(Enceladus, fotografado pela Cassini em 12 de Março de 2008 in http://www.nasa.gov)

Algumas das mais recentes imagens captadas pela sonda Cassini, da NASA, indicam que há géisers na superfície deste satélite Enceladus. Segundo tudo indica, a algumas centenas de metros sob a superfície gelada do satélite existem depósitos de água líquida que alimentam estes géisers. Esta descoberta coloca Enceladus no topo da lista dos locais no Sistema Solar capaz de abrigar vida e deverá reformular os planos de exploração espacial para as próximas décadas...

(Imagem revelando os géisers no Pólo Sul de Enceladus in http://www.nasa.gov)

Sob a superfície do satélite existem condições para que existe vida microbiana - pelo menos - já que calor, água líquida e materiais orgânicos são factores todos aqui presentes, como revelou a sonda Cassini, que encontrou nesses géisers dióxido de carbono, monóxido de carbono, metano, propano, acetileno e formaldeído, compostos nunca antes descobertos em tais concentrações no Sistema Solar, nem em Titã, nem em Europa, nem sequer em Marte sendo que alguns deles, como o metano é geralmente associado a uma prova da existência de vida (ver AQUI).

Os primeiros sinais de que haveria água a escapar-se da crosta de Enceladus surgiram em 2005, sendo agora confirmados pela Cassini durante a sua aproximação de Março, um movimento que tornará a repetir em Agosto e, mais tarde, em Outubro, obtendo então mais elementos sobre estes intrigantes sinais de vida no sistema de Saturno...

E quando haverá uma sonda na superfície de Enceladus, imitando o desafio vencido com tanto sucesso pela sonda europeia Huygens?

Fontes:

http://www.msnbc.msn.com/id/11736311/

http://www.space.com/scienceastronomy/080326-cassini-flyby-update.html

This is really good news. It seems the spacecraft is operating well and is in good shape. There are three instruments that have 'hiccups,' not bad for having been launched ten years ago. There is still propellant available to carry out the maneuvers needed in the next two years. The discoveries and pictures just add to the mountain of questions and lists of items we would like to know more about.

Cassini has been providing data daily for the past four years. While operating costs are involved, chiefly in labor, all the equipment, a not insignificant cost, is working and paid for long ago. It actually saves money keep a mission going that yields scientific value. A second spacecraft can be delayed for some years that would entail much additional cost, a cost that can be avoided for a while by keeping Cassini "on the payroll.". Plus Cassini is a proved success. This also helps ensure more focused and specific missions to Titan and Enceladus at some distant point in the future.

See NASA's news release here: http://saturn.jpl.nasa.gov/news/press-release-details.cfm?newsID=833

NASA's Cassini spacecraft discovered a surprising organic brew erupting in geyser-like fashion from Saturn's moon Enceladus during a close flyby on March 12. Scientists are stunned that this tiny moon is so active, "hot" and teeming with water vapor and organic chemicals.

"Enceladus has got warmth, water and organic chemicals, some of the essential building blocks needed for life," said Dennis Matson, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We have quite a recipe for life on our hands, but we have yet to find the final ingredient, liquid water, but Enceladus is only whetting our appetites for more."

http://www.dailygalaxy.com/my_weblog/2008/03/so-long-and-tha.html

A tablet in the British Museum's cuneiform clay tablet collection has been found to be a Sumerian night log book that records the observation of the asteroid that hit Köfels in Austria. These notes allow the night sky to be identified as in the early morning of 29th June 3123 BC and the trajectory can be determined that of an Aten class asteroid, a little over one kilometre in diameter, that was in a resonant orbit with the earth.

http://www.bris.ac.uk/aerospace/research/dynamicsandsystems/kofels/index.html

Researchers: Asteroid Destroyed Sodom and Gomorrah”)

The tablet, found by Henry Layard in the remains of the library in the royal place at Nineveh in the mid-19th century, is thought to be a 700 B.C. copy of notes made by a Sumerian astronomer watching the night sky.

He referred to the asteroid as a "white stone bowl approaching" and recorded it as it "vigorously swept along."

Using computers to recreate the night sky thousands of years ago, scientists have pinpointed his sighting to shortly before dawn on June 29 in the year 3123 B.C.

About half the symbols on the tablet have survived and half of those refer to the asteroid. The other symbols record the positions of clouds and constellations. In the past 150 years scientists have made five unsuccessful attempts to translate the tablet.

(Also in Daily Galaxy April 1, 2008) as:

The tablet has drawings of constellations inscribed on to it, as well as constellation names. But with modern technology allowing researchers to go back in time to view the night sky on any given day, time or year, a more precise indication of what the tablet has been saying all these years has given proof to the Köfels landslide mystery.

According to the researchers, it refers to the night sky observations of an astronomer, taken just before dawn on the 29^th of June, 3132 BC (by the Julian calendar).

Half of the tablet records planet positions – which allowed the researchers to track the date so precisely – as well as cloud cover; attributes which were similar from night to night. However this particular tablet also records the existence of a large object, large enough to be noted while in space. The astronomer/s made an accurate note of its trajectory relative to the stars.

With an error better than one degree, these measurements match up with an asteroid that would soon impact at Köfels.

The ancient observations hint towards the asteroid being approximately one kilometer in diameter, with an Aten type orbit around the Sun (a class of asteroid that orbit close to the earth that is resonant with the Earth's orbit).

However the existence of this not only proves an asteroid impact, but it explains why there is no impact crater. The asteroid came in at a very low angle of only six degrees, and subsequently clipped a mountain called Gamskogel above the town of Längenfeld, 11 kilometres from Köfels. Thus, the asteroid exploded before it reached its final impact point, travelling the last stretch as a giant fireball about five kilometers in diameter; the same size as the landslide.

http://www.dailygalaxy.com/my_weblog/2008/04/asteroid-impact.html

Using US Very Large Array (VLA) and the UK Jodrell Bank radio telescopes, they are observing the birth process of an entirely new planet.

A large disc of material orbiting HL Tau, a Tauran star 500 light years from us, was recently perturbed by the flyby of XZ Tau - another Taurus-constellation star with a significantly more Xtreme set of initials. Researchers from the Edinburgh Institute of Astronomy theorize that this near miss could have disturbed a region of the disk, causing it to begin gravitationally collapsing. And if there's one thing the existence of our world and everything we see in the sky ever proves, it's that once a clump of matter starts to collapse it tends to keep going.

http://www.dailygalaxy.com/my_weblog/2008/04/birth-of-a-new.html

Enceladus, Saturn's miniature ice moon, is shown below in this enhanced, colorized image spewing out the water laden ice particles like a geyser. The episode is titled "Voyage to the Mystery Moon" and here is the link to the show's web page: Voyage to the Mystery Moon web page. A complete transcript to the entire show is at this link: http://www.pbs.org/wgbh/nova/transcripts/3309_titan.html .

Most of the show is about Titan. There is an interactive flash graphic about the rings of Saturn. The interactive displays the following questions:

1- How old are the rings; 2- How did they form; 3- What are they made of; 4- How many rings are there; 5- How vast are they; 6- Why do they lie in one plane; 7- What makes gaps in the rings; 8- What makes bright bands in the rings; 9- Are there moons within the rings; 10- Do the rings have an atmosphere; and, 11- How did Cassini pass through the rings?

Clicking on a question brings up graphics and a side bar with the explanation posed by the question. NOVA programs always have an associated web site to further the educational value of the show and they are always great sites. This particular site I found very nicely organized and informative especially in view of the recent flybys of Titan and Enceladus made by the Cassini spacecraft. There is also an article about how planets, or in the case of Titan, moons, get and acquire their own atmosphere.

So, I'm about to go take a nap. But first a couple of quick notes, and then a bit from Phil Plait's blog about a recent discovery that is very exciting.

Note one: downloads of the .pdf of Communion of Dreams have crossed 8,200 and downloads of the audio version continue to climb as well. That's exciting.

Note two: heard nothing yet from the agent I mentioned contacting the other day. No surprise - I expect that it will take a month or so to hear from them. But I needed something else to note.

Now, about the news from space . . .

I have written previously about the Cassini probe's 10 year mission to Saturn, and how there have been a lot of great images and information coming back to scientists about that planet and its moons. Information that helps to confirm what we knew when I was first writing Communion (since most of the action of the book takes place on and around Titan.) But there is news which would potentially require me to revise the novel slightly - not about Titan, but about its sibling Enceladus. You may have heard something about this, but I'll go to the Bad Astro Boy himself for the news:

Life’s cauldron may be bubbling underneath Enceladus

A few days ago I wrote about how the Cassini Saturn probe dove through water ice plumes erupting from the surface of the icy moon Enceladus. The pictures were incredible, but it may very well be that the other detectors got the big payoff.

They detected organic compounds in the plumes.

Now remember, organic molecules don’t necessarily mean life. What Cassini detected were heavy carbon-based molecules, including many that are the building blocks for making things like amino acids and other compounds necessary for life as we know it.

Edited to add: Carolyn Porco, imaging team leader for Cassini, says:

[…] it is now unambiguous that the jets emerging from the south polar fractures contain organic materials heavier than simple methane — acetylene, hydrogen cyanide, formaldehyde, propane, etc. — making the sub-surface sources of Enceladus’ dramatic geological activity beyond doubt rich in astrobiologically interesting materials.

Whoa. I mean, *whoa* . Seriously. It ain't life, nor even proof of life - but it is *damned exciting*.

Now, a nap.  All this excitement makes me tired.

Jim Downey

Kuvassa Saturnuksen kuu Enceladus.

NASA arvioi, että Saturnuksen Enceladus -nimisessä kuussa saattaa olla elämää. Arvio perustuu avaruusluotain Cassinin tietoihin siitä, että siellä saattaa olla sulaa vettä, sekä muita elämään edellytettäviä aineksia.

Maaliskuun alussa avaruusluotain tutki geysirmäisiä purkauksia ja havaitsi vesihöyryä, sekä orgaanisia yhdisteitä.

- Enceladuksessa näyttäisi olevan elämän synnyn kolme perusoaa. Orgaanisia yhdisteitä, energiaa ja vettä, sanoi amerikkalainen yliopiston tutkija Larry Esposito.

Lähde: iltalehti.fi

Kiitokset vinkistä TheMagicianille.

Jet Blue. Source: NASA/JPL/Space Science Institute

The Cassini team was stunned to discover the geysers two years ago when the probe made its first flyby of the tiny moon. Then on March 12th, they got another chance to point their science instruments at the billowing plume during another close approach, passing just 120 miles from the surface. This time the optical cameras took a back seat to a suite of spectrographs designed to "taste and smell" what chemicals are present.

The team has just announced the initial science findings. It turns out the jets are mostly water vapor, with some ice crystals mixed in. Also present are methane, carbon dioxide, carbon monoxide, and an abundance of both simple and complex organic chemicals.

Another instrument on board measured the temperatures at the fissures where the geysers erupt from the surface. Turns out it gets up to a hot and balmy -130 degrees Fahrenheit there. OK, that's pretty cold. But it is significantly warmer than the -300 degrees Fahrenheit temperatures elsewhere on that moon. The researchers say some sort of heat source deep within the planet must be at work, and that underground pockets of liquid water very likely exist -- maybe even relatively close to the surface.

So what does it all mean? The moon has water, organic compounds, and a heat source...and that makes it a prime hunting ground for astrobiologists (scientists who look for signs of extraterrestrial life). They don't know at this point if that underground liquid water exists, and they certainly don't know if any sort of microbial life form may be living there. But you can bet they're excited about it!

Cassini will flyby Enceladus again in August.

--Kate Tobin, Senior Producer, CNN Science & Technology

The material encountered by Cassini coming up from the surface of Enceladus was much denser than expected, 20 times more so. Volatile gases, water vapor, carbon dioxide and carbon monoxide were components of the plumes Cassini flew through.

Temperatures measured along the fissures were at least minus 135 degrees Fahrenheit. This seems very cold to me but when one realizes how far from the Sun Enceladus is, its actually considered relatively warm. It's 200 degrees Fahrenheit warmer than other places on Enceladus. Scientists believe these temperatures make it more likely there is water flowing beneath the surface of this moon of Saturn.

Observations indicate that four sources of heat send plumes jumping up from the surface. These individual plumes meet and come together, blending to form one large plume.  Future investigations will look at the sources of the individual plumes and the differences among the fissures.

Cassini was 30 miles from Enceladus at its closest approach during this flyby and 120 miles out when it flew through the plumes. The next flyby is planned for August.

Kobi

Everything has run smoothly and the initial module of Kobi was opened for the first time Friday. The hatch was opened at 7:24 MDT March 15, marking the first time the space station's 15-nation program has full on-orbit participation. Kobi is in a temporary berth at the station, and will likely be moved prior to the arrival of the next portion.

Dextre

Not everything ran smoothly with Mr. Dextre's installation. A power problem prevented its initial deployment. The problem was eventually traced to a flawed cable in the pallet containing the robot during shuttle delivery. Once power from the station was introduced, the robot responded to controls. The cable ended up not being the correct type for the powering system.

Last night's work focused on attaching Dextre's two arms. Work with the arms was temporarily slowed due to stubborn bolts, but things were wrapped up by 12:57 MDT this morning. Initial tests of Dextre and it's two arms indicate a nominally operative piece of equipment, which is excellent news.

Cassini

I wrote a post a few days ago regarding Cassini's planned fly-through and testing of Encaladus' eruptive geyser. Unfortunately, a software glitch prevented instrument from determining the make-up of the geyser material during the fly-through. The good news is that cameras were operating at the critical time. They discovered that the north pole of Enceladus appears much older than the moon's south pole.

All is not lost with regard to determining the make-up of the ejecta. NASA officials said that Cassini's Wednesday flyby is the first of four close-up swings past the moon this year. A similar plume pass is slated for October 9th.

And that's just Enceladus. Cassini continues to probe the remainder of the Saturnian system.

Esta é a imagem com maior resolução até hoje da região polar norte da Encélado, uma das luas de Saturno. A sonda Cassini fez a foto a uma distância de 35.000 quilômetros do satélite. (Foto: Nasa)

Cassini Flies Through Watery Plumes of Saturn Moon

NASA's Cassini spacecraft performed a daring flyby of Saturn's moon Enceladus on Wed., March 12, flying about 15 kilometers per second (32,000 mph) through icy water geyser-like jets. The spacecraft snatched up precious samples that might point to a water ocean or organics inside the little moon.

Scientists believe the geysers could provide evidence that liquid water is trapped under the icy crust of Enceladus. The geysers emanate from fractures running along the moon's south pole, spewing out water vapor at approximately 400 meters per second (800 mph).

The new data provide a much more detailed look at the fractures that modify the surface and will give a significantly improved comparison between the geologic history of the moon's north pole and south pole.

New images show that compared to much of the southern hemisphere on Enceladus--the south polar region in particular--the north polar region is much older and pitted with craters of various sizes. These craters are captured at different stages of disruption and alteration by tectonic activity, and probably from past heating from below. Many of the craters seem sliced by small parallel cracks that appear to be ubiquitous throughout the old cratered terrains on Enceladus.

"These new images are showing us in great detail how the moon's north pole differs from the south, an important comparison for working out the moon's obviously complex geological history," said Carolyn Porco, Cassini imaging team leader, Space Science Institute, Boulder, Colo. "And the success of yesterday's daring and very low-altitude flyby means this coming summer's very close encounter, when we get exquisitely detailed images of the surface sources of Enceladus' south polar jets, should be an exciting 'next big step' in understanding just how the jets are powered."

This week's flyby and another one planned for Oct. 9, 2008, were designed so that Cassini's particle analyzers could dissect the "body" of the plume for information on the density, size, composition and speed of the particles. Among other things, scientists will use the data gathered this week to figure out whether the gases from the plume match the gases that make up the halo of particles around Enceladus. This may help determine how the plumes formed.

During Cassini's closest approach, two instruments were collecting data--the Cosmic Dust Analyzer and the Ion and Neutral Mass Spectrometer. An unexplained software hiccup with Cassini's Cosmic Dust Analyzer instrument prevented it from collecting any data during closest approach, although the instrument did get data before and after the approach. During the flyby, the instrument was switching between two versions of software programs. The new version was designed to increase the ability to count particle hits by several hundred hits per second. The other four fields and particles instruments on the spacecraft, in addition to the ion and neutral mass spectrometer, did capture all of their data, which will complement the overall composition studies and elucidate the unique plume environment of Enceladus.

Cassini's instruments discovered evidence for the geyser-like jets on Enceladus in 2005, finding that the continuous eruptions of ice water create a gigantic halo of ice dust and gas around Enceladus, which helps supply material to Saturn's E-ring.

This was the first of four Cassini flybys of Enceladus this year. During Wednesday's flyby, the spacecraft came within 50 kilometers (30 miles) of the surface at closest approach, 200 kilometers (120 miles) while flying through the plume. Future trips may bring Cassini even closer to the surface of Enceladus. Cassini will complete its prime mission, a four-year tour of Saturn, in June. From then on, a proposed extended mission would include seven more Enceladus flybys. The next Enceladus flyby would take place in August of this year.

For more images and more information, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

*****

NASA has invited other nations to place instrumentation in a Lunar Network. To kick off the ILN, NASA would lob on one launcher two small landing packages, one each to the poles of the Moon. The target launch date is 2013-2014. A second pair of U.S. nodes would fly in 2016-2017. Ideally, by year’s end, what nations are joining in on the network, what core instruments are to be flown, and a landing site working group will be agreed to.

*****

It was reported last week that our nearest stellar neighbor, Alpha Centauri, might contain Earth-like planets. From the article:

"Several factors mark the system, particularly Alpha Centauri B as friendly to planet formation, [study co-author Gregory] Laughlin said. The metallicity of Alpha Centauri B (or how much of its matter is made up of elements heavier than hydrogen and helium) is higher than our Sun's, so there would be plenty of heavier-mass material for planets to form from, he said. [...] The Doppler detection method, which has revealed the majority of the 228 known extrasolar planets, measures shifts in the light from a star to detect the tiny wobble induced by the gravitational tug of an orbiting planet.

Because Alpha Centauri B is so bright and nearby, detecting a small terrestrial planet's miniscule wobble would be that much easier. Also, its position high in the sky of the Southern Hemisphere means it is observable for most of the year, just as the Big Dipper is observable for most of the year in the Northern Hemisphere."

This daring flyby requires exquisite technical finesse, but it has the potential to revolutionize our knowledge of the geysers of Enceladus. The Cassini mission team is eager to see the scientific results, and so am I," said Alan Stern, associate administrator of NASA's Science Mission Directorate, Washington in a statement

Apparently Scientists and mission personnel have determined that flying at close distances to Enceladus poses little threat to Cassini because, despite the high speed of Cassini, the plume particles are small. Add that to the fact that Cassini regularly crosses regions made up of dust-size particles in its orbit around Saturn.

Neat stuff. Good luck Cassini and PLEASE don't get burned.

What is to say that if one of these things changed that there would be no life on earth? Of course, there would be differences between the life that we know and the life that would have existed, that is a given in these new set of circumstances. The earth as we know is a perfect place for life and that life can be found almost anywhere on the planet. If we take the statement the earth is designed for life, let's put that into a deductive model so we can see what we have:

The Earth was designed for Life.
Only Earth (or Earth like planets) has the ability to support life.
Life can only exist on the Earth or Earth like planets.

All we need is to find life that does not exist on earth, to show that environments unlike Earth's can support living things and from that we can take the earth was not designed for life, since other places that are not like the earth has life on them. As soon as life not from earth exists then we either have to reject the idea of a designed earth or we have to consider that other planets or places in the universe are also designed. It just happens that the ‘unique' set of circumstances makes the earth a successful place for life , being successful is different from the notion of a designed earth. Carolyn Porco discusses the idea that one of Saturn's moons Enceladus has the three building blocks of creation; liquid water, organic materials and heat. This was discovered via the last probe that went passed the moon and in theory it is possible that life on Enceladus is completely achievable. This moon has the right environment for the life as we know it to exist. If it is later discovered that there is life on Enceladus, which would most likely be in the form of micro organisms, then that would prove false the statement the Earth is designed for life and we would have to rethink the statement to produce something like the earth and other places are designed for life. Or it would be equally likely that the statement some places in the universe have a greater likelihood of life depending on certain factors, would be an acceptable replacement. This is not design but rather chance and a certain possibility considering the size of the galaxy.

It is interesting that if life on Enceladus is found, where would this leave the idea of evolution as a scientific theory? I think that it would support the idea strongly, once we have removed the idea of the Earth being designed for life we are left with the notion that life is designed for the earth, even if we assume that the Earth is such a great place for life, then nothing better than evolution explains both this life in two places in our solar system.

I cannot wait until the next mission to Enceladus!

As Cassini bravely dived through the plume at 15 km/s, the spacecraft's Ion and Neutral Mass Spectrometer tasted organic materials, volatile gases, water vapour, carbon dioxide and carbon monoxide, some 20 times denser than expected. 

"A completely unexpected surprise is that the chemistry of Enceladus, what's coming out from inside, resembles that of a comet," said Hunter Waite, principal investigator for the Cassini Ion and Neutral Mass Spectrometer.  "To have primordial material coming out from inside a Saturn moon raises many questions on the formation of the Saturn system."

Heat radiating from the entire length of 150 km-long fractures (the tiger stripes) is seen in this best-yet heat map of the active south polar region of Saturn's ice moon Enceladus.  The measurements were obtained by the Cassini spacecraft's Composite Infrared Spectrometer from the spacecraft's close flyby of the moon on March 12, 2008.  Credit:NASA/JPL/GSFC/SwRI/SSI

Another discovery by Cassini shows that the so-called tiger stripes, the source of the geysers, are 17 deg C warmer than previously seen and 93 deg C warmer than other regions of the moon.  These surprisingly high temperatures make it more likely that there’s liquid water not far below the surface.  Enceladus, now joining Jupiter’s moon Europa, to have a subsurface ocean.  Another possible place to look for life.

Organic material + warmer temperature + possible liquid water = good place to look for life.

Some essential building blocks needed for life do exist at Enceladus.  Although there is no evidence of life there now, but it just don’t stop us from wondering, right?

This is an artist's concept of Saturn's rings and major icy moons.  Enceladus is located in the densest region of Saturn's E-ring, possibly indicating there is some relationship between the geyser emissions and ring density.  Credit: NASA/JPL

Cassini will return in August for an even more daring, lower flyby of this strange, gassy moon.

Source: NASA Mission News

The beau is changing channels on the TV. "I heard it, I heard, it's music, just a snatch of it..." I hear on BBC's Torchwood (9:10 pm) as though an answer to my thoughts. The channel switches again back to IFC. I caught it though, just enough.

I looked up "elite moons", chose the url of interest and that is that. Tonight's anagram comes from two bubbles in the collage, "Somebody is looking at me! [and] Of course, lots of people look at us!" The anagram reads, "I also spoke to Lamb of God of secrets you look up elite moons." I decided not to punctuate it specifically. Notice in the collage the question, "Does art imitate 'life' or does 'life' imitate art?" The anagram could also read "you look up, see moon lit" instead of you look up elite moons. You and I are often interchangeable in my anagrams. It's a mirror image thing.

Not so fast, padre. Of couple of recent announcements have shed more light on the almost certain notion that life exists elsewhere in this big, old Cosmos. And where there's life, there must be the potential for intelligence (except, of course, within the Bush White House.)

Last week, scientists using the Hubble Space Telescope announced they've detected organic molecules on a huge planet some 63 light-years away. The planet, poetically dubbed HD 189733b, orbits a star in the constellation Vulpecula.

The discovery proves that researchers have the capability to find the basic building blocks of life outside our Solar System. They'll now use HST to examine smaller, more optimally positioned planets that have greater potential for supporting life.

HD 189733b has traces of water, a discovery announced in 2007, and methane. Scientists seek four substances - water, methane, carbon dioxide, and oxygen - when looking for signs of life on a planet.

Mark Swain, head of NASA's Jet Propulsion Laboratory team responsible for the discovery, calls it "a dress rehearsal for future searches for life on more hospitable planets." HD 189733b is too close to its host star - and therefore too hot - to support life as we know it.

Closer to home, the Cassini spacecraft, which has been studying Saturn's neighborhood, has "tasted" an organic soup emanating from the gas giant's moon, Enceladus. (By the way, don't you love the term "gas giant"? It signifies the massive outer planets of our Solar System: Jupiter, Saturn, Uranus, and Neptune. It can also refer to me after I've gorged on a pizza with everything.)

Anyway, Enceladus's "soup" contains water vapor and key organic chemicals. According to Dennis Matson, Cassini project scientist at the JPL in Pasadena, "Enceladus has got warmth, water, and organic chemicals, some of the essential building blocks needed for life."

Give us a few more decades and I'm certain scientists will find living, breathing creatures roaming some distant planet. Just as the spectacular photograph of the earthrise taken by the Apollo 8 astronauts changed the way we view our world (well, some of us,) the realization that beasts and intellectuals may populate other planets ought to put us even more in our places.

Who, then, will be the apple of god's eye?

Next time,

Big Mike

Os cientistas acreditam que os “geysers” que expelem água a até 400 metros por segundo podem comprovar a existência de água no estado líquido sob a superfície congelada de Enceladus.

Os dados coletados devem fornecer detalhes minuciosos das fraturas que marcam a superfície de Enceladus, permitindo uma avaliação geológica da história da lua e a comparação dos pólos norte e sul.

As novas imagens mostram que, comparado ao pólo sul, o pólo norte de Enceladus é geologicamente bem mais antigo, mantendo diversas crateras de diferentes tamanhos. Tais crateras aparecem em vários estágios de erosão e alteração por atividade tectônica e, provavelmente, pelo aquecimento interno. Muitas delas parecem divididas por fendas que, aparentemente, encontram-se em todas as partes do terreno ocupado pelas crateras.

Durante o vôo próximo à lua, o analisador de poeira cósmica (CDA) apresentou uma breve falha de sistema, de modo que os dados referentes a ele não foram gravados. O CDA é responsável pela análise de composição das pequenas partículas que atingem o instrumento. Tais informações seriam extremamente importantes para conhecer a origem dos jatos de vapor exalados do pólo sul de Enceladus, supostamente responsáveis por um dos anéis de saturno.
A informação oficial está em http://www.nasa.gov/mission_pages/cassini/media/cassini-20080313.html (em inglês).

Apesar da inesperada falha, as informações obtidas no dia 12, juntamente com o que se espera conseguir na nova visita da Cassini em 9 de outubro devem mostrar dados do que é expelido para analisarmos a densidade, tamanho, composição e velocidade das partículas. Entre outras coisas, os dados recentemente coletados devem ajudar a compreender se os gases expelidos são iguais aos que formam o halo de partículas ao redor de Enceladus. Desta forma podemos determinar como os jatos se formaram.

Os jatos foram descobertos em 2005, quando constatou-se que o halo de gelo e gás ao redor de Enceladus mantinha o anel E de Saturno.

Esta foi a primeira das quatro viagens da Cassini a Enceladus a serem realizadas em 2008. Durante esta visita, a sonda ficou a até 50 quilômetros de distância da superfície da lua de Saturno no momento de maior proximidade, sendo que passou pelos jatos oriundos do pólo sul a 200 quilômetros de altura. As próximas aproximações podem obter distâncias ainda menores, até que a missão em Saturno acabe em Junho. Após esta investida de quatro anos, a Nasa cogita a possibilidade de uma nova missão à região de Saturno com mais sete visitas a Enceladus.

These images show Saturn's moon Enceladus, as captured by the Cassini spacecraft. It recently flew through the plumes from Enceladus's icy geysers, and took some photos either side of the flyby.

The surface of Enceladus may look like rock, but it is actually ice.  Amazingly, there may even be a liquid water ocean underneath. Unforunately we'll have to wait a while yet for the results of the geyser flyby to come back, but in the meantime...

Click here for more information on the flyby and on Enceladus's mysterious geysers.

Enceladus is the 6th largest moon of Saturn (~500 km in diameter).

On March 12, 2008, this man-made moon met the natural moon... at closest approach of 50 km! That was very close!

This 3-image mosaic is the highest resolution view yet obtained of Enceladus’ north polar region during Cassini’s March 2008 flyby of Enceladus.  Credit: NASA/JPL/Space Science Institute.  More photos of March 2008 flyby of Enceladus.

Once upon a time, in year 2005, Cassini performed several close flybys of Enceladus and discovered evidence for geyser-like jets.  These continuous eruptions of ice water create a gigantic halo of ice dust and gas around Enceladus, which are the source of the material in Saturn’s tenuous E-ring.

This false-colour view taken on Nov. 27, 2005 identify the source locations for individual jets spurting ice particles, water vapour and trace organic compounds from the surface of Saturn's moon Enceladus. Credit: NASA/JPL/Space Science Institute.

On March 12, 2008, this was what happened: Cassini, flying at about 15 km/s, dived through the icy water geyser-like jets, snatching up precious samples that might point to a water ocean or organics inside the little moon.  The geysers emanate from fractures – casually referred to as “tiger stripes” – running along the moon’s south pole, spewing out water vapour at ~400 m/s.

The close encounter by Cassini provides a much more detailed look at the “tiger stripes” that modify the surface.  New images show that compared to much of the south polar region on Enceladus, the north polar region is much older and pitted with craters of various sizes.

This close-up view of Enceladus taken on July 14, 2005 shows a distinctive pattern of continuous, ridged, slightly curved and roughly parallel faults within the moon's southern polar latitudes. These surface features have been informally referred to by imaging scientists as "tiger stripes".  Credit: NASA/JPL/Space Science Institute.

This was the first of 4 Cassini flybys on Enceladus this year.  During this flyby, the spacecraft came within 50 km of the surface at closest approach and 200 km while flying through the plume.  Future trips may bring Cassini even closer.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency.

Source: CICLOPS Press Release

Another interesting article from The Planetary Society Weblog

In other wet news, the Cassini-Huygens probe successfully buzzed Saturns moon Enceladus yesterday at a height of 50 kilometers (30 miles) and a speed of 14.4 kilometers per second (32,000 miles per hour). Good work, yall. The data is back on earth, and is being analysed today. The reason they're doing this is that Enceladus seems to have jets of ice spewing out of it!?!?!??. Here's what they write about it:

"There are two types of particles coming from Enceladus, one pure water-ice, the other water-ice mixed with other stuff," said Sascha Kempf, deputy principal investigator for Cassini's Cosmic Dust Analyzer at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. "We think the clean water-ice particles are being bounced off the surface and the dirty water-ice particles are coming from inside the moon. This flyby will show us whether this concept is right or wrong."
In 2005, Cassini's multiple instruments discovered that this icy outpost is gushing water vapor geysers out to a distance of three times the radius of Enceladus. The moon is only 500 kilometers (310 miles) in diameter, but despite its petite size, it’s one of the most scientifically compelling bodies in our solar system. The icy water particles are roughly one ten-thousandth of an inch, or about the width of a human hair. The particles and gas escape the surface at jet speed at approximately 400 meters per second (800 miles per hour). The eruptions appear to be continuous, refreshing the surface and generating an enormous halo of fine ice dust around Enceladus, which supplies material to one of Saturn's rings, the E-ring.

That's so great. If Enceladus has a subterranean ocean, it might have some kind of fish, which is important because they could be really delicious.

 Cassini to make audacious flyby

Now, Cassini is flying back to discover more about Enceladus, but it's doing something a bit different to what space probes usually do. It will fly directly into the fountains of material above the geysers, sometimes at a height of just 30 miles above the surface. Rather than just taking photos, it will collect samples of the material that the geysers are releasing, and analyze it to see what its chemical composition is like. Click here for NASA's Enceladus Flyby blog.

But it's not just huge geysers that make Enceladus interesting. Think how Yellowstone's Old Faithful works - it's all down to the heat of the Earth warming up the water so that it shoots upward. It's not much different on Enceladus - in fact, Enceladus is a very geologically active body, and is among only two other Solar System bodies that have been seen erupting (the other two are Jupiter's moon Io and Neptune's satellite Triton).

Unlike on Earth where magma is the hot material, it is thought to be water-based on Enceladus. What causes the heat in a body so far away from the Sun? The main theory is that Saturn's gravitational pull causes 'tidal friction', which generates heat in this otherwise icy moon.

Wait a minute... water, heat - they're two key ingredients for life. It is indeed one of the places NASA is concentrating on in the search for ET. Enceladus is fast turning into one of the most exciting, revolutionary places in our Solar System - I can't wait for the discoveries to come in the weeks and months ahead.

Check out this great post by Kate Tobin on CNN's Sci-Tech blog. | This new interactive from NASA is a great resource for Enceladus - the intro video at the good is excellent. | Also, NASA has just released a site that lets you fly along with Cassini as it explores Saturn and its moons. It's pretty cool in my opinion.

UPDATE: NASA has now released some of the images from this flyby. Click here to see them.