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Watch this fantastic piece from Quanta Magazine on the quest for life in the universe led by David Kaplan. 

Who is this guy? He’s a theoretical particle physicist at Johns Hopkins University. If he looks familiar, it’s because he was the producer of - and featured in - the absolutely brilliant documentary film ‘Particle Fever’ concerning the Large Hadron Collider (LHC) at CERN and the fascinating human endeavor to understand well…everything. 

I had the fortunate pleasure of spending some quality time with David at the 2014 USA Science and Engineering Festival in DC. Fantastic mind, proven producer, and communicates the current state of exoplanet/astrobiology research quite well in this video. 

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Where Could Life Exist?

When NASA scientists announced earlier this year that they had found evidence of liquid water on Mars, imaginations ran wild with the possibility that life could exist somewhere other than here on Earth.

Scientists continue to explore the possibility that Mars once looked a lot like Earth — salty oceans, fresh water lakes, and a water cycle to go with it. That’s exciting stuff.

So where else are they looking? What exactly are they looking for?

There are nine places in our universe where scientists say life is a possibility. The locations range from a smoking hot planet like Venus to a moon that orbits Saturn called Enceladus, which looks a lot like a massive, tightly-packed ball of ice.

All of these places show signs that water is, or at least was, a possibility. They also appear to feature some kind of energy that could produce heat.

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Found! 3 Super-Earth Planets That Could Support Alien Life

The habitable zone of a nearby star is filled to the brim with planets that could support alien life, scientists announced today (June 25).

An international team of scientists found a record-breaking three potentially habitable planets around the star Gliese 667C, a star 22 light-years from Earth that is orbited by at least six planets, and possibly as many as seven, researchers said. The three planet contenders for alien life are in the star’s “habitable zone” — the temperature region around the star where liquid water could exist. Gliese 667C is part of a three-star system, so the planets could see three suns in their daytime skies.

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Earth is expected to be habitable for another 1.75 billion years

Findings published today in the journal Astrobiology reveal the habitable lifetime of planet Earth. The research team looked to the stars for inspiration. Using recently discovered planets outside our solar system (exoplanets) as examples, they investigated the potential for these planets to host life.

“We used stellar evolution models to estimate the end of a planet’s habitable lifetime by determining when it will no longer be in the habitable zone. We estimate that Earth will cease to be habitable somewhere between 1.75 and 3.25 billion years from now. After this point, Earth will be in the ‘hot zone’ of the sun, with temperatures so high that the seas would evaporate. We would see a catastrophic and terminal extinction event for all life,” said Andrew Rushby, who led the research.

However, conditions for humans and other complex life will become impossible much sooner - and this is being accelerated by anthropogenic climate change.

(GIF from the video of a geostationary satellite Electro-L)

This is the best image we have of the dwarf planet Ceres.

It’s a mysterious place that we know little about. A year ago, however the Herschel Space Observatory discovered that it’s got a tenuous atmosphere of water vapor.

It’s now believed that there are cryovolcanoes blasting liquid water up out of the surface.

Could Ceres host an entire liquid ocean of water? What’s more - if there is liquid water, could there be life?

NASA’s Dawn mission will arrive soon. On January 20th they will release it’s first image of Ceres.

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Quantum Tunneling Allows “Impossible” Chemical Reactions to Occur in Space

New research has revealed that chemical reactions previously thought to be ‘impossible’ in space actually occur ‘with vigor,’ a discovery that could ultimately change our understanding of how alcohols are formed and destroyed in space – and which could also mean that places like Saturn’s moon Titan, once considered too cold for life to form, may have a shortcut for biochemical reactions.

A team at the University of Leeds, UK recreated the cold environment of space in the laboratory and observed a reaction of the alcohol methanol and an oxidizing chemical called the ‘hydroxyl radical’ at minus 210 degrees Celsius. They found that not only do these gases react to create methoxy radicals at such an incredibly cold temperature, but that the rate of reaction is 50 times faster than at room temperature.

They also found that this faster than expected reaction can only occur in the gas phase in space, that a product is formed (CH3O) – and that it can only form via a phenomenon they call ‘quantum tunneling.’…

The tunneling phenomenon is based on the quirky rules of quantum mechanics, which contend that particles do not tend to have defined states, positions and speeds, but instead exist in a haze of probability. This means that although a given particle might have a strong probability of being on one side of a barrier, there is still a very small chance of it actually being found on the other side of it – in effect allowing it to occasionally ‘tunnel’ through a wall that would otherwise be impenetrable…

Put simply, [they say] that the research shows that organic chemistry can occur in space, here converting an alcohol into an alkoxy radical – which can then go on to form a carbonyl group such as formaldehyde. 

“So we are showing that one functional group can be converted to another despite the cold conditions of space. Reactions that were discounted in space because it was too cold may now occur – owing to the tunneling,”…

 

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Where the Sun Don’t Shine: Alien Life in Sunless Places

Photosynthesis—the harvesting of sunlight to produce energy—is the ultimate driver of virtually all life on the surface of our planet.

Most photosynthetic creatures rely on optical light, the kind we see, to energize their biological machinery. Yet some can make use of lower-energy (and invisible to our eyes) infrared light. And in the case of one kind of bacteria—discovered years ago, deep underwater near a hydrothermal vent—this light need not even come from the Sun.

A new study explores the potential for photosynthetic life to persist in such sun-starved conditions. The research aims to shed light, as it were, on how organisms could live off of the dim infrared emissions from hydrothermal vents on alien worlds. Tantalizingly, such vents are theorized to exist beneath the surface of Jupiter’s ice-covered, oceanic moon Europa.

“When we became aware of bacteria using infrared light to photosynthesize, we felt very curious about checking the photosynthetic potential with this light because this is one measure of whether life could thrive around hydrothermal vents,” said Rolando Cardenas, a physicist at Central University “Marta Abreu” de Las Villas in Santa Clara, Cuba and a coauthor of the paper published in the May issue of Astrophysics and Space Science.

The new findings suggest that photosynthetic life as we know it would struggle to flourish given the small amount of available light in hydrothermal vent environments. But organisms that could make use of lower-energy infrared light might find themselves with plenty to get by on in sunless circumstances.

Life blooming in the deep dark
In the oceans, hydrothermal vents form near underwater volcanoes where tectonic plates are moving apart at mid-ocean ridges. Hot magma that burbles up into the seabed superheats passing water that then spews out of the ocean floor, laden with minerals. The minerals precipitate out of the plume, building up chimney-like structures known as black smokers.

Although these deep-sea hydrothermal vents do not sound like particularly hospitable places, the scalding billows are actually biological hot spots.

Various kinds of bacteria dine on the materials such as iron, hydrogen sulfide and ammonia belched out by the vents. These bacteria in turn support whole ecosystems around black smokers, most famously characterized by tube worms, but also home to strange snails, crabs and much more.

Eight years ago, researchers led by J. Thomas Beatty of the University of British Columbia discovered a hydrothermal vent bacterium whose livelihood requires more than just ensnaring vent-water chemicals. The bacterium, identified as belonging to the green sulfur family, needs light in order to obtain energy through a chemical reaction with sulfur. This green sulfur bacteria species, however, was found in waters some 2,400 meters (7,875 feet) deep in the Pacific Ocean, off of the coast of Mexico. Photons of sunlight cannot beam down much past about 200 meters (660 feet) in the water column before being completely absorbed. Therefore, the bacterium must use the measly portion of geothermal light generated by hydrothermal vents to survive. This geothermal light is emitted when the erupting superheated waters rapidly cool in the surrounding, barely-above-freezing sea floor aquatic environment.

The bacterial species possesses an antenna-like structure that enables it to efficiently capture light. “It’s the only example of an organism found that is thought to live off geothermal light,” said Robert Blankenship, a professor of biology and chemistry at Washington University in St. Louis who was involved in the 2005 study. “The organism uses a giant antenna complex that allows it to live under extremely low-light conditions—it’s about the best candidate you could come up with for living off of a hydrothermal vent through the absorption of photons.”

Follow the light
Studying the hardy, sun-deprived life in remote areas such as hydrothermal vents is unfortunately a tricky and costly endeavor—the bacterium in question has not been re-isolated since. The new study by Cardenas and colleagues therefore turns to a mathematical model to assess the photosynthetic potential around the vents.

The researchers started with a concept vent that emits a similar amount of light as those described in the Beatty paper. A negligible amount of this light comes in the form of higher-energy, optical wavelengths; well over ninety-nine percent of the available light instead streams forth as lower-energy infrared light.

“The higher-energy photons do not contribute in a meaningful way to the overall energy-reaping budget for deep-sea photosynthetic organisms,” said paper coauthor Osmel Martin Gonzalez, also of Central University “Marta Abreu” de Las Villas.

The research team plugged in equations describing photosynthesis rates for surface water phytoplankton, tweaking them because ultraviolet light that can damage the plankton, and thus hinder photosynthesis, does not reach oceanic depths. A range of irradiance levels was modeled, as well as water temperatures spanning about 390 degrees Fahrenheit (200 degrees Celsius) to around 750 degrees Fahrenheit (400 degrees Celsius), consistent with black smoker outpourings.

Not an easy living
Overall, the calculated photosynthesis rates for infrared light-harvesting creatures were not very high, meaning that relatively little usable energy was extractable from the hydrothermal vent’s emissions.

The results in this way jibe with the Beatty and Blankenship finding in that the green sulfur bacterium did not seem to be a dominant member of its community or a particularly robust species. “The organisms that we found in the vents on Earth, I’m convinced they were hanging on by their fingernails and just squeaking out a living,” said Blankenship.

Indeed, for subterranean or submerged alien life to draw enough energy through infrared photosynthesis might require fundamentally different means, or at the very least a significant expansion of the wavelengths known to be usable.

Cardenas and colleagues pushed the envelope by considering hypothetical organisms that could absorb light with a wavelength as long as 1300 nanometers (billionths of a meter). That wavelength is considerably longer (and thus less energetic) than the light that Earthly species can accommodate. The infrared range is considered to start at 700 nanometers, and organisms have been documented reaping this invisible light out to about 1000 nanometers, Blankenship said.

Still, Cardenas said that in going a bit beyond terrestrial biology, he thinks that photosynthetic microbes could manage a living by the light from underwater hydrothermal vents. “Even with photosynthesis only until 1100 nanometers, green sulfur bacteria could do photosynthesis to some extent in a similar environment in Europa or other planetary bodies,” said Cardenas.

Blankenship is a bit more skeptical. He pointed out that the water around hydrothermal vents would probably absorb much of the infrared light available, leaving only a very narrow patch of real estate for photosynthetic creatures to occupy, and one that would put them perilously close to the superheated water itself. [6 Most Places for Alien Life in the Solar System (Countdown)]

“The amount of light that comes out of the vents at least here on Earth is very, very low,” said Blankenship. “Still, it’s always good to think about these things.”

Under the Europan ice
At this point, the characteristics of hydrothermal vents on Europa and their attendant heat and light output are pure speculation. “Detailed internal models of Europa are still under some controversy,” said Cardenas.

Europa has a thick, icy crust that scientists are pretty sure covers an ocean kept liquid by tidal flexing as Jupiter’s gravity squishes and squeezes the moon. This flexing could also spur tectonic-like processes in Europa’s mantle, leading to hydrothermal vents on its subsurface ocean’s floor.

“If that holds true,” said Cardenas, “then we can expect hydrothermal vents there and—why not?—forms of life relying on principles similar to those in Earth’s hydrothermal vents.”

For now, infrared photosynthesis as a sole or complementary means of energy production by extraterrestrial microbes around alien hydrothermal vents looks like a long shot; the use of minerals, as practiced with great success in our oceanic abysses, makes more sense. Then again, no one had expected to find an abundance of life teeming around black smokers when they were discovered in 1977.

“Life does seem to find a way,” said Cardenas. “We look forward to further studying infrared photosynthesis and its implications for life in less conventionally terrestrial habitats.”

This story was provided by Astrobiology Magazine, a web-based publication sponsored by the NASA astrobiology program.

via Space.com

Most Amazing Exoplanets

The term ‘exoplanet’ applies to any planet outside of our solar system. At last count, we have identified 3,538.

Out of the thousands of planets we know about, some of them are incredibly bizarre compared to what we are used to seeing in our own solar system. Here are some exoplanets with very unique characteristics:

Kepler-78b

The most astounding fact about Kepler-78b is that it shouldn’t even exist, according to our current knowledge of planetary formation. It is extremely close to its star at only 550,000 miles (900,000 kilometers). As a comparison, Mercury only gets within 28.5 million miles (45.9 million kilometers) of the sun in the nearest point of orbit. With that proximity, it isn’t clear how the planet could have formed as the star was much larger when the planet formed. With its current distance, that would mean it formed inside the star, which is impossible as far as we know. 

The planet itself is only slightly larger than Earth, though surface conditions are markedly different. The temperature on the surface is estimated to be 4300° F (2400° C), which is nearly nine times as hot as the temperature on Venus. Unfortunately for Kepler-78b, it is likely that the star’s gravitational pull will gradually bring the star closer and totally consume it in the next 3 billion years.

WASP-12b

While Kepler-78b still has about 3 billion more years before getting consumed by its star, the process is well underway for WASP-12b. This exoplanet is actively getting pulled apart by its parent star, much to the delight of astronomers who can watch the process unfold. So much material has been pulled away from the planet, it has been pulled into an oblong football shape. Astronomers have estimated that WASP-12b has about 10 million more years until it is completely pulled apart by the star.

The planet is described as a “hot Jupiter” as it is a gas planet that is about 40 percent larger than Jupiter. It is currently so close to its star that it only takes 1.1 Earth days for the planet to complete a full orbit. The star, WASP-12, is G-type main sequence star, just like our own sun. It is located about 800 lightyears away in the Auriga constellation.

TrES-2b

TrES-2b has been dubbed the “dark planet” because it does not reflect light. If we were able to view it directly, it would likely just look like a coal-black ball of gas. At 1800°F (1000°C) the planet is way too hot for clouds, which would help reflect the star’s light. The red tinges are areas of superheated gas. Other darker planets only reflect about 10% of the star’s light, but TrES-2b only reflects about 1%, making it the darkest planet ever discovered.

Why is TrES-2b so dark? Scientists aren’t quite sure. Right now, the best guess is that the majority of the planet’s composition is something like sodium or potassium which absorbs light. This dark world is located about 750 lightyears away in the Draco constellation. 

HD 189773b

HD 189773b is pretty exciting. It is relatively close, at only 63 lightyears away. It is also the first planet to have its color determined and it turned out to be a pretty blue planet, just like Earth. Unlike Earth, however, HD 189773b is a gas giant with a temperature that reaches a sweltering 1800°F (1000°C). The weather gets more extreme, because intense pressure and temperature turns silicate particles in the atmosphere into glass, which then rains down. As if that doesn’t sound dangerous enough, the winds have been estimated to gust at 4,000 mph (7,000 km/h) which really whips those glass particles around. 

55 Cancri e

55 Cancri e is twice the size of Earth but is nearly 8 times more massive and twice as dense. Last fall, researchers deduced that the mass of the planet was largely carbon. Due to the pressure and surface temperature of 4892°F (2700°C) it very well could have formed diamond. It is so close to its parent star it takes a mere 18 hours for the planet to complete a full orbit.

55 Cancri e is only about 40 light-years away from us in the Cancer constellation. The parent star is much more carbon than our own sun, so it might be too surprising that planet e is also carbon-rich. From there, it isn’t much of a stretch to assume that the other four known planets in the system would also have a high carbon content.

Because of these extreme conditions, astronomers don’t believe that 55 Cancri e has an atmosphere, making it a poor candidate for the possibility for life. However, it is close enough for astronomers to use it to test hypotheses about planetary formation.

PSR B1620-26b

Nicknamed “Methuselah,” PSR B1620-26b is the oldest known exoplanet. The planetary system formed approximately 12.7 billion years ago, when the Milky Way galaxy was in its infancy. It is located in the Scorpius constellation about 12,400 lightyears away. 

Methuselah orbits binary stars and goes around them in a circumbinary orbit. As if Methuselah’s age isn’t interesting enough, the fact that it orbits two mismatched dead stars is quite unusual. One of the stars is a pulsar and the other is a white dwarf. Since Methuselah is found in a dense star cluster, astronomers initially thought it could be a star as well, and would be considered a brown dwarf. Measurements from the Hubble would confirm that Methuselah is a planet, and it remains the oldest one we’ve ever discovered.

TrES-4

Located 1,400 lightyears away in the Hercules constellation, TrES-4 is the largest exoplanet we have discovered so far. Though it is over 1.7 times the size of Jupiter, it has an extremely low density and is categorized as a “puffy” planet. The planet’s density is about the same as cork, which came as quite a shock. Astronomers attribute this to extreme heat of 2,300° F (1,260° C) due to is proximity to the star. At only 4.5 million miles (7.2 million kilometers) away from its sun, TrES-4 is able to complete an orbit in three Earth days.

Gliese 436 b

30 lightyears away in the constellation Leo, Gliese 436 b is a planet that is about as massive as Neptune. The planet also happens to be covered in burning ice - though the ice isn’t anything like what we’re used to. The extreme pressure of the planet forces the water to stay in solid form, even though the temperature exceeds 570° F (300° C). The outer layer of the solid water is superheated and comes off as vapor. Water has over 10 solid states, not including common ice.

In its present position, the water would not have been able to condense down into a solid, indicating that it migrated toward its sun after it formed.

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Dark matter is necessary for the origin of life

“Without the additional gravitation of a massive dark matter halo surrounding a galaxy, the overwhelming amount of material ejected from a supernova would escape from galaxies and wind up floating freely in the intergalactic medium, never to become incorporated into future generations of star systems. In a Universe without dark matter, we’d still have stars and galaxies, but the only planets would be gas giant worlds, with no rocky ones, no liquid water, and insufficient ingredients for life as we know it.”

Dark matter is necessary to explain the motions of stars, galaxies and the formation of structure in the Universe, but most surprisingly is how its presence and abundance is essential to the existence of life in the Universe.

My latest for Forbes!

This newly processed image of Europa shows - in great detail - the cracks and fractures along the surface of Europa.

Europa’s surface is dynamic, constantly changing. It gets torn apart by tidal forces, and geysers of water fire up and over the fractures they came from - only to land and form a fresh layer of water ice.

This same pulling and pushing of Europa generates immense amounts of friction and therefore heat.

Below the icy surface - Europa has an ocean of liquid water:  possibly more water than there is on Earth.

In that ocean… we hope to find out. NASA proposed a mission called the “Europa Clipper” to orbit Jupiter in order to perform numerous flybys of the icy world.

The Clipper is hoped to be followed by an orbiter and a lander, all designed to explore the habitability of Europa’s ocean.

It may be the best candidate for extraterrestrial life in our solar system

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The is a tardigrade, aka water bear. And this little thing can survive the most extreme conditions — boiling heat, freezing temperatures, even the vacuum of space. But what’s so special about this little guy?

Well this microorganism can survive from just above absolute zero, to well above the heat of boiling water. Pressures greater than the deepest point of the ocean by 600%. They can live without food or water for 10 years.

The European Space Agency even sent some tardigrade up to space, under an experiment called TARDIS — tardigrades in space. (Wink face, Doctor Who) Where the results were stunning. Many of them survived the solar radiation, vacuum conditions, freezing temperature, dehydration and other extreme conditions. And.. It didn’t even affect their reproductive behaviors.

So what? It can live in extreme conditions, why does that matter?

Well the tardigrade have showed us that where life can exist, it will exist. Which makes us realize, maybe life doesn’t need to exist under all the conditions we once believed. If tardigrades can exist under these conditions, what about extraterrestrials?

Knowing about the tardigrade, there are so many more possibilities of finding extraterrestrial life. Now its up to time, and the work of our diligent scientists to show us where it exists — I know its hiding out there somewhere!

Three Badass Subfields of Astronomy: Astrobiology, Astrochemistry, and Astrophysics

I’ve been receiving a lot of messages from people curious to know the differences between these subfields of astronomy. So, I’ve written a post giving a simple definition and a brief description of what’s involved in each.

Astrobiology (also known as exobiology) is the study of the origin, evolution, and distribution of life here on Earth and—more importantly—the entire universe. Using existing origin theories and models, this relatively new branch of astronomy is primarily focused on analyzing and discovering the amazing possibility of extraterrestrial life.

Astrobiologists face some distinct problems in their work. Many planets are completely unsustainable to life as we know it. Scorching or freezing temperatures, seemingly gentle rain that would actually burn the skin off of your body, or hurricanes the size of Earth itself are quite common planetary conditions in the universe. Astrobiologists attempt to simulate the possibilities of life cropping up in these unlikely conditions. Whether or not a life form can survive in these types of environments will reveal just how diverse and adaptive it is. Despite nature seeming like an sadistic asshole, there is striking evidence for the resilience of life. Astrobiologists have outlined four requirements for life to survive:

  1. A liquid solvent in which molecules can move freely and interact. 
  2. An energy source.
  3. An atom which allows complex structures to exist.
  4. A sh*t load of time.

Considering that certain life forms here on earth have defied some of these requirements, it’s logical to presume that there is indeed extraterrestrial life. The fact that the conditions can literally be terrible and life can still survive, is enough to convince me there are almost certainly other forms of life in the universe.  

Additionally, if we do find evidence of other life forms in the universe, they will probably look almost nothing like little green men with large heads and telepathic abilities (although, that would be awesome). In fact, astrobiologists hypothesize that extraterrestrial life will most likely be far more exotic and diverse than anything we can possibly imagine. Nature has certainly shown that it has one hell of an imagination.

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Europa Beckons…

Slightly smaller than Earth’s moon, Jupiter’s moon ‘Europa’ is the sixth closest to the gas giant and the smallest of the 67 Galilean satellites.

Europa has been an other-worldly wonder for planetary scientists, but more so for astrobiologists due to the intriguing cracks and fissures among the icy crust. These cracks or ‘lineae’, are indicative of geologic activity similar to plate tectonics, which we experience and study on Earth as the crust of our planet moves and slides beneath our feet via the lithosphere, driving what is known as ‘continental drift’ amongst geoscientists.

Crack/rift in the Antarctic ice shelf of the Pine Island glacier photographed by NASA/GSFC

This image, taken by the Galileo space probe, reveal rust-colored fissures or ‘lineae’, similar to Earth’s oceanic ridges, which force fresh material upward from below the subsurface, effectively replacing/repairing these surface blemishes.

Continental drift results in subduction (see subduction zones) involving the movement of tectonic plates; in Earth’s case, these are the oceanic and continental crusts. The catalysts for this geologic activity are our distance from the sun and (Earth’s) moon. A similar relationship exists between Jupiter and Europa.

Why is this important?

Being as far (or close) to Jupiter as it is along with an accompanying eccentric (oval) orbit, vulnerable Europa is thought to experience “tidal flexing“ whereby the ocean beneath its surface is pulled and pushed by the tremendous gravitational force exerted by Jupiter. This process indeed flexes the icy crust of Europa to hyperextension of its subsurface, which is composed of a 62 mile-deep outer layer of water above a silicate mantle bolstered by an assumed iron/metallic core.

Subduction, subsurface tidal flexing, shifting of organic material…just think "lava lamp”
What does this mean?

It means further exploration for closer examination is needed to determine anything. However, at this point, here’s what we’ve come to understand:

These artist’s drawings depict two proposed models of the subsurface structure of the Jovian moon, Europa. Geologic features on the surface, imaged by the Solid State Imaging (SSI) system on NASA’s Galileo spacecraft might be explained either by the existence of a warm, convecting ice layer, located several kilometers below a cold, brittle surface ice crust (top model), or by a layer of liquid water with a possible depth of more than 100 kilometers(bottom model).

Random Sagan Fact: Carl Sagan was the first to propose the possibility of a subsurface ocean underneath Europa’s icy crust.
If a 100 kilometer (60 mile) deep ocean existed below a 15 kilometer (10 mile) thick Europan ice crust, it would be 10 times deeper than any ocean on Earth and would contain twice as much water as Earth’s oceans and rivers combined. Unlike the Earth, magnesium sulfate might be a major salt component of Europa’s water or ice, while the Earth’s oceans are salty due to sodium chloride (common salt). While data from various instruments on the Galileo spacecraft indicate that an Europan ocean might exist, no conclusive proof has yet been found. To date Earth is the only known place in the solar system where large masses of liquid water are located close to a solid surface. Other sources are especially interesting since water is a key ingredient for the development of life as we know it. [source]

But wait! There’s more…

As we continue to scrupulously pore over the data via the Galileo spacecraft’s 7.75 year mission in the Jovian neighborhood, we are discovering more about this planetary body than we (especially Galileo himself) could’ve ever predicted.

Recently observed (in images the spacecraft took in 1998) are “clay-like” minerals called phyllosilicates. The origin of these minerals are being best explained by a collision with an asteroid (likely 3,600ft in diameter) or comet (5,600ft. in diameter). Results of this study can be found here.

If this explanation sounds a bit far-fetched, think again. Asteroid/comet impacts are frequent among the solar system, as the July 1994 event of Comet Shoemaker-Levy 9 reminded us. Astronomers witnessed the comet breaking apart, colliding with Jupiter and producing a 24,000 K (as in Kelvin) fireworks display rivaling 6,000,000 megatons of TNT or 600x the world’s nuclear arsenal. Shoemaker-Levy 9 alerted us to the cosmic shooting gallery we find ourselves in, along with our under preparedness for sporadic rendezvous with these double-edged, life-dispersing/revoking crumbs from our solar system’s early formation.

Orbits of 1,000 categorized potentially hazardous asteroids (PHA’s) [source]

Thus, the importance of space exploration and specifically, the recent measure introduced by the UN to formulate an asteroid defense plan.

Recommended: BBC Animated Guide To Shoemaker-Levy 9’s Impact With Jupiter; Impact Jupiter: The Crash of Shoemaker-Levy 9 by David H. Levy, co-discoverer of the comet

Although Shoemaker-Levy 9 may seem at first glance to be an isolated incident (broken up into its 21 constituent icy chunks, mind you…) it’s far from the first or last time Jupiter has been blindsided by a collision of such magnitude.

In 2009, a comet/asteroid/meteor the size of the Pacific Ocean struck Jupiter. Dubbed the ‘Wesley impact’ (due to the amateur astronomer who discovered it), the object was estimated to be about 200-500 meters in diameter. To put this in perspective: if this object would have collided with Earth, the devastation would be cataclysmic and crippling human civilization. [source]

If the allure of organic material-providing collisions isn’t enough of a driver toward an imperative mission to Europa, the most recent discovery of water vapor being ejected 200 kilometers (125 miles) above the surface via potential plumes should be a call to (scientific) arms.

“If those plumes are connected with the subsurface water ocean we are confident exists under Europa’s crust, then this means that future investigations can directly investigate the chemical makeup of Europa’s potentially habitable environment without drilling through layers of ice. And that is tremendously exciting,”
- Lorenz Roth of Southwest Research Institute in San Antonio and lead author of the Hubble Space Telescope discovery said in a NASA press release

The plumes were detected via “old faithful” herself, NASA’s Hubble Space Telescope. While viewing a “hot spot” in ultraviolet light on Europa’s south pole, the colors (wavelengths) of light revealed copious amounts of hydrogen and oxygen.

“The idea is that water erupting from Europa is exposed to space (Europa has no atmosphere). Jupiter has a ridiculously intense magnetic field, and electrons caught in that field are accelerated to high speed. These electrons slam into the water molecules from Europa, breaking them up into individual atoms of hydrogen and oxygen, which then reveal their presence by glowing in the ultraviolet.

Interestingly, earlier observations showed no trace of this light, and that actually supports the idea that this light is from a geyser. Why? Those older observations were taken when Europa was close to Jupiter, but the new observations were taken when Europa was farther away. This is critical: When the moon is close to Jupiter, the squeezing from the planet’s gravity is maximized, and when it’s farther away the squeezing is lowered. This means that any deep cracks in the surface are squeezed closed when Europa is near Jupiter and relaxed, opened up, when it’s farther away. If water from the subsurface ocean were to escape through cracks, it would be when they’re open. So these observations precisely fit the idea that this is what we’re seeing.”
- Phil Plait, Slate magazine


This artist concept illustrates two possible cut-away views through Europa’s ice shell. In both, heat escapes, possibly volcanically, from Europa’s rocky mantle and is carried upward by buoyant oceanic currents. [source]

How much water are we talking?

It’s being estimated that 7 tons of water are erupting every second at over 1,500 miles per hour. "Three times faster than a passenger jet,” exclaims astronomer/science blogger Phil Plait. He continues in his recent article ‘Europa Erupts! Possible Geyser of Water Seen on Jupiter’s Moon’

“As it happens, we know of another moon with geysers: Saturn’s moon Enceladus. Europa is much larger than Enceladus (3,100 km versus 500 km) and so has much stronger gravity. That means that for a given speed for the water, the plume won’t stretch as high on Europa as it would on Enceladus.

Still, it’s worth comparing. On Enceladus, the plumes are higher, reaching 500 km (about 310 miles) off the surface, move more slowly at 300–500 meters per second (700–1,100 mph), and only out pump about 200 kilograms (about 450 pounds) of water per second. Because of Enceladus’ lower gravity, some of that material escapes from the moon into space. For Europa, with its stronger gravity, the material falls back to the surface where it freezes.

Dramatic plumes, both large and small, spray water ice out from many locations along the famed “tiger stripes” near the south pole of Saturn’s moon Enceladus. [source]

The geysers on Enceladus are also at the moon’s south pole—stress from Saturn’s gravity is strongest there, just as stress from Jupiter is strongest at Europa’s poles—and dozens have been found along long cracks colloquially called tiger stripes. The Cassini spacecraft has been orbiting Saturn for nearly a decade, and we have fantastic high-resolution images of Enceladus, allowing us to identify the regions in the cracks where the geysers originate.”

Do underground oceans vent through the tiger stripes on Saturn’s moon Enceladus? Long features dubbed tiger stripes are known to be spewing ice from the moon’s icy interior into space, creating a cloud of fine ice particles over the moon’s South Pole and creating Saturn’s mysterious E-ring. Evidence for this has come from the robot Cassini spacecraft now orbiting Saturn. Pictured above, a high resolution image of Enceladus is shown from a close flyby. [source]

To further demonstrate the importance of these plumes and what this means for planetary science/astrobiology, I invite you on a trip to Saturn, courtesy of Cassini Imaging Team lead and planetary scientist Carolyn Porco, as she delivers a Carl Sagan-esque TED talk on the visual wonders recovered by the Cassini spacecraft, along with one of the most intriguing moons in the solar system, Enceladus.

There will be so much more to come as this develops. For now, keep looking up and stay curious! The moons of Jupiter are a beautiful sight to view through a telescope; even more so now, as we continue to learn more about our neighboring planets and their accompanying satellites…

‘Alien megastructure’ could explain mysterious new Kepler results

Strange signals from a distant star are defying natural explanation. There is a remote chance that they could be from an ‘alien megastructure’

By Stuart Clark

There’s a new mystery in the universe and it goes by the name KIC 8462852. It is a star approximately 1500 light years away from the Earth, and displays a strange pattern of dimming that has astronomers scratching their heads.

With many natural causes apparently ruled out, there is even the suggestion that the signals could be caused by a giant structure, built in space near the star, presumably by extraterrestrials.

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Life ‘not as we know it’ possible on Saturn’s moon Titan

A new type of methane-based, oxygen-free life form that can metabolize and reproduce similar to life on Earth has been modeled by a team of Cornell University researchers.    

Taking a simultaneously imaginative and rigidly scientific view, chemical engineers and astronomers offer a template for life that could thrive in a harsh, cold world - specifically Titan, the giant moon of Saturn. A planetary body awash with seas not of water, but of liquid methane, Titan could harbor methane-based, oxygen-free cells.

The azotosome is made from nitrogen, carbon and hydrogen molecules known to exist in the cryogenic seas of Titan, but shows the same stability and flexibility that Earth’s analogous liposome does. This came as a surprise to chemists like Clancy and Stevenson, who had never thought about the mechanics of cell stability before; they usually study semiconductors, not cells.

The engineers employed a molecular dynamics method that screened for candidate compounds from methane for self-assembly into membrane-like structures. The most promising compound they found is an acrylonitrile azotosome, which showed good stability, a strong barrier to decomposition, and a flexibility similar to that of phospholipid membranes on Earth. Acrylonitrile - a colorless, poisonous, liquid organic compound used in the manufacture of acrylic fibers, resins and thermoplastics - is present in Titan’s atmosphere.

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One of the most interesting places in the solar system is Triton, moon of Neptune.

It orbits backwards which means it wasn’t formed with Neptune: it was captured.

There have been cases of rogue planets drifting alone through interstellar space - could Triton be one such planet, forced into submission by the gas giant?

Of further interest is the discovery that there may be several sources of internal heat for the moon: radioactive isotopic decay and tidal flexing.

The high amounts of ammonia (which would significantly lower the temperature in which water would exist in liquid form) and the internal heat could mean there’s a subsurface ocean of water…

It could be a unique opportunity to explore a planet from another solar system with our robots or another likely candidate for extraterrestrial life… the only thing we know for sure is that there’s a lot we don’t know.

The only time we’ve visited was when Voyager 2 flew by briefly in 1989.

NASA currently has no further plans to visit Triton…

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Serpentinization of Ocean Crust: Life’s Mother Engine? | NASA Astrobiology

In a new study published in Philosophical Transactions of the Royal Society B, NAI-funded scientists advance a theory about life’s origins based on the idea of “reservoir-mediated energy.” This paradigm—in cells—involves constantly filling up and depleting a kind of chemical reservoir that is created by pushing a lot more protons onto one side of a membrane than the other—just like pumping water uphill to fill a lake behind a dam.

Then, mimicking how hydroelectric turbines are driven by water flowing downhill, these protons are only allowed to flow back “downhill” through the membrane by passing through a turbine-like molecular “generator” which creates, instead of high-voltage electricity, a chemical fuel called ATP, the cell’s “gasoline.” All cells then “burn” ATP in order to power their vital processes. 

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On a side note: guys, this is literally what I want to do with my research; biogeochemistrySPACE, I mean, just look /AGRICULTURAL DOMESTICATION/ ON A MOLECULAR LEVEL, LIKE WHAAAAT. The way I see it is that while our metabolism suggests the potentiality of destruction (because we age, because of free radicals, because of oxygen, all that jazz)–these biological conundrums are really the result of chance and laws of physics. Because it worked against the physical entropy of the planet when life was originating. It was what got us started; it all boils down to the way the molecules moved, and the way it worked creating more ordered stuff, while everything else becomes disordered, the efficient survived and it’s literally evolution on the chemical level. Science though SCIENCE

Why scientists need to search for alien life on purple planets

Billions of years ago, when microbial life first emerged on Earth, our planet would have appeared purple from space. Armed with this knowledge, scientists now say we should be on the lookout for exoplanets tinged in a similar purple hue — a possible sign of extraterrestrial life.

Back during the Archean era, some three billion years ago, one of the more widespread forms of life were purple bacteria — photosynthetic microorganisms that inhabited both aquatic and terrestrial environments. These conditions would have been similar to the one recently discovered by Australian scientists, an ecosystem dating back 3.5 billion years.

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