vastly improved sensitivity and timing capability, it not only detected the source easily, it found that it is pulsing with a frequency of 0.317 second. In other words, the object rotates on its axis 3.17 times per second. Based on this result, and its energy pattern, the object must be a pulsar.

Supernova remnant CTA 1
This map of CTA 1's 21-centimeter radio emission highlights the supernova remnant's expanding shell. The shell is about 1.5° wide, three times the apparent size of a full Moon. The pulsar's position is arrowed. CTA 1 is located in the constellation Cepheus.
NASA / S. Pineault, DRAO
"This is the first pulsar discovered only through gamma-ray pulses. This is an exciting result because it means that a lot of pulsars are hidden," says Fermi science team member Alice Harding (NASA/Goddard Space Flight Center), coauthor of a paper on the discovery that appears in the October 16th issue of Science Express. Harding points out that deep observations of CTA 1 at radio and X-ray wavelengths have yet to reveal any hint of pulsations.

"Fermi is doing exactly what we expected it to do: find all these pulsars in gamma-rays that we don't see in the radio," adds radio astronomer Michael Kramer (University of Manchester, UK), who is not on the discovery team.

Harding predicts that many of the unidentified Compton sources will turn out to be pulsars, and that Fermi will see many new sources that will also be pulsars. Studies of these neutron stars will provide clues that will help astronomers piece together the life cycle of neutron stars, and how pulsars emit their beamed radiation.

Kramer points out another important implication. Neutron stars are born in supernova explosions, but many remnants of these explosions lack neutron stars. "It's great that we will start to populate these previously 'empty' supernova remnants with neutron stars that are now at least detectable at other parts of the spectrum," he says.

The discovery also demonstrates that the $690 million Fermi observatory, formerly known as GLAST, is living up to its billing. The spacecraft and its instruments are performing as expected, and it's 5-year mission of scanning the gamma-ray sky at depths never before possible is just getting started. Says Harding, "This is just the first of many exciting things to come."
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Molten planets could point to exo-Earths

BY DR EMILY BALDWIN
ASTRONOMY NOW
Posted: October 20, 2008
Earth-like planets may be easier to spot than planet-hunters originally thought, since their hot, molten surfaces may exist for tens of millions of years, presenting them as glowing beacons as they orbit their parent stars.
Speaking at the American Astronomical Society's Division for Planetary Sciences meeting last week, MIT planetary scientist Linda Elkins-Tanton spoke of how the 'magma ocean' stage for Earth-sized planets – the period when a new born planet is mostly molten magma and has yet to solidify into a distinct core, mantle and crust – may last for a much longer period of time than previously thought. The research shows that even after the surface magma solidifies, within about five million years, it could stay hot enough to glow brightly in infrared light for tens of millions of years, providing a relatively long window for detectability. "That means we may actually see them elsewhere, as detection systems get better," she says.

It is hoped that the Kepler mission, launching in March 2009, will detect tens of Earth-sized planets orbiting other stars. Image: Image.

One of the biggest challenges for astronomers hoping to detect planets around other stars is the vast difference in brightness between the star and the planet, which shines only by reflecting light from its parent star. But the difference in brightness in infrared wavelengths for a glowing, molten planetary surface would be much less, making the detection more feasible.
According to Elkins-Tanton, the long-lived molten stage of planet formation results from a two-stage process, beginning with the combination of heat generated by the influx of rocks that collide and coalesce to form the planet in the first place, and from radioactive decay in the planet's interior. However, this period is relatively short lived and the planet's surface is expected to solidify quickly within a few hundred thousand years. But in the revised model a secondary upheaval begins, in which heavier iron-rich material that has solidified at the surface begins to sink toward the core, causing other hotter material to rise to the surface. This overturn process, which is a bit like the rise and fall of 'lava' in a lava lamp, extends the period that the planet's surface remains molten to millions of years.
But because the Earth is so dynamic – the process of plate tectonics means the Earth's crust is constantly being destroyed and recreated – there is no material left from that initial epoch that could be studied to test this idea. But by looking at Mars or Mercury, Elkins-Tanton may find the evidence she needs to support her theory, especially since her work leads to specific conclusions about the surface composition of different planets. So the detection of specific minerals on Mercury, for example, which the MESSENGER spacecraft may be able to carry out when it begins its study of the planet in 2011, might offer some support to the theory.

And as planet-hunting techniques improve, the detection of hot young planets glowing brightly in infrared around their parent stars may also be realised. Indeed, the search for rocky, Earthlike planets is the primary goal of the Kepler mission which is currently scheduled for launch in March 2009, so Elkins-Tanton and the rest of the planet-hunting community may not have long to wait.

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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

India's first lunar voyage successfully launched

BY STEPHEN CLARK
SPACEFLIGHT NOW

Posted: October 22, 2008


Credit: ISRO
 
India made the next giant leap in its space program early Wednesday with the launch of the country's first deep space mission, a probe to circle the moon with science gear from India, Europe and the United States.

The 3,042-pound Chandrayaan 1 spacecraft was launched at 0052 GMT Wednesday (8:52 p.m. EDT Tuesday) from the Satish Dhawan Space Center on Sriharikota Island on India's east coast.

The probe flew into space aboard a beefed-up Polar Satellite Launch Vehicle, a 146-foot-tall rocket originally built to haul Earth observation satellites into orbit.

The PSLV flew east from the launch site, propelling the spacecraft to a velocity of more than 20,500 mph and reaching an initial orbit with a high point of 14,205 miles and a low point of 158 miles. The inclination was about 17.9 degrees, according to the Indian Space Research Organization.

"Our baby is on the way to the moon," one engineer said a few minutes after the launch.

Engineers at the Chandrayaan 1 control center near Bangalore reported they had contacted the spacecraft moments after it was deployed from the rocket's fourth stage.

"This is an historic moment as far as India is concerned," said G. Madhavan Nair, ISRO chairman. "It was a remarkable performance by the launch vehicle. Every parameter was on the dot."

Senior ISRO officials spoke to the launch team shortly after the first portion of the mission was declared a success.

"What we have started is a remarkable journey for an Indian spacecraft to go to the moon and try to unravel (its) mysteries," Nair said. "I must take this opportunity to congratulate every one of you who have really contributed to this great success."

The final days before launch were plagued by monsoon rains, but the showers stopped long enough for officials to clear the rocket for launch at dawn Wednesday, Indian time.

"We have been fighting against all odds the past four days," Nair said.

Chandrayaan 1, India's first robotic mission to leave Earth orbit, will fire its own engine up to five times in the next two weeks to gradually reach a 250,000-mile-high orbit taking the spacecraft to the vicinity of the moon.

The probe will fire its engine again Nov. 8 to enter lunar orbit. The burn is scheduled to begin at about 1227 GMT (7:27 a.m. EST) to place Chandrayaan 1 in an oval-shaped parking orbit. That orbit will eventually be lowered to a circular path about 62 miles above the moon.

Plans call for Chandrayaan 1 to release a 64-pound impactor around Nov. 15 for a suicidal nosedive into the moon. The trip from orbit to the lunar surface will take about a half-hour, and the small craft will relay imagery, altitude information and spectral data back to Earth through the Chandrayaan mother ship.

Chandrayaan means "moon craft" in Sanskrit, the ancient language of India.

The $80 million mission is India's answer to a pair of lunar missions launched last year by Japan and China. Both countries' moon orbiters are still collecting imagery and scientific data.

But unlike the Japanese and Chinese missions, India invited large contributions from other nations to put instruments on Chandrayaan 1. Scientists from Europe and the United States answered the call.

More than half of the probe's 11 instruments come from outside India. The European Space Agency spent $8 million to fund three payloads, while NASA provided two more sensors. Bulgarian scientists also contributed a radiation monitor to the mission.

The payloads will be turned on and tested by the end of November before the spacecraft begins an operational mission lasting at least two years, officials said.

Scientists expect data from Chandrayaan 1 to help create the most detailed global chemical map of the moon showing mineral concentrations across the lunar surface. Researchers will also make a three-dimensional terrain map of the moon based on information yielded by the mission.

"We are going to look at the moon slightly differently than the people who are looking at it (now). We're looking at the moon very systematically," said Mylswamy Annadurai, Chandrayaan 1 project director at ISRO. "We're going to make a repository of the whole moon and its contents."

ESA's three instruments come from teams led by scientists in the United Kingdom, Germany and Sweden.

"In an era of renewed interest for the moon on a worldwide scale, the ESA-ISRO collaboration on Chandrayaan 1 is a new opportunity for Europe to expand its competence in lunar science while tightening the long-standing relationship with India - an ever stronger space power," said David Southwood, ESA director of science and robotic exploration.

The ESA-funded X-ray and near-infrared imaging spectrometers, called C1XS and SIR 2, will detect mineral signatures in soil on and just below the lunar surface. Both instruments are based on similar sensors that flew aboard Europe's SMART 1 spacecraft, which was deliberately crashed into the moon in 2006.

"European scientists will have the fantastic opportunity to continue our work on the moon," said Detlef Koschny, ESA's Chandrayaan 1 project scientist.

Europe's instruments aboard Chandrayaan 1 will work closely with other countries' payloads to help fill in the blanks in what scientists know about the moon.

"The Apollo missions went down to the surface, but only in a limited number of spots, whereas Chandrayaan tries to do detailed imaging of the entire sphere of the moon," said Christian Erd, ESA's Chandrayaan 1 project manager.

SARA, the other ESA payload, will observe solar wind particles contacting the moon's surface to study its effects on the top layer of soil.

NASA provided a pair of instruments, the Moon Mineralogy Mapper and the MiniSAR radar, as part of the agency's effort to return to robotic exploration of the moon.

"The opportunity to fly NASA instruments on Chandrayaan 1 undoubtedly will lead to important scientific discoveries," said Michael Griffin, NASA administrator. "This exciting collaboration represents an important next step in what we hope to be a long and mutually beneficial relationship with India in future civil space exploration."

The Moon Mineralogy Mapper, nicknamed M3, is a visual and near-infrared imaging spectrometer designed to plot mineral resources at higher resolutions than any instrument before. M3 scientists from the Jet Propulsion Laboratory hope the device will help them create mineral maps to find science-rich landing sites for future missions.

M3 will also look for direct evidence of pockets of water ice hidden inside craters near the lunar poles. Scientists believe there are frozen water deposits deep within the eternally dark craters due to high concentrations of hydrogen found there on previous missions.

The MiniSAR payload was developed by the Johns Hopkins University Applied Physics Laboratory. The instrument will bounce radar beams off the lunar surface to look for signs of water ice packed inside the walls of deep craters near the moon's poles.

The combination of data from the M3 and MiniSAR instruments will allow researchers to determine how many craters could harbor the frozen water, NASA officials said.

India's indigenous suite of science payloads include a terrain camera designed to take detailed black-and-white pictures of the whole lunar surface. The stereo camera will be able to spot features as small as about 16 feet, according to ISRO.

ISRO scientists also built two spectral imagers, one focusing on near-infrared and another in the X-ray range, to help produce precise global maps of the minerals and soil contents on the moon's surface.

A laser system was also bolted to the spacecraft to determine its altitude above the moon and chart lunar surface topography.

Indian engineers also constructed the moon impact probe.

"It has been the dream of Indian scientists to send a satellite around the moon and then collect more data about the surface features, minerals and so on," Nair said. "That dream is going to come true through this mission."

 

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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Cosmic lens reveals distant galactic violence

Astronomers gained a rare glimpse of the violent assembly of a young galaxy.
Provided by NRAO, Socorro, New Mexico
Cosmic lens
Imaging a distant galaxy using a gravitational lens. Bill Saxton/NRAO/AUI/NSF [View Larger Image]
October 21, 2008
By cleverly unraveling the workings of a natural cosmic lens, astronomers have gained a rare glimpse of the violent assembly of a young galaxy in the early universe. Their new picture suggests that the galaxy has collided with another, feeding a super-massive black hole and triggering a tremendous burst of star formation.

The astronomers used the National Science Foundation's Very Large Array (VLA) radio telescope in Socorro, New Mexico, to look at a galaxy more than 12 billion light-years from Earth, seen as it was when the universe was only about 15 percent of its current age. Between this galaxy and Earth, lies another distant galaxy so perfectly aligned along the line of sight that its gravity bends the light and radio waves from the farther object into a circle, or "Einstein Ring."

This gravitational lens made it possible for the scientists to learn details of the young, distant galaxy that would have been unobtainable otherwise.

"Nature provided us with a magnifying glass to peer into the workings of a nascent galaxy, providing an exciting look at the violent, messy process of building galaxies in the early history of the universe," said Dominik Riechers, who led this project at the Max Planck Institute for Astronomy in Germany and now is a Hubble Fellow at the California Institute of Technology (Caltech) in Pasadena.

The new picture of the distant galaxy, dubbed PSS J2322+1944, shows a massive reservoir of gas, 16,000 light-years in diameter, that contains the raw material for building new stars. A super-massive black hole is voraciously eating material, and new stars are being born at the rate of nearly 700 suns per year. By comparison, our Milky Way Galaxy produces the equivalent of about three to four suns per year.

The black hole appears to be near the edge, rather than at the center, of the giant gas reservoir. Astronomers say this location indicates the galaxy has merged with another.

"This whole picture of massive galaxies and super-massive black holes assembling themselves through major galaxy mergers so early in the universe is a new paradigm in galaxy formation. This gravitationally lensed system allows us to see this process in unprecedented detail," Chris Carilli of the National Radio Astronomy Observatory in Charlottesville, Virginia, said.

In 2003, astronomers studied PSS J2322+1944 and found the Einstein Ring by observing carbon monoxide (CO) molecules emit radio waves. When astronomers see large amounts of CO in a galaxy, they conclude that there also is a large amount of molecular hydrogen present, and thus a large reservoir of fuel for star formation.

In the latest study, scientists painstakingly produced a physical model of the lensing intermediate galaxy. By knowing the galaxy's mass, structure, and orientation, they deduced the details of how it bends light and radio waves from the more-distant galaxy. Then they reconstructed a picture of the distant object. By doing multiple VLA images made at different radio frequencies helped the team measure the motions of the gas in the distant galaxy.

"The lensing galaxy was, in effect, part of our telescope. By projecting backward through the lens, we determined the structure and dynamics of the galaxy behind it," Fabian Walter said of the Max-Planck Institute for Astronomy in Germany.

George Djorgovski of Caltech used the digitized Palomar Observatory Sky Survey to discover PSS J2322+1944. Later radio and optical studies showed it had a huge reservoir of dust and molecular gas and indicated gravitational lensing.

Albert Einstein's General Theory of Relativity predicted gravitational lenses in 1919. In 1936, Einstein showed that a perfectly aligned gravitational lens would produce a circular image, but he felt the chances of actually observing such an object were nearly zero. The first gravitational lens was discovered in 1979, and researchers using the VLA in 1987 discovered the first Einstein Ring.

A claret-colored cloud with a massive heart

A small cluster of stars has been found to be the home of one of the most massive double-star systems known to astronomers.
Provided by ESO, Garching, Germany
Gum 29
Stellar nursery Gum 29. ESO [View Larger Image]
October 21, 2008
A new image released by the European Space Observatory (ESO) shows the amazing intricacies of a vast stellar nursery named Gum 29. In the center, a small cluster of stars — called Westerlund 2 — has been found to be the home of one of the most massive double-star systems known to astronomers.

Gum 29 is a huge region of hydrogen gas. The intense radiation of the hot young stars at its center has stripped the region of its electrons. Astronomers call this an HII (pronounced "H-two") region, and this particularly stunning example stretches out across space for more than 200 light-years. The object is the 29th entry in the catalogue published by Australian astronomer Colin Stanley Gum in 1955.

Embedded deep within the huge, nebulous expanse of Gum 29, the relatively little known cluster of Westerlund 2 is seen clearly in the center of this image. The latest measurements indicate that it lies at a distance of some 6,000 light-years from Earth, placing it towards the outside edge of the Milky Way's Carina spiral. The cluster's distance has been the subject of intense scrutiny in the past as it is one of the parameters needed to understand this intriguing object. Westerlund 2 is very young, too, at 1-2 million years old.

Previous observations have shown that two stars to the bottom right of the cluster are true leviathans. Together they form what is known as a double system. The two stars have masses of 82 and 83 times that of our Sun and rotate around each other in approximately 3.7 days. They are among the most massive stars known to astronomers.

Detailed observations of this intriguing pair also have shown that they are both Wolf-Rayet stars. These are massive stars nearing the end of their lives, expelling vast quantities of material as their final swansong. Observations made in Xrays have shown that streams of material from each star continually collide and create a blaze of X-ray radiation.
 
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Newborn Earth-like planets could be easier to find

MIT NEWS RELEASE
Posted: October 16, 2008

CAMBRIDGE, Mass. -- Hot, young planets may be easier to spot because they stay that way longer than astronomers have thought, according to new work by MIT planetary scientist Linda Elkins-Tanton.

For a few million years after their initial formation, planets like Earth may maintain a hot surface of molten rock that would glow brightly enough to make them stand out as they orbit neighboring stars. Elkins-Tanton, Mitsui Career Development Professor of Geology in the Department of Earth, Atmospheric and Planetary Sciences, says the "magma ocean" stage for Earth-sized planets may last a few million years, much longer than previously estimated. "That means we may actually see them elsewhere, as detection systems get better," she said.

Elkins-Tanton presented her new findings this week at the annual meeting of the American Astronomical Society's Division for Planetary Sciences, being held this year in Ithaca, N.Y. The research shows that even after the surface magma solidifies, within about five million years, it could stay hot enough to glow brightly in infrared light for tens of millions of years, providing a relatively long window for detectability.

The big problem for astronomers hoping to detect planets around other stars is the vast difference in brightness between the star and the planet, which shines only by reflecting light from its parent star. But the difference in brightness in infrared wavelengths for a glowing, molten planetary surface would be much less, making the detection more feasible.

The long duration of the molten stage turns out to be the result of a two-stage process, Elkins-Tanton explained. The initial heating, generated by a combination of radioactivity in the planet's interior and the heat generated by the collision of millions of chunks of rock crashing together to form the planet, actually is quite short-lived: The planet's surface is expected to solidify quickly, within a few hundred thousand years, as originally thought. But then a secondary upheaval begins, in which heavier iron-rich material that has solidified at the surface begins to sink toward the core, causing other hotter material to rise to the surface.

This "overturn" process, it turns out, produces the much-longer-lived molten surface, lasting for millions of years, she said. Because the Earth's crust is so dynamic, there is no material left from that initial epoch that could be studied to test this modelling, she said, but on other planets such as Mars or Mercury there might be early remnant rocks that could be tested. The analysis also leads to specific conclusions about the surface composition of planets, so detection of certain specific minerals on Mercury, for example, which the MESSENGER spacecraft may be able to carry out when it begins its study of the planet in 2011, might support the theory.

In addition, the detection of hot, young planets around other stars, which might become possible over the next several years, might provide another line of evidence to support this conclusion, she said.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

New theory improves understanding of galaxy formation

Study may account for many facets of the satellite population of the Milky Way.
Provided by University of Zurich, Switzerland
Magellanic group
Astronomers have proposed that the Magellanic Clouds were the largest members of a group of dwarf galaxies that entered the Milky Way dark halo not long ago. Image courtesy of University of Zurich [View Larger Image]
October 15, 2008

Astronomers at the University of Zurich have proposed a new theory for the formation of dwarf galaxies. In a paper published in The
Astrophysical Journal
", Elena D'Onghia and George Lake solve several outstanding problems by comparing observed dwarfs to supercomputer simulations of their formation (Astrophysical Journal Letters, Volume 686, Nr. 2, p. L61).

The properties of dwarf galaxies present many challenges. "Ten years ago, my team at the University of Washington found that our cosmological model predicts 30-50 times as many small objects as we see. If the numbers had been nearly equal, that would have been an easy success for the model. If there were none, we might figure out a way to keep any from forming" lead author George Lake said "but at the risk of confusing fairy tales, having 30-50 times fewer dwarfs than predicted presents a 'Goldilock problem'. How do we keep most of
them from forming, but not all?"

The main theory to prevent the formation of luminous dwarfs has been that events in the early universe remove the gas that might have formed stars. The first of these events is the global heating and reionization of the universe that happens within a billion years after the Big Bang. In this theory, the small fraction of dwarfs that form quickly enough escape destruction. "While this is an interesting idea, it doesn't explain why most of the dwarfs have stars that form much later than this" Lake said.

There is also the odd grouping of dwarfs. "Like those of the fairy tale, the dwarfs that we have are 'friendly', they group together both within our galaxy and in nearby associations," co-author Elena D'Onghia said. "One might even think they've seen the movie as seven of them are associated with The Magellanic Clouds, the largest satellites of the Milky Way that are easily seen if you are lucky enough to view the sky from the Southern Hemisphere".

In the past, other researchers have noticed that as galaxies form hierarchically in the universe, many of the pieces come in as groups of small objects. "The critical element of these groups of dwarfs isn't that they are a club, but rather they have a 'dwarf leader' or 'parent'. When events in the early universe expel the gas in the smallest object, the dwarf leader shepherds this gas and allows its small companions to recapture it at later times" D'Onghia said.

Lake and D'Onghia have put all these puzzle pieces together to propose that the Magellanic Clouds were the largest members of a group of dwarf galaxies that entered the Milky Way dark halo not long ago. Seven of the 11 brightest satellite galaxies of our Milky Way were part of this group. New simulations performed at the University of Zurich show that it is typical for dwarf galaxies to form in groups and enter large galaxies at late times. Tidal forces disrupt the group and spread the small population of luminous dwarfs around the Milky Way making the satellite galaxies we observe today.

New measurements by scientists at Harvard University, including Nitya Kallivayalil and Gurtina Besla, indicate that the Magellanic Clouds are moving faster than previously believed and may have entered the Milky Way recently. "The scenario proposed by D'Onghia and Lake fits in well with these observational determinations and may account for many facets of the satellite population of the Milky Way," according to Lars Hernquist of Harvard University.

As well as wrapping up several problems in galaxy formation, their theory makes clear predictions that will be tested rapidly. One such prediction is that isolated dwarf and satellite galaxies will be found to have companions. Since their theory was first circulated, the dwarf galaxy Leo IV was found to have another little Leo V companion in July. The existence of nearby dwarf associations also supports this new theory

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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

NASA launches IBEX mission to outer solar system

This is the beginning of NASA's 2-year mission to study the interactions of hot solar wind colliding with the cold vastness of space and map the boundaries of our solar system.
Provided by NASA, Washington, DC
Pegasus
Pegasus rocket being dropped from the L-1011 aircraft. NASA [View Larger Image]
October 20, 2008
NASA's Interstellar Boundary Explorer (IBEX) mission successfully launched from the Kwajalein Atoll in the Pacific Ocean at 1:47 p.m. EDT, Sunday. IBEX will be the first spacecraft to image and map dynamic interactions taking place in the outer solar system.

The spacecraft separated from the third stage of its Pegasus launch vehicle at 1:53 p.m. and immediately began powering up components necessary to control onboard systems. The operations team is continuing to check out spacecraft sub-systems.

"After a 45-day orbit raising and spacecraft checkout period, the spacecraft will start its exciting science mission," said IBEX Mission Manager Greg Frazier of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Just as an impressionist artist makes an image from countless tiny strokes of paint, IBEX will build an image of the outer boundary of the solar system from impacts on the spacecraft by high-speed particles called energetic neutral atoms. These particles are created in the boundary region when the 1-million miles per hour (1.6-million kilometers per hour) solar wind blows out in all directions from the Sun and plows into the gas of interstellar space. This region shields many of the dangerous cosmic rays that would flood the space around Earth.

"No one has seen an image of the interaction at the edge of our solar system where the solar wind collides with interstellar space," said IBEX Principal Investigator David McComas of the Southwest Research Institute in San Antonio. "We know we're going to be surprised. It's a little like getting the first weather satellite images. Prior to that, you had to infer the global weather patterns from a limited number of local weather stations. But with the weather satellite images, you could see the hurricanes forming and the fronts developing and moving across the country."

 
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Os sons de Marte, por fim

2008-10-11

Visão de artista do Phoenix Mars Lander Crédito:NASA
A bordo da sonda Phoenix, actualmente pousada nos frios confins polares do planeta
planeta
Um planeta é um objecto que se forma no disco que circunda uma estrela em formação e cuja massa é superior à de Plutão (1/500 da massa da Terra) e inferior a 10 vezes a massa de Júpiter. Ao contrário das estrelas, os planetas não produzem luz, apenas reflectem a luz da estrela que orbitam.
vermelho, seguia, entre muitos outros instrumentos científicos, uma pequena câmara, a MARDI (Mars Descent Imager) destinada a recolher imagens durante a descida da sonda para a superfície de Marte.

Devido a questões de gestão informática, e para evitar a ocorrência de quaisquer problemas, essa câmara acabou por não ser utilizada. E portanto o microfone que nela estava incorporado também não foi ligado. Agora que a missão se aproxima do fim, com a chegada do Inverno setentrional a Marte, foi decidido dar a ambos os instrumentos uma oportunidade.

Daqui a uns dias, o microfone (semelhante ao que equipa os telemóveis) será ligado enquanto o braço da sonda estiver a realizar uma operação no solo, de forma a perceber se se consegue escutar alguma coisa. Em caso afirmativo, ele voltará a ser utilizado num período de inactividade da sonda – e talvez oiçamos pela primeira vez o som dos ventos que sopram numa planície a muitos milhões de quilómetros da Terra…
 
 
 
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

Einstein-Obra e personalidade de um gênio

"A imaginação é mais importante que a ciência, porque a ciência é limitada, ao passo que a imaginação abrange o mundo inteiro". ─ A. E.

A mostra "Einstein" revela a maior personalidade do século 20 e suas excepcionais contribuições para a humanidade. Inaugurada dia 24 de setembro de 2008, a exposição ─ que permanecerá aberta até 14 de dezembro de 2008 ─ oferece uma visão ampla sobre o homem por trás da ciência. A mostra exibe também as teorias que revolucionaram o entendimento sobre o Universo e deram origem à física moderna.

A exposição inclui várias atrações ─ além de objetos pessoais do cientista e fac-símiles de seus manuscritos raros ─ como cinema 3D, obras de artistas plásticos inspiradas em Einstein e suas teorias, e palestras e debates sobre os conceitos introduzidos por ele em diversas áreas do conhecimento e seus efeitos no pensamento contemporâneo.

Albert Einstein nasceu em Ulm, na Alemanha, em 14 de março de 1879. Foi humanista e físico, naturalizou-se suíço e posteriomente radicou-se nos Estados Unidos. Tornou-se mundialmente conhecido pelo desenvolvimento da Teoria da Relatividade, e celebrizou-se graças à famosa equação E = mc2, que representa a equivalência entre massa e energia.
 
"O mundo é um lugar perigoso de se viver, não por causa daqueles que fazem o mal, mas por causa daqueles que observam, e deixam o mal acontecer." ─ A. E.
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Lucimary Vargas
Presidente
Observatório Astronômico Monoceros
Além Paraíba-MG-Brasil
observatorio.monoceros@gmail.com

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