Category: Space & Physics

Space Submarines Could Swim in Extraterrestrial Seas

By Chris Arridge, Lancaster University | August 3, 2016 11:56 am
space-submarine

Artist’s impression of a cryobot and submarine in the ice on Jupiter’s. (Credit: Europa. NASA/JPL)

One of the most profound and exciting breakthroughs in planetary science in the last two decades has been the discovery of liquid methane lakes on the surface of Saturn’s largest moon Titan, and liquid oceans under the icy surfaces of many of the giant gas planets’ other moons. Thrillingly, these some of these “waters” may actually harbor life.

Unfortunately, we don’t know much about them. Probes such as Juno and Cassini can only get so close. Also, subsurface oceans can only be sensed indirectly. The European Space Agency’s Huygens probe did land on Titan in 2005, but on a solid surface rather than on liquid. So how can we explore these seas? Read More

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Confessions of a Martian Rock

By Nina Lanza, Los Alamos National Laboratory | July 25, 2016 11:26 am
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The Curiosity rover (Credit: NASA)

I look at rocks on Mars for a living—a lot of rocks. Because of this, I’ve gotten pretty good at knowing what to expect and what not to expect when analyzing the chemical make-up of a Martian rock. You expect to find lots of basalt, the building block of all planets.

What I didn’t expect were large amounts of manganese. So when my colleagues and I found exactly that on a Martian rock called “Caribou” back in 2013, we thought, “This has to be a mistake.”

Caribou Conundrum

Trace amounts of the element manganese typically exist in basalt. To get a rock with as much manganese as Caribou has, the manganese needs to be concentrated somehow. The rock has to be dissolved in liquid water that also has oxygen dissolved in it.

If conditions are right, the manganese liberated from the rock can then precipitate as manganese oxide minerals. On Earth, dissolved oxygen in groundwater comes from our atmosphere. We’ve known for some time now that Mars once had vast oceans, lakes and streams. If we could peer onto Mars millions of years ago, we’d see a very wet world. Yet we didn’t think Mars ever had enough oxygen to concentrate manganese—and that’s why we thought the data from Caribou must have been an error.

The Hunt Is On

So what do you do when you find a Martian rock with a chemistry you didn’t expect? You go look for more.

When NASA’s Curiosity rover arrived at the Kimberly region of Gale crater, we went to work, looking at the mineral-filled cracks in sandstones on the floor of what was once a deep lake. We used the ChemCam instrument, which sits atop Curiosity and was developed here at Los Alamos National Laboratory, to “zap” rocks on Mars and analyze their chemical make-up. (In less than four years since landing on Mars, ChemCam has analyzed roughly 1,500 rock and soil samples.)

When ChemCam fires its laser pulse, it vaporizes an area the size of a very small pinhead. The system’s telescope on the rover peers at the flash of glowing plasma created by the vaporized material and records the colors of light contained within it. This light allows us here on Earth to determine the elemental composition of the vaporized material.

And what did ChemCam discover? More rocks filled with manganese oxides. So Caribou was not a mistake — far from it.

Why Does Manganese Matter?

We never expected to find manganese oxides on Martian rocks because we didn’t think Mars ever had the right environmental conditions to create them. We can look to Earth’s geological record for an explanation. More than 3 billion years ago, Earth had lots of water but no widespread deposits of manganese oxides until after photosynthesizing microbes raised the oxygen levels in our atmosphere.

Although there was already plenty of other microbial life on Earth at this time, these new photosynthetic microbes used sunlight energy in a new way and created a new type of waste product in the process: oxygen.

mars-rocks

The Curiosity rover examines the Kimberley formation in Gale crater, Mars. In front of the rover are two holes from the rover’s sample-collection drill and several dark-toned features that have been cleared of dust (see inset images). These flat features are erosion-resistant fracture fills that are composed of manganese oxides, which require abundant liquid water and strongly oxidizing conditions to form. The discovery of these materials suggests that the Martian atmosphere might once have contained higher abundances of free oxygen than in the present day. (Credit: MSSS/JPL/NASA)

By adding oxygen to the atmosphere, these tiny microbes transformed Earth’s environment. Suddenly, minerals never before formed on Earth started being deposited, including manganese oxides. This monumental environmental shift is recorded in the chemistry of rocks of that age all over the world. Earth has never been the same since. (Some hypothesize that more complex life forms, such as humans, might never have developed without this atmospheric change.)

So to summarize: In the Earth’s geological record, the appearance of high concentrations of manganese marks a major shift in our atmosphere’s composition, from relatively low oxygen abundances to the oxygen-rich atmosphere we see today. The presence of the same types of materials on Mars suggests that something similar happened there. If that’s the case, what formed that oxygen-rich environment?

How Did It Get There?

One way oxygen could have gotten into the Martian atmosphere is from the breakdown of water when Mars was losing its magnetic field.

Without a protective magnetic field to shield the surface from ionizing radiation, that radiation split water molecules into hydrogen and oxygen. Mars’ relatively low gravity couldn’t hold onto the very light hydrogen atoms, but the heavier oxygen atoms remained behind. Rocks absorbed much of this oxygen, leading to the rusty red dust that covers the surface today. While Mars’ famous red iron oxides require only a mildly oxidizing environment to form, manganese oxides require a strongly oxidizing environment. Finding manganese oxides suggests that past conditions were far more oxidizing than previously thought.

What’s Next?

NASA’s Opportunity rover, which has been exploring Mars since 2004, also recently discovered high-manganese deposits in its landing site thousands of miles from Curiosity, which supports the idea that the conditions needed to form these materials were present well beyond Gale crater.

(Credit: NASA/JPL-Caltech/Arizona State University)

The Gale Crater captured by the Thermal Emission Imaging System (THEMIS) on NASA’s Mars Odyssey orbiter. (Credit: NASA/JPL-Caltech/Arizona State University)

Of course, it’s hard to confirm whether the ionizing-radiation scenario I’ve presented here for creating Martian atmospheric oxygen actually occurred. But it’s important to note that this idea represents a departure in our understanding of how planetary atmospheres might become oxygenated. So far, abundant atmospheric oxygen has been treated as a so-called biosignature, or a sign of existing life.

The next step in this work is for scientists to better understand the relationship between manganese minerals and life. On Earth, they are highly related—but they certainly don’t need to be.

So how can we tell whether the manganese on Mars might actually be made by microbes? The answer is lots and lots of laboratory experiments. If it’s possible to distinguish between manganese oxides produced by life and those produced in a non-biological setting, we can apply that knowledge directly to Martian manganese observations to better understand their origin.

In the meantime, we’ll keep our eyes trained on the Martian surface and see what other secrets it has to reveal.

 

Nina Lanza is a staff scientist at Los Alamos National Laboratory, which has built and operated more than 500 spacecraft instruments for national defense. That background gives the Laboratory the expertise to develop discovery-driven instruments like ChemCam and its souped-up successor, SuperCam, also developed by the Laboratory and scheduled for the Mars 2020 rover mission.

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: Mars, space exploration

These Spacecraft Will Visit Jupiter After Juno

By Jordan Rice | July 4, 2016 7:00 am
Hubble captured stunning images of auroras in Jupiter's atmosphere. (Credit: NASA, ESA)

Hubble captured stunning images of auroras in Jupiter’s atmosphere. (Credit: NASA, ESA)

Juno (JUpiter Near-polar Orbiter) is the sixth spacecraft to study Jupiter (give or take a few gravity assists), but will be the second to fall into orbit around the gas giant following the Galileo probe in 1995.

It is part of NASA’s New Frontiers space exploration program that specializes in researching the celestial bodies of the solar system. Juno was launched on August 5th, 2011 from Cape Canaveral Air Force Station in Florida and intended to be placed in a polar orbit around Jupiter to study the planet’s composition, magnetic and gravity fields, and the polar magnetosphere. Even though Juno’s scientific mission only lasts for a year, many more spacecraft are headed Jupiter’s way. Read More

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How Researchers Will Carry Out the Search for Extraterrestrial Life

By Nathaniel Scharping | June 28, 2016 11:29 am
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The sun breaks over the surface of another planet in this illustration, potentially revealing the gases that make up its atmosphere. (Credit: sdecoret/Shutterstock)

Is there life beyond our planet? Astronomers have asked that question ever since we realized that there actually was something beyond our planet. Given the vastness of the universe, however, we’re not likely to journey out and meet it for ourselves anytime soon. Instead, astronomers are searching for a way to bridge the vast distances of interstellar space and search for subtle signs of life on other planets from right here on Earth.

SETI has garnered attention for its far-reaching aim: to make contact with intelligent extraterrestrial life. Other experiments, from the Golden Record tucked away in the Voyager missions, to the recently proposed Starshot program, hope that other civilizations will notice our wandering spacecraft.

If there is life, it will likely reveal itself through signs much more subtle than, say, a Dyson sphere. Instead, some astronomers are pinning their hopes on “biosignature” gases, molecules in a planet’s atmosphere that could only be produced by living organisms and observed from our corner of the universe. The telescopes of the near-future promise to give us the capability to peer into the atmospheres of distant planets and pick out their composition. But if life sends out gaseous greetings, what gases should we be “sniffing” for?  Read More

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Salts on Mars Are a Mixed Blessing

By David Warmflash | June 20, 2016 7:00 am
mars-lineae

Perchlorates are abundant on Mars, and they allow liquid water to flow. (Credit: NASA/JPL-Caltech/University of Arizona)

It’s a major component of solid rocket propellants. It allows water to exist as liquid on Mars, despite atmospheric pressure at the Martian surface being roughly 0.6 percent that on Earth. It also can be broken down to release oxygen that astronauts and future colonists in a Mars settlement could breathe.

It’s called perchlorate and it’s abundant on Mars –10,000 times more abundant in Martian dirt than in soils and sands of Earth. That may sound like a good thing, considering the useful properties of perchlorate, but there’s also a flip side.

Being a negative ion, perchlorate (ClO4) forms various salts, but it has detrimental health effects. Potassium perchlorate is used as a drug to treat certain forms of hyperthyroidism (overactive thyroid). But exposure to environmental perchlorate causes the opposite of hyperthyroidism, namely hypothyroidism — an underactive thyroid.

It would be devastating for Martian colonists.

An Ubiquitous Chemical Solves Two Mysteries

Perchlorate is all over the Martian surface. In 2009, NASA’s Phoenix lander identified perchlorate in the Martian dirt pretty much everywhere it looked. Then, last September, NASA’s Mars Reconnaissance Orbiter demonstrated very high concentrations of perchlorate salts within recurring slope lineae (RSL), features on the planet’s surface that were formed from relatively recent water flows. The finding solved a mystery of how Martian water could be liquid long enough to change the landscape.

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Recurring slope lineae are seen as dark streaks as salty water oozes from the walls of Garni Crater on Mars. (Credit: NASA/JPL-Caltech/University of Arizona)

Because of the thin atmosphere, pure water on the Red Planet can persist only as ice or vapor, depending on the temperature. But dissolved salts change the physical chemistry, enough that subsurface liquid water can emerge from time to time and stick around as lakes and streams.

Following the perchlorate could lead us to underground water, which in turn could lead to native microorganisms, a long-sought milestone in space biology. But it would also factor into the choice for landing sites for human missions and colonies, plus it would facilitate terraformation – changing the planet to be more like Earth.

A Source of Energy and Oxygen

The oxygen and energy contained in perchlorate make it a potential energy source on Mars, both for generating electricity and for rocket propulsion. Ammonium perchlorate was the main propellant in solid rocket boosters of the space shuttles that NASA flew from 1981-2011. Mars colonization, and even early human landings, will depend on utilization of Mars resources to fuel craft that will ferry people between the surface and orbit, where they will link with larger ships that make the interplanetary voyage.

Having four oxygen atoms per molecule also makes perchlorate useful to life-support systems. Colonists could employ certain microorganisms from Earth that break up the molecule to release O2. The extracted O2 could be pumped through life support systems of enclosed underground habitats.

Later, the process could be scaled up to enrich air that’s pumped into sealed caverns and craters to help achieve paraterraforming — creating Earth-like environments within limited enclosed areas rather than encompassing the entire planet.

Not a Solution for Liquid Water

Although high concentrations of perchlorate will maintain water in a liquid state, it would be toxic to drink and wouldn’t support microbial life. On Earth, salt-loving microorganisms thrive in the Dead Sea. However, Dead Sea salts are not perchlorate salts, and Mars’ surface water is far more briny than the Dead Sea — even more briny than Antarctica’s Don Juan Pond, where salinity is 44 percent.

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The saltiest pond on Earth. (Credit: NASA Earth Observatory image by Jesse Allen)

Along with hypothyroid conditions, perchlorate has also been implicated in aplastic anemia and agranulocytosis, conditions characterized by a life-threatening deficiency of blood cells. Perchlorate is particularly dangerous for infants dependent on lactating mothers; that’s enough of a concern on Earth, but especially alarming on a new world that interplanetary colonists might populate.

This means that we’ll have to take extreme precaution to remove perchlorate from Mars water and dirt, or from any crops that we grow in it. Dust will have to be kept from contaminating air circulating through life support systems. Future explores and colonists will have to do all of this, not only as they capture the perchlorate in order to reap its benefits, but also as they confront space radiation, physical deconditioning from low gravity, and other potential Martian threats to human health.

CATEGORIZED UNDER: Space & Physics, Top Posts
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These Experiments Are Building the Case to Terraform Mars

By Nathaniel Scharping | June 14, 2016 10:43 am
MarsTransitionV

An artist’s conception of what Mars could look like as it gradually becomes more habitable. (Credit: Daein Ballard/Wikimedia Commons)

Whether it’s extreme climate change, an impending asteroid impact, scientific curiosity or even space tourism, there are compelling reasons to think about calling Mars our second home. But before expanding humanity’s cosmic real estate holdings, scientists will need to make the Red Planet feel a little more like our blue marble.

That, in a nutshell, is the goal of researchers thinking about ways to terraform another planet.

Elon Musk, of Tesla and SpaceX fame, has suggested we nuke the polar ice caps on Mars to unlock liquid water and release clouds of CO2 that would thicken the atmosphere and warm the planet. This notion got some press last year when Major League Baseball player and amateur astrophysicist Jose Canseco tweeted: “By my calculations if we nuked the polar ice caps on Mars we would make an ocean of 36 feet deep across the whole planet,” thereby enshrining the idea in our popular imagination. Giant mirrors concentrating sunlight on the poles and smashing an entire moon into Mars also top the list of grandiose proposals to Earth-ify the Red Planet. Read More

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What Do the Stars Look Like from Mars?

By Eric Betz | June 10, 2016 1:32 pm
mars-stars

An artist’s concept of a meteor shower, as seen on Mars. (Credit: NASA/JPL-Caltech)

The Mars-like deserts of the American Southwest are some of Earth’s most iconic stargazing grounds. Far from pestering city lights and free from regular cloud cover, they provide a starry-skied sanctuary for lovers of the night.

So, it would stand to reason that the deserts of Mars itself would be even more idyllic. After all, there’s no light pollution and cloud cover is hard to come by.

And to some degree, that’s true. It doesn’t get much darker than nighttime on the Red Planet. And Mars’ atmosphere is so weak — just one percent of Earth’s — that the stars don’t twinkle. Read More

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How the Elements Got Their Names

By Mark Lorch, University of Hull | June 9, 2016 9:42 am
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(Credit: Antoine2K/Shutterstock)

The seventh row of the periodic table is complete, resplendent with four new names for the elements 113, 115, 117 and 118. The International Union of Pure and Applied Chemistry (the organization charged with naming the elements) has suggested these should be called nihonium (Nh); moscovium (Mc); tennessine (Ts) and oganesson (Og) and is expected to confirm the proposal in November.

The three former elements are named after the regions where they were discovered (and Nihonium references Nihon the Japanese name for Japan). And “oganesson” is named after the Russian-American physicist Yuri Oganessian, who helped discover them. Read More

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In Memory of the Spirit Rover

By Korey Haynes | May 26, 2016 3:04 pm
NASA_Mars_Rover

The Spirit rover explored the Red Planet for more than five years, well past its original mission lifetime. (Credit: NASA)

Five years ago, NASA officially ceased recovery efforts for the Spirit rover. They didn’t give up without a fight. The rover had been silent since March of 2010, more than a year earlier, and stationary since 2009, when it drove into a patch of soft martian soil.

With Spirit’s twin rover, Opportunity, driving merrily along to this day (though not without signs of aging), it’s tempting, in hindsight, to consider Spirit the disappointing sibling. Certainly it’s difficult not to dream about the wealth of images and data Spirit might have returned had it not become mired in a soft patch of martian soil.

But we would be ungrateful not to look back on what was still a spectacular science mission lifetime for Spirit. Let’s re-live some highlights.

Read More

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The First Moon Base Will Be Printed

By Morgan Saletta, University of Melbourne | May 17, 2016 1:59 pm
3-D printers building a moon base from materials harvested from the lunar surface.

3D Printers would scoop material from the lunar surface into bins and spit it out as building material. (Credit: Contour Crafting)

Planetary Resources, a company hoping to make asteroid mining into a trillion dollar industry, earlier this year unveiled the world’s first 3D printed object made from bits of an asteroid.

3D printing, and additive manufacturing processes more generally, have made many advances in recent years. Just a few years ago, most 3D printing was only used for building prototypes, which would then go on to be manufactured via conventional processes. But it’s now increasingly being used for manufacturing in its own right.

Nearly two years ago, NASA even sent a 3D printer to the International Space Station with the goal of testing how the technology works in micro-gravity. While the printer resembles a Star Trek replicator, it’s not quite that sophisticated yet; the objects it can print are small prototypes for testing.

The 3D printer used in the ISS. (Credit: Made In Space)

But 3D printed objects don’t have to be small. Entire houses have now been 3D printed, including out of renewable resources such as clay and earth.

And visionary architect Enrico Dini, a pioneer of 3D construction featured in the film The Man Who Prints Houses, isn’t thinking small, confessing:

What I really want to do is to use the machine to complete the Sagrada Familia. And to build on the moon.

Above and Beyond

NASA, the European Space Agency (ESA) and entrepreneurs aiming to jump-start human colonization of space see the 3D printing of large scale objects, including entire habitations, as a major enabling technology for the future of space exploration.

In 2013, a project led by the ESA used simulated lunar regolith – i.e. loose top soil – to produce a 1.5-ton hollow cell building block. It was conceived as part of a dome shelter for a lunar base that would also incorporate an inflatable interior structure. The project used a D-Shape printer using Enrico Dini’s company, Monolite.

The 1.5-ton building block produced as a demonstration. (Credit: ESA)

Since 2011, NASA has been funding similar research led by Professor Behrokh Khoshnevies at the University of Southern California. His team has been using a technology called contour crafting, which also has the goal of using 3D printing to construct entire space habitations from in situ resources.

After testing 3D printing in space, NASA has decided the technology is close to a tipping point. As part of a new program of public/private partnerships aimed at pushing emerging space capabilities over these tipping points, NASA has awarded a major contract to the Archinaut project.

Multi-dome lunar base being constructed, based on the 3D printing concept. Once assembled, the inflated domes are covered with a layer of 3D-printed lunar regolith by robots to help protect the occupants against space radiation and micrometeoroids. (Credit: ESA)

The project will see a 3D printer, built by Made in Space, mated with a robotic arm, built by Oceaneering Space Systems, with Northrup Grumman providing the control software and integration with the ISS systems.

The goal of the project is to provide an on-orbit demonstration of large, complex structure – in this case a boom for a satellite – sometime in 2018.

Archinaut is a technology platform that enables autonomous manufacture and assembly of spacecraft systems on orbit. (Credit: Made In Space)

Down to Earth

But 3D manufacturing is already changing the aerospace industry. Composites, for example, have become a commonly used material for a wide variety of applications.

But composites tend to suffer weakness between their laminating layers, which can lead to material failures in crucial components. 3D weaving, which deploys fibers on three axes, is set to revolutionize these materials and their performances.

Indeed, NASA is now using 3D woven quartz fiber compression pads for its Orion Space Vehicle and exploring the technology for use in other thermal protection surfaces.

But the ability to use in situ materials, both for fuel, water and construction whether on the moon, Mars, or asteroids has long been recognized as a crucial ability to enable human exploration of the solar system.

Contests such as last the 3D Printed Habitat Challenge, part of NASA’s Centennial Challenges, are an important element of an innovation strategy designed to push the envelope of technology, leveraging entrepreneurial spirit, scientific and technological know-how and design thinking in a bid to take human space exploration to the next level.

Mars Ice House cross section. (Credit: Space Exploration Architecture and Clouds AO)

The winning design, announced at the New York Makers Faire in September, was the Mars Ice House.

The Mars Ice House Habitat, which would be printed out of ice from relatively abundant water on Mars’ northern hemisphere, is a far cry from the bunker-like spaces frequently envisioned for Mars bases. The ice would provide ample radiation protection while creating a radiant, light filled space reminiscent of a cathedral.

Space exploration has always been associated with visionary fiction and grandiose plans, and it looks like 3D manufacturing and construction may finally bring the printed word to life.

 

This article was originally published on The Conversation. Read the original article.

CATEGORIZED UNDER: Space & Physics, Technology, Top Posts
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