Category: Space & Physics

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

CATEGORIZED UNDER: Space & Physics, Top Posts

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
MORE ABOUT: Mars, space exploration

These Experiments Are Building the Case to Terraform Mars

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

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

What Do the Stars Look Like from Mars?

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

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

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 (Mv); 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

CATEGORIZED UNDER: Space & Physics, Top Posts

In Memory of the Spirit Rover

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

CATEGORIZED UNDER: Space & Physics, Top Posts

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

If There’s Life on Mars, How Should We Treat It?

By Kelly Smith, Clemson University | May 12, 2016 11:19 am
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NASA’s Curiosity rover captured this image of the Kimberley formation on Mars. (Credit: NASA/JPL-Caltech)

NASA’s chief scientist recently announced that “…we’re going to have strong indications of life beyond Earth within a decade, and I think we’re going to have definitive evidence within 20 to 30 years.” Such a discovery would clearly rank as one of the most important in human history and immediately open up a series of complex social and moral questions. One of the most profound concerns is about the moral status of extraterrestrial life forms. Since humanities scholars are only just now beginning to think critically about these kinds of post-contact questions, naïve positions are common.

Take Martian life: we don’t know if there is life on Mars, but if it exists, it’s almost certainly microbial and clinging to a precarious existence in subsurface aquifers. It may or may not represent an independent origin – life could have emerged first on Mars and been exported to Earth. But whatever its exact status, the prospect of life on Mars has tempted some scientists to venture out onto moral limbs. Of particular interest is a position I label “Mariomania.”

Should We Quarantine Mars?

Mariomania can be traced back to Carl Sagan, who famously proclaimed

If there is life on Mars, I believe we should do nothing with Mars. Mars then belongs to the Martians, even if the Martians are only microbes.

Chris McKay, one of NASA’s foremost Mars experts, goes even further to argue that we have an obligation to actively assist Martian life, so that it does not only survives, but flourishes:

…Martian life has rights. It has the right to continue its existence even if its extinction would benefit the biota of Earth. Furthermore, its rights confer upon us the obligation to assist it in obtaining global diversity and stability.

To many people, this position seems noble because it calls for human sacrifice in the service of a moral ideal. But in reality, the Mariomaniac position is far too sweeping to be defensible on either practical or moral grounds.

Streaks down Martian mountains are evidence of liquid water running downhill – and hint at the possibility of life on the planet. (Credit: NASA/JPL/University of Arizona)

A Moral Hierarchy: Earthlings before Martians?

Suppose in the future we find that:

  1. There is (only) microbial life on Mars.
  2. We have long studied this life, answering our most pressing scientific questions.
  3. It has become feasible to intervene on Mars in some way (for instance, by terraforming or strip mining) that would significantly harm or even destroy the microbes, but would also be of major benefit to humanity.

Mariomaniacs would no doubt rally in opposition to any such intervention under their “Mars for the Martians” banners. From a purely practical point of view, this probably means that we should not explore Mars at all, since it is not possible to do so without a real risk of contamination.

Beyond practicality, a theoretical argument can be made that opposition to intervention might itself be immoral:

  • Humans beings have an especially high (if not necessarily unique) moral value and thus we have an unambiguous obligation to serve human interests.
  • It is unclear if Martian microbes have moral value at all (at least independent of their usefulness to people). Even if they do, it’s certainly much less than that of human beings.
  • Interventions on Mars could be of enormous benefit to humankind (for instance, creating a “second Earth”).
  • Therefore: we should of course seek compromise where possible, but to the extent that we are forced to choose whose interests to maximize, we are morally obliged to err on the side of humans.

Obviously, there are a great many subtleties I don’t consider here. For example, many ethicists question whether human beings always have higher moral value than other life forms. Animal rights activists argue that we should accord real moral value to other animals because, like human beings, they possess morally relevant characteristics (for instance, the ability to feel pleasure and pain). But very few thoughtful commentators would conclude that, if we are forced to choose between saving an animal and saving a human, we should flip a coin.

Simplistic claims of moral equality are another example of overgeneralizing a moral principle for rhetorical effect. Whatever one thinks about animal rights, the idea that the moral status of humans should trump that of microbes is about as close to a slam dunk as it gets in moral theory.

On the other hand, we need to be careful since my argument merely establishes that there can be excellent moral reasons for overriding the “interests” of Martian microbes in some circumstances. There will always be those who want to use this kind of reasoning to justify all manner of human-serving but immoral actions. The argument I outline does not establish that anyone should be allowed to do anything they want to Mars for any reason. At the very least, Martian microbes would be of immense value to human beings: for example, as an object of scientific study. Thus, we should enforce a strong precautionary principle in our initial dealings with Mars (as a recent debate over planetary protection policies illustrates).

For Every Complex Question, There’s a Simple, Incorrect Answer

Mariomania seems to be the latest example of the idea, common among undergraduates in their first ethics class, that morality is all about establishing highly general rules that admit no exception. But such naïve versions of moral ideals don’t long survive contact with the real world.

By way of example, take the “Prime Directive” from TV’s “Star Trek”:

…no Star Fleet personnel may interfere with the normal and healthy development of alien life and culture…Star Fleet personnel may not violate this Prime Directive, even to save their lives and/or their ship…This directive takes precedence over any and all other considerations, and carries with it the highest moral obligation.

Hollywood’s version of moral obligation can be a starting point for our real-world ethical discussion.

As every good trekkie knows, Federation crew members talk about the importance of obeying the prime directive almost as often as they violate it. Here, art reflects reality, since it’s simply not possible to make a one-size-fits-all rule that identifies the right course of action in every morally complex situation. As a result, Federation crews are constantly forced to choose between unpalatable options. On the one hand, they can obey the directive even when it leads to clearly immoral consequences, as when the Enterprise refuses to cure a plague devastating a planet. On the other hand, they can generate ad hoc reasons to ignore the rule, as when Captain Kirk decides that destroying a supercomputer running an alien society doesn’t violate the spirit of the directive.

Of course, we shouldn’t take Hollywood as a perfect guide to policy. The Prime Directive is merely a familiar example of the universal tension between highly general moral ideals and real-world applications. We will increasingly see the kinds of problems such tension creates in real life as technology opens up vistas beyond Earth for exploration and exploitation. If we insist on declaring unrealistic moral ideals in our guiding documents, we should not be surprised when decision makers are forced to find ways around them. For example, the U.S. Congress’ recent move to allow asteroid mining can be seen as flying in the face of the “collective good of mankind” ideals expressed in the Outer Space Treaty signed by all space-faring nations.

The solution is to do the hard work of formulating the right principles, at the right level of generality, before circumstances render moral debate irrelevant. This requires grappling with the complex trade-offs and hard choices in an intellectually honest fashion, while refusing the temptation to put forward soothing but impractical moral platitudes. We must therefore foster thoughtful exchanges among people with very different conceptions of the moral good in order to find common ground. It’s time for that conversation to begin in earnest.

The Conversation

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

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

How to Harvest Terawatts of Solar Power on the Moon

By David Warmflash | April 22, 2016 1:03 pm
luna-ring

(Credit: Shimzu)

Planet Earth isn’t the most ideal place for solar power to thrive. Sunsets and weather afford solar panels a significant amount of downtime.

But there’s a place not too far from here where the sun never stops shining.

A handful of researchers, and more recently the Japanese corporation Shimizu, have been gearing up to develop solar power on the moon.

Shimizu took off with the idea in 2013 in the aftermath of Japan’s 2011 Fukishima accident, which produced a political climate demanding alternatives to nuclear power plants. Shimizu’s plans call for beginning construction of a lunar solar power base as early as 2035. The solar array would be 250 miles wide and span the lunar circumference of 6,800 miles. They’re calling it the Luna Ring. Read More

Mercury Keeps Getting Weirder

By David Rothery, The Open University | March 11, 2016 11:58 am
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An image of Mercury via the MESSENGER spacecraft. This false-color image is enhanced to show the chemical, mineralogical and physical differences between the rocks that make up Mercury’s surface. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

For such a tiny planet, Mercury is a pretty big puzzle for researchers. NASA’s MESSENGER probe already has revealed that the planet is surprisingly rich in elements that easily evaporate from the surface, such as sulphur, chlorine, sodium and potassium. This is incredibly odd as these kind of substances most likely would disappear during a hot or violent birth – exactly the type of birth a planet so close to the sun, such as Mercury, would have had.

Scientists are also struggling to understand why Mercury is so dark and what its earliest planetary crust, created as the newly-formed planet cooled down, was made of. Research has now started to throw up answers – but these are raising a lot of new questions. Read More

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: solar system
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