15,000 Galaxies in One Image

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Astronomers have just assembled one of the most comprehensive portraits yet of the universe’s evolutionary history, based on a broad spectrum of observations by the Hubble Space Telescope and other space and ground-based telescopes.  Each of the approximately 15,000 specks and spirals are galaxies, widely distributed in time and space. (NASA, ESA, P. Oesch of the University of Geneva, and M. Montes of the University of New South Wales)

Here’s an image to fire your imagination: Fifteen thousand galaxies in one picture — sources of light detectable today that were generated as much as 11 billion years ago.

Of those 15,000 galaxies, some 12,000 are inferred to be in the process of forming stars.  That’s hardly surprising because the period around 11 billions years ago has been determined to be the prime star-forming period in the history of the universe.  That means for the oldest galaxies in the image, we’re seeing light that left its galaxy but three billion years after the Big Bang.

This photo mosaic, put together from images taken by the Hubble Space Telescope and other space and ground-based telescopes, does not capture the earliest galaxies detected. That designation belongs to a galaxy found in 2016 that was 420 million years old at the time it sent out the photons just collected. (Photo below.)

Nor is it quite as visually dramatic as the iconic Ultra Deep Field image produced by NASA in 2014. (Photo below as well.)

But this image is one of the most comprehensive yet of the history of the evolution of the universe, presenting galaxy light coming to us over a timeline up to those 11 billion years.  The image was released last week by NASA and supports an earlier paper in The Astrophysical Journal by Pascal Oesch of Geneva University and a large team of others.

And it shows, yet again, the incomprehensible vastness of the forest in which we are a tiny leaf.

Some people apparently find our physical insignificance in the universe to be unsettling.  I find it mind-opening and thrilling — that we now have the capability to not only speculate about our place in this enormity, but to begin to understand it as well.

The Ultra-Deep field composite, which contains approximately 10,000 galaxies.  The images were collected over a nine-year period.  {NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)} 

For those unsettled by the first image, here is the 2014 Ultra Deep Field image, which is 1/14 times the area of the newest image.  More of the shapes in this photo look to our eyes like they could be galaxies, but those in the first image are essentially the same.

In both images, astronomers used the ultraviolet capabilities of the Hubble, which is now in its 28th year of operation.

Because Earth’s atmosphere filters out much ultraviolet light, the space-based Hubble has a huge advantage because it can avoid that diminishing of ultraviolet light and provide the most sensitive ultraviolet observations possible.

That capability, combined with infrared and visible-light data from Hubble and other space and ground-based telescopes, allows astronomers to assemble these ultra deep space images and to gain a better understanding of how nearby galaxies grew from small clumps of hot, young stars long ago.

The light from distant star-forming regions in remote galaxies started out as ultraviolet. However, the expansion of the universe has shifted the light into infrared wavelengths.

These images, then,  straddle the gap between the very distant galaxies, which can only be viewed in infrared light, and closer galaxies which can be seen across a broad spectrum of wavelengths.

The farthest away galaxy discovered so far is called GN-z11 and is seen now as it was 13.4 billion years in the past.  That’s  just 400 million years after the Big Bang.

GN-z11 is surprisingly bright infant galaxy located in the direction of the constellation of Ursa Major. Thus NASA video explains much more:

The farthest away galaxy ever detected — GN-z11. {NASA, ESA, P. Oesch (Yale University, Geneva University), G. Brammer (STScI), P. van Dokkum (Yale University), and G. Illingworth (University of California, Santa Cruz)} 

 

Galaxy formation chronology, showing GN-z11 in context. Hubble spectroscopically confirmed the farthest away galaxy to date. {NASA, ESA, P. Oesch and B. Robertson (University of California, Santa Cruz), and A. Feild (STScI)}

In addition representing cutting-edge science — and enabling much more — these looks into the most distant cosmic past offer a taste of what the James Webb Space Telescope, now scheduled to launch in 2021, is designed to explore.  It will have greatly enhanced capabilities to explore in the infrared, which will advance ultra-deep space observing.

But putting aside the cosmic mysteries that ultra deep space and time astronomy can potentially solve, the images available today from Hubble and other telescopes are already more than enough to fire the imagination about what is out there and what might have been out there some millions or billions of years ago.

A consensus of exoplanet scientists holds that each star in the Milky Way galaxy is likely to have at least one planet circling it, and our galaxy alone has billions and billions of stars.  That makes for a lot of planets that just might orbit at the right distance from its host star to support life and potentially have atmospheric, surface and subsurface conditions that would be supportive as well.

A look these deep space images raises the question of how many of them also house stars with orbiting planets, and the answer is probably many of them.  All the exoplanets identified so far are in the Milky Way, except for one set of four so far.

Their discovery was reported earlier this year by Xinyu Dai, an astronomer at the University of Oklahoma, and his co-author, Eduardo Guerras.  They came across what they report are planets while using NASA’s Chandra X-ray Observatory to study the environment around a supermassive black hole in the center of a galaxy located 3.8 billion light-years away from Earth.

In The Astrophysical Journal Letters , the authors report the galaxy is home to a quasar, an extremely bright source of light thought to be created when a very large black hole accelerates material around it. But the researchers said the results of their study indicated the presence of planets in a galaxy that lies between Earth and the quasar.

Furthermore, the scientists said results suggest that in most galaxies there are hundreds of free-floating planets for every star, in addition to those which might orbit a star.

The takeaway for me, as someone who has long reported on astrobiology and exoplanets, is that it is highly improbable that there are no other planets out there where life occurs, or once occurred.

As these images make clear, the number of planets that exist or have existed in the universe is essentially infinite.  That no others harbor life seems near impossible.

 

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Back to the Future on the Moon

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There have been no humans on the surface of the moon since the Apollo program ended in 1972.  Now, in addition to NASA, space agencies in India, China, Russia, Japan and Europe and developing plans to land humans on the moon. (NASA/Robin Lee)

What does NASA’s drive to return to the moon have to do with worlds of exoplanets and astrobiology that are generally discussed here?  The answer is actually quite a lot.

Not so much about the science, although current NASA plans would certainly make possible some very interesting science regarding humans living in deep space, as well as some ways to study the moon, Earth and our sun.

But it seems especially important now to look at what NASA and others have in mind regarding our moon because the current administration has made a top priority of returning landers and humans to there, prospecting for resources on the moon and ultimately setting up a human colony on the moon.

This has been laid out in executive directives and now is being translated into funding for NASA (and commercial) missions and projects.

There are at least two significant NASA projects specific to the moon initiative now planned, developed and in some cases funded.  They are the placement of a small space station that would orbit the moon, and simultaneously a series of robotic moon landings — to be conducted by commercial ventures but carrying NASA and other instruments from international and other commercial partners.

The goal is to start small and gradually increase the size of the landers until they are large enough to carry astronauts.

And the same growth line holds for the overall moon mission.  The often-stated goal is to establish a colony on the moon that will be a signal expansion of the reach of humanity and possibly a significant step towards sending humans further into space.

A major shift in NASA focus is under way and, most likely in the years ahead, a shift in NASA funding.

Given the potential size and importance of the moon initiative — and its potential consequences for NASA space science — it seems valuable to both learn more about it.

 

Cislunar space is, generally speaking, the area region between the Earth and the moon. Always changing because of the movements of the two objects.

Development work is now under way for what is considered to be the key near-term and moon-specific project.  It used to be called the the Deep Space Gateway as part of the Obama administration proposal for an asteroid retrieval mission, but now it’s the Lunar Orbital Platform-Gateway (LOP-G.)

If built, the four-person space station would serve as a quasi-permanent outpost orbiting the moon that advocates say would enhance exploration and later commercial exploitation of the moon.  It would provide a training area and safe haven for astronauts, could become a center for moon, Earth and solar science, and could continue and expand the international cooperation nurtured on the International Space Station (ISS) project for several decades.

In its Gateway Memorandum, published last month, NASA and the administration also made clear that the station would have, as a central goal, geopolitical importance.

As stated in the memorandum, “the next step in human spaceflight is the establishment of U.S. preeminence in cislunar space through the operations and the deployment of a U.S.-led lunar orbital platform,  “Gateway.”  (“Cislunar space” is the region lying  between the Earth and the moon.)

The administration requested $500 million for planning the LOP-G project in fiscal 2019.  The first component to be built and hopefully launched into cislunar space under the plan is the “power and propulsion element.”

 

An artist version of a completed Gateway spaceport with the Orion capsule approaching. (NASA)

Five companies have put together proposals for the “PPE,” and NASA officials have said they are ready to move ahead with procurement.

During a March meeting of the NASA Advisory Council’s human exploration and operations committee, Michele Gates, director of the Power and Propulsion Element at NASA Headquarters, said the agency will be ready to move ahead with procurement of the module when the five industry proposals are completed.

Some of those companies had been involved in studies for the cancelled Asteroid Redirect Mission and Gates said, “Our strategy is to leverage all of the work that’s been done, including on the Asteroid Redirect Mission.”

Five different companies have contracts to design possible space station habitation modules as well.

So the plan has some momentum.  If all moves ahead as described, NASA will launch the components of the Gateway in the early to mid 2020s.  More than a dozen international agencies have voiced interest in joining the project, including European, Japanese, Canadian and other ISS partners.

As part of that outreach, an informal partnership agreement has already been signed with Roscosmos, the Russian space agency, with the possibility of using a future Russian heavy rocket to help build the station and ferry crew.

 

Astronaut John Young of the Apollo 16 mission on the moon. The primary goal of the NASA moon initiative is to return astronauts to the surface.(NASA)

The other NASA moon initiative involves an effort to send many robotic landers to the moon to look for potential water and fuel (hydrogen) to be collected for a cislunar and ultimately lunar economy.

NASA had worked for some time on what was called a Resource Prospector, a mission to study water ice and other volatiles at the lunar poles.  But this spring NASA Administrator Jim Bridenstine announced the Prospector was being cancelled because it was not suited to the what is called the new Exploration Campaign — NASA’s concept for a series of missions that will initially use small, commercially developed landers, followed by larger landers.

So the Prospector project is now considered “too limited in scope for the agency’s expanded lunar exploration focus,” the agency said in a statement. “NASA’s return to the moon will include many missions to locate, extract and process elements across bigger areas of the lunar surface.”

The agency also says it will rely on private companies to design and build the landers, as well as launching them into space.

So these are the out-of-the gate projects NASA has in mind for the moon. They, however, are hardly where the big money is going.  That is directed to the heavy rocket under development and construction for more than a decade (the Space Launch System, or SLS) and the Orion space capsule.

They are designed to be the main conduits to the Gateway and perhaps beyond some day, and they have been enormously costly to build — at least $22 billion to construct up through 2021, NASA officials told the Government Accounting Office in 2014. And that doesn’t include the more costly second SLS rocket scheduled for 2023 with a crew aboard.

What’s more, it is estimated to cost at least $1.5 billion to launch each SLS/Orion voyage in years ahead.

 

Astronauts go into an Orion capsule mock-up. The un-manned spacecraft is expected to be ready for launch in 2020. (NASA/ Bill Stafford and Roger Markowitz)

 

Another mock-up of the inside of the Orion crew module, which carries four astronauts and is scheduled to launch in 2023. It has 316 cubic feet of habitable space, compared with 210 cubic feet for the Apollo capsules. (NASA)

 

Since this column is primarily about space and origins science, I was drawn to the conference held late Feb. in Denver — billed as the Deep Space Gateway Concept Science Workshop.  The idea, surely, was to share and showcase what science might be achievable on the mini-space station.

As you might imagine, a major scientific focus was on the challenges to humans of living in deep space and techniques that might be used to mitigate problems. Abstracts included studies of the effects of radiation on astronauts, on drugs, on food, on the immune system and more.

NASA and others have studied for years radiation and micro-gravity effects on astronauts aboard the International Space Station, but conditions in a deep space environment would be quite a bit different.  Probably most importantly, astronauts aboard the Gateway would be exposed to much more dangerous radiation than those in the ISS because that low-Earth orbit station is protected by the Van Allen radiation belts.

There was also an intriguing proposal to study the ability of lunar regolith (the rock, dust and gravel on the surface) to shield growing plants on the station from radiation, and others on the role and usefulness of plants and micro-organisms in deep space.

Scientists also proposed many different ways to study the moon, the Earth and the sun.  Harley Thronson of NASA Goddard, one of the moderators of the conference, said that sun scientists seemed especially excited by the opportunities the Gateway could offer.

As far as I could tell, there was but one proposal that involved astrobiology or exoplanets.  It was a plan by scientists from SETI and NASA Ames to study Earth with a spectrometer as a way to understand and measure potential bio-markers on exoplanets.

So there’s undoubtedly good science to be done on a lunar space port regarding human space flight, the moon, the Earth and sun.

What I wonder is this:  Will this new, intense and costly lunar focus on the moon take away from what I like to think of as The Golden Age of Space Science — the unending breakthroughs of recent decades in understanding planets and distant moons in our solar system, detecting and characterizing the billions and billions of exoplanets out there,  as well as revealing the structure and history of the cosmos.

 

The Sombrero Galaxy, as imaged by the Hubble Space Telescope, NASA’s Flagship observatory of the 1990s. The James Webb Space Telescope is delayed but is expected to provide the same remarkable images and science as Hubble once it’s up and working.  WFIRST, the planned flagship observatory of the 2020s was cancelled by the administration earlier this year because of a NASA funding shortfall, but its fate remains undecided. (NASA)

I’m not thinking about today but about when costly NASA flagship space observatories or major planetary missions come up for approval, or non-approval, in the future.  Will the funding, and the deep interest, still be there?

Others more knowledgeable about the mechanics of space travel also criticize the Gateway as a costly detour from what long has been considered the main goal of space exploration — sending humans to Mars — and as redundant when it comes to accessing and studying the moon.

On a more encouraged note, a lunar station and lunar base could become part of a much larger space architecture that will allow for all kinds of advances in the decades ahead.  This is precisely the kind of build-out that Thronson, who is Senior Scientist for Advanced Astrophysics Mission Concepts at NASA Goddard and Chief Technologist for the Cosmic Origins and Physics of the Cosmos Program Offices, has been working towards for years.

Ever mindful of the uses of such a space architecture, he pointed out one potential use of a lunar space station that is seldom heard:  If a powerful new telescope in deep space needs repair or upgrading, he wrote in an email, there’s no way to get humans to it now.  The Hubble Space Telescope could be fixed because it was not in deep space and astronauts could get to it.

Thronson sees a potential parallel use for the Gateway, as he described in an email. “My astronomy colleagues, including myself, have been for many years advocating using a Gateway-type facility to assemble, repair, and upgrade the next generation (and beyond) of major astronomical missions. Nothing beats having a human on site, if there are complicated activities that need to be carried out.”

 

 

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Birth and Death: A Theory of Relativity

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Irving Kaufman in Truro, Massachusetts, when a still-young 89.

I hope you will indulge me in this foray into a very different look at the many worlds in which we live.

My father is being buried today.  It is no tragedy;  he lived to almost 97 and had a full life.  But still…

As all of you have no doubt experienced in one way or another, there is a huge disconnect between the emotions we feel individually about a newcomer to our world or a departing elder and the arrival and departure of those we don’t know at all.

The birth of a loved child is as glorious as most anything can be.  And yet it is, in the larger picture, totally banal.  I found this figure:  By 2011, an estimated 107,602,707,800 humans had been born since the emergence of the species.

Same with death.  The death of a loved elder is a profound event.  And yet it, too, is banal.  One hundred billion of those born have also died.

There are a handful of exceptions to this dual reality. These births and deaths (and lives) are not viewed as banal but as historically important.  You can pick your own people for that list, but I bet they will be a group of people both very good and very bad, many of them talented and all of them charismatic.

But for the rest of us,  a particular birth and death are of enormous importance to very few.  It’s a kind of background noise.

Why am I writing about this now?

Clearly because I’m grieving and trying to make sense of the suffering and passing of my father.

But also because that grief — and the absence of grief all around me in New York City where he lived — speaks to that weird relativity in the emotional universe.  When you look closely at what reality is, the picture is very different from how things may feel inside.

 

The Hubble Ultra-Deep Field (HUDF) is an image of a small region of space in the constellation Fornax, composited from Hubble Space Telescope data.  The image looks back approximately 13 billion years (between 400 and 800 million years after the Big Bang) and will be used to search for galaxies that existed at that time. (NASA)

This is a dichotomy I’ve had to embrace as I learn and write about the cosmos.  Our human view of the world is, well, often quite lacking in perspective.

Our sense of time is another example.  We humans live within a story line where a life of 97 years is a very long one.  Although there are an increasing number of long-lived people — almost two million above age 90 in the United States — they remain a tiny percentage of the population.

In terms of Earth’s 4.5 million years of geological time,  my father’s 96 years is less than a blip.  And in astronomical time — the 13.7 billion years of the universe — they are completely inconsequential.

Our human lifetimes matter so much to us. But in the reality of time and space as they truly exist,  those lives mean virtually nothing.  Yet we persist in our great joys and sorrows.  “All the world’s a stage and all the men and women merely players,” wrote one of those people whose name and legend does live on. “They have their exits and their entrances, and one man in his time plays many parts…” I think my father would appreciate this stepped-back approach to his passing.

My mother, Mabel Kaufman, as drawn by her young husband in the late 1930s.  She died in 2006.

He was born poor in the South Bronx and became a soldier, student, artist, professor, poet and voracious reader.  His background included virtually no science study, but as I wrote more about space and life origins, he found those subjects to be increasingly interesting.  (They were a welcome reprieve for me from the political discussions he was inclined to wage in a take-no-prisoners style.)

He was not a religious man, but he did enjoy thinking and reading about subjects ranging from the beginning of the cosmos to theories of quantum life. I don’t think he would ever use this word, but he sought a kind of cosmic transcendence.

This was especially so after the passing of his wife of 63 years.  He was nearly crushed by his grief, but he gradually put together a life that continued with stubborn and hopefully satisfying independence for 11 years.

He told me for several years that he didn’t fear death.  He didn’t want to die and went to many doctors to try to keep going.  But he said he was ready to accept the end, and in his final weeks and days I came to see that he was  — especially as he lost his treasured independence and endured a not inconsiderable amount of suffering.

He slowly left after a week of refusing almost all food and water.  I’m told it’s a kind of animal path to dying. (No disrespect here, as we are animals, of course.)  And I think such a path is no tragedy, especially given his good fortune to have had almost 97 years on Earth.

Irv Kaufman as a young art professor at the University of Michigan.

I wrote a column early in my tenure at Many Worlds about Einstein and his ideas about “cosmic religion.” In it, I wrote about that part of Einstein’s thinking that gets less attention than it seems to deserve, to me at least.  And as I was thinking about my father’s passing, Einstein’s thoughts on cosmic religion came back to me.

No god, no unresolvable mysteries, no dogma.  Instead the wonderful and punishing laws of nature and the cosmos, and our good fortune to have some time living in them as human beings.  A kind of clear-eyed transcendence without all the religious trappings.

Thoughts of clear-eyed transcendence brought back to mind the most searing and surprising death and aftermath that I’ve witnessed.  When I was a reporter at The Philadelphia Inquirer, a charming young woman and her reporter husband were finally going to have a long-desired baby.  Well into the pregnancy, as I remember it, the woman starting getting very sick and was ultimately diagnosed with a fast-spreading cancer.

It was brutal, but she hung on and gave birth.  And then a few days later she died.

The entire Inquirer staff came to her funeral, and her husband got up to speak.  None of us knew what to expect, what someone in his place could possibly say.

But speak he did, and what he had to say was powerfully moving and instructive.  Yes, he had felt despair and anger at the awful turn of events, and, yes, what faith he had was shattered.

Then he spoke as if transported about the unexpected understanding that had come to him.

The death was an absolute tragedy and hideously unfair.  But out of it had come a beautiful, healthy boy.  Despite the horrible twist of fate, something precious had arrived.  The mother’s strength and grit had allowed a longed-for baby to survive.

And the husband ended with this reality lost in the grief:  had his wife not been pregnant, she still would have died of cancer. But she would have died without a lovely child delivered to the world.

Grief and joyful transcendence. There was not a dry eye in the huge crowd and not a heart that had not been lifted.

My father’s death will effect far fewer people than the one I just described.  The emotional punch of his passing has less force because he lived fully and because so many of his contemporaries are gone.

But the emotional dichotomy is still there and cries out for transcendence.  Each life is so important and yet so unimportant.  How do we make sense of that?

 

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How to Give Mars an Atmosphere, Maybe

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The Many Worlds site has been down for almost two weeks following the crash of the server used to publish it.  We never expected it would take quite this long to return to service, but now we are back with a column today and another one for early next week.

An artist rendering of what Mars might look like over time if efforts were made to give it an artificial magnetic field to then enrich its atmosphere and made it more hospitable to human explorers and scientists. (NASA)

Earth is most fortunate to have vast webs of magnetic fields surrounding it. Without them, much of our atmosphere would have been gradually torn away by powerful solar winds long ago, making it unlikely that anything like us would be here.

Scientists know that Mars once supported prominent magnetic fields as well, most likely in the early period of its history when the planet was consequently warmer and much wetter. Very little of them is left, and the planet is frigid and desiccated.

These understandings lead to an interesting question: if Mars had a functioning magnetosphere to protect it from those solar winds, could it once again develop a thicker atmosphere, warmer climate and liquid surface water?

James Green, director of NASA’s Planetary Science Division, thinks it could. And perhaps with our help, such changes could occur within a human, rather than an astronomical, time frame.

In a talk at the NASA Planetary Science Vision 2050 Workshop at the agency’s headquarters, Green presented simulations, models, and early thinking about how a Martian magnetic field might be re-constituted and the how the climate on Mars could then become more friendly for human exploration and perhaps communities.

It consisted of creating a “magnetic shield” to protect the planet from those high-energy solar particles. The shield structure would consist of a large dipole—a closed electric circuit powerful enough to generate an artificial magnetic field.

Simulations showed that a shield of this sort would leave Mars in the relatively protected magnetotail of the magnetic field created by the object. A potential result: an end to largescale stripping of the Martian atmosphere by the solar wind, and a significant change in climate.

“The solar sytstem is ours, let’s take it,” Green told the workshop. “And that, of course, includes Mars. But for humans to be able to explore Mars, together with us doing science, we need a better environment.”

 

An artificial magnetosphere of sufficient size generated at L1 – a point where the gravitational pull of Mars and the sun are at a rough equilibrium — allows Mars to be well protected by what is known as the magnetotail. The L1 point for Mars is about 673,920 miles (or 320 Mars radii) away from the planet. In this image, Green’s team simulated the passage of a hypothetical extreme Interplanetary Coronal Mass Ejection at Mars. By staying inside the magnetotail of the artificial magnetosphere, the Martian atmosphere lost an order of magnitude less material than it would have otherwise. (J. Green)

Is this “terraforming,” the process by which humans make Mars more suitable for human habitation? That’s an intriguing but controversial idea that has been around for decades, and Green was wary of embracing it fully.

“My understanding of terraforming is the deliberate addition, by humans, of directly adding gases to the atmosphere on a planetary scale,” he wrote in an email.

“I may be splitting hairs here, but nothing is introduced to the atmosphere in my simulations that Mars doesn’t create itself. In effect, this concept simply accelerates a natural process that would most likely occur over a much longer period of time.”

What he is referring to here is that many experts believe Mars will be a lot warmer in the future, and will have a much thicker atmosphere, whatever humans do. On its own, however, the process will take a very long time.

To explain further, first a little Mars history.

Long ago, more than 3.5 billion years in the past, Mars had a much thicker atmosphere that kept the surface temperatures moderate enough to allow for substantial amounts of surface water to flow, pool and perhaps even form an ocean. (And who knows, maybe even for life to begin.)

But since the magnetic field of Mars fell apart after its iron inner core was somehow undone, about 90 percent of the Martian atmosphere was stripped away by charged particles in that solar wind, which can reach speeds of 250 to 750 kilometers per second.

Mars, of course, is frigid and dry now, but Green said the dynamics of the solar system point to a time when the planet will warm up again.

 

James Green, the longtime director of NASA’s Planetary Science Division. (NASA)

 

He said that scientists expect the gradually increasing heat of the sun will warm the planet sufficiently to release the covering of frozen carbon dioxide at the north pole, will start water ice to flow, and will in time create something of a greenhouse atmosphere. But the process is expected to take some 700 millon years.

“The key to my idea is that we now know that Mars lost its magnetic field long ago, the solar wind has been stripping off the atmosphere (in particular the oxygen) ever since, and the solar wind is in some kind of equilibrium with the outgassing at Mars,” Green said. (Outgassing is the release of gaseous compounds from beneath the planet’s surface.)

“If we significantly reduce the stripping, a new, higher pressure atmosphere will evolve over time. The increase in pressure causes an increase in temperature. We have not calculated exactly what the new equilibrium will be and how long it will take.”

The reason why is that Green and his colleagues found that they needed to add some additional physics to the atmospheric model, dynamics that will become more important and clear over time. But he is confident those physics will be developed.

He also said that the European Space Agency’s Trace Gas Orbiter now circling Mars should be able to identify molecules and compounds that could play a significant role in a changing Mars atmosphere.

So based on those new magnetic field models and projections about the future climate of Mars, when might it be sufficiently changed to become significantly more human friendly?

Well, a relatively small change in atmospheric pressure can stop an astronaut’s blood from boiling, and so protective suits and clothes would be simpler to design. But the average daily range in temperature on Mars now is 170 degrees F, and it will take some substantial atmospheric modification to make that more congenial.

Green’s workshop focused on what might be possible in the mid 21st century, so he hopes for some progress in this arena by then.

 

This image combines depicts an orbital view of the north polar region of Mars, based on data collected from two instruments aboard NASA’s Mars Global Surveyor, depicts an orbital view of the north polar region of Mars. About 620 miles across, the white sections are primarily water ice. Frozen carbon dioxide accumulates as a comparatively thin layer about one meter thick on the north cap in the northern winter only. NASA/JPL-Caltech/MSSS

 

One of many intriguing aspects of the paper is its part in an NASA effort to link fundamental models together for everything from predicting global climate to space weather on Mars.

The modeling of a potential artificial magnetosphere for Mars relied, for instance, on work done by NASA heliophysics – the quite advanced study of our own sun.

Chuanfei Dong, an expert on space weather at Mars, is a co-author on the paper and did much of the modeling work. He is now a postdoc at Princeton University, where he is supported by NASA.

He used the Block-Adaptive-Tree Solar-Wind Roe-Type Upwind Scheme (BATS-R-US) model to test the potential shielding effect of an artificial magnetosphere, and found that it was substantial when the magnetic field created was sufficiently strong.  Substantial enough, in fact, to greatly limit the loss of Martian atmosphere due to the solar wind.

As he explained, the artificial dipole magnetic field has to rotate to prevent the dayside reconnection, which in turn prevents the nightside reconnection as well.

If the artificial magnetic field does not block the solar winds properly, Mars could lose more of its atmosphere. That why the planet needs to be safely within the magnetotail of the artificial magnetosphere.

In their paper, the authors acknowledge that the plan for an artificial Martian magnetosphere may sound “fanciful,” but they say that emerging research is starting to show that a miniature magnetsphere can be used to protect humans and spacecraft.

In the future, they say, it is quite possible that an inflatable structure can generate a magnetic dipole field at a level of perhaps 1 or 2 Tesla (a unit that measures the strength of a magnetic field) as an active shield against the solar wind. In the simulation, the magnetic field is about 1.6 times strong than that of Earth.

 

A Mars with a magnetic field and consequently a thicker atmosphere would not likely be particularly verdant anytime soon. But it might make a human presence there possible.

 

As a summary of what Green and others are thinking, here is the “results” section of the short paper:

“It has been determined that an average change in the temperature of Mars of about 4 degrees C will provide enough temperature to melt the CO2 veneer over the northern polar cap.

“The resulting enhancement in the atmosphere of this CO2, a greenhouse gas, will begin the process of melting the water that is trapped in the northern polar cap of Mars. It has been estimated that nearly 1/7th of the ancient ocean of Mars is trapped in the frozen polar cap. Mars may once again become a more Earth-like habitable environment.

The results of these simulations will be reviewed (with) a projection of how long it may take for Mars to become an exciting new planet to study and to live on.”

 

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Messy Chemistry, Evolving Rocks, and the Origin of Life

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Ribosomes are life’s oldest and most universal assembly of molecules. Today’s ribosome converts genetic information (RNA) into proteins that carry out various functions in an organism. A growing number of scientists are exploring how earliest components of life such as the ribosome came to be. They’re making surprising progress, but the going remains tough.

 

Noted synthetic life researcher Steven Benner of Foundation for Applied Molecular Evolution (FfAME) is fond of pointing out that gooey tars are the end product of too many experiments in his field.  His widely-held view is that the tars, made out of chemicals known to be important in the origin of life, are nonetheless a dead end to be avoided when trying to work out how life began.

But in the changing world of origins of life research, others are asking whether those messy tars might not be a breeding ground for the origin of life, rather than an obstacle to it.

One of those is chemist and astrobiologist Irena Mamajanov of the Earth-Life Science Institute (ELSI)  in Tokyo.  As she recently explained during an institute symposium, scientists know that tar-like substances were present on early Earth, and that she and her colleagues are now aggressively studying their potential role in the prebiotic chemical transformations that ultimately allowed life to emerge out of non-life.

“We call what we do messy chemistry, and we think it can help shed light on some important processes that make life possible.”

Irena Mamajanov of the Earth-Life Science Institute (ELSI) in Tokyo was the science lead for a just completed symposium on emerging approaches to the origin of life question. (Credit: Nerissa Escanlar)

It stands to reason that the gunky tar played a role, she said, because tars allow some essential processes to occur:  They can concentrate compounds, it can encapsulate them, and they could provide a kind of primitive (messy) scaffolding that could eventually evolve into the essential backbones of a living entity.

“Scientists in the field have tended to think of the origin of life as a process going from simple to more complex, but we think it may have gone from very complex — messy — to more structured.”

Mamajanov is part of an unusual Japanese and international group gathered at (ELSI), a relatively new site on the campus of the Tokyo Institute of Technology. It is dedicated to origin of life and origin of Earth study, with a mandate to be interdisciplinary and to think big and outside the box.

ELSI just completed its fifth annual symposium, and it brought together researchers from a wide range of fields to share their research on what might have led to the emergence of life.  And being so interdisciplinary, the ELSI gathering was anything but straight and narrow itself.

There was talk of the “evolution” of prebiotic compounds; of how the same universal 30 to 50 genes can be found in all living things from bacteria to us; of the possibility that the genomes of currently alive microbes surviving in extreme environments provide a window into the very earliest life; and even that evolutionary biology suggests that life on other Earth-like planets may well have evolved to form rather familiar creatures.

Except for that last subject, the focus was very much on ways to identify the last universal common ancestor (LUCA), and what about Earth made life possible and what about life changed Earth.

 

Artist rendering of early Earth on a calm day.  Scientists are trying to understand the many and complex geochemical processes that led to the emergence of life from non-life.

 

Scientific interest in the origin of life on Earth (and potentially elsewhere) tends to wax and wane, in large part because the problem is so endlessly complex.  It’s one of the biggest questions in science, but some say that it will never be fully answered.

But there has been a relatively recent upsurge in attention being paid and in funding for origin of life researchers.

The Japanese government gave $100 million to build a home for ELSI and support it for ten years, the Simons Foundation has donated another $100 million for an origins of life institute at Harvard, the Templeton Foundation has made numerous origin of life grants and, as it has for years, the NASA Astrobiology Institute has funded researchers.  Some of the findings and theories are most intriguing and represent a break of sorts from the past.

For some decades now, the origins of life field has been pretty sharply divided.  One group holds that life began when metabolism (a small set of reactions able to harness and transform energy ) arose spontaneously; others maintain that it was the ability of a chemical system to replicate itself (the RNA world) that was the turning point.  Metabolism First versus the RNA First, plus some lower-profile theories.

In keeping with its goal of bringing scientists and disciplines together and to avoid as much origin-of-life dogma as possible, Mamajanov sees their “messy chemistry” approach as a third way and a more non-confrontational approach.  It’s not a model for how life began per se, but one of many new approaches designed to shed light and collect data about those myriad processes.

“This division in the field is hurting science because people are not talking to each other ,” she said.  “By design we’re not in one camp or another.”

Loren Williams of Georgia tech

Another speaker who exemplified that approach was Loren Williams of Georgia Tech, a biochemist whose lab studies the genetic makeup of those universal 30 to 50 ribosomes (a complex molecule made of RNA molecules and proteins that form a factory for protein synthesis in cells.)  He was principal investigator for the NASA Astrobiology Institute’s Georgia Tech Center for Ribosome Adaptation and Evolution from 2009-2014.

His goal is to collect hard data on these most common genes, with the inference that they are the oldest and closest to LUCA.

“What becomes quickly clear is that the models of the origin of life don’t fit the data,” he said. “What the RNA model predicts, for instance, is totally disconnected from this data.  So what happens with this disconnect?  The modelers throw away the data.  They say it doesn’t relate.  Instead, I ignore the models.”

A primary conclusion of his work is that early molecules — rather like many symbiotic relationships in nature today — need each other to survive.  He gave the current day example of the fig wasp, which spends its larval stage in a fig, then serves as a pollinator for the tree, and then survives on the fruit that appears.

He sees a parallel “mutualism” in the ribosomes he studies.  “RNA is made by protein; all protein is made by RNA,” he said.  It’s such a powerful concept for him that he wonders if  “mutualism” doesn’t define a living system from the non-living.

 

These stromatolites, wavelike patterns created by bacteria embedded in sediment, are 3.7 billion years old and may represent the oldest life on the planet. Photo by Allen Nutman

 

Stromatolites, sedimentary structures produced by microorganisms,  today at Shark Bay, Australia. Remarkably, the life form has survived through billions of years of radical transformation on Earth, catastrophes and ever-changing ecological dynamics.

 

A consistent theme of the conference was that life emerged from the geochemistry present in early Earth.  It’s an unavoidable truth that leads down some intriguing pathways.

As planetary scientist Marc Hirschmann of the University of Minnesota reported at the gathering, the Earth actually has far less carbon, oxygen, nitrogen and other elements essential for life than the sun, than most asteroids, than even interstellar space.

Since Earth was initially formed with the same galactic chemistry as those other bodies and arenas, Hirschmann said, the story of how the Earth was formed is one of losing substantial amounts of those elements rather than, as is commonly thought, by gaining them.

The logic of this dynamic raises the question of how much of those elements does a planet have to lose, or can lose, to be considered habitable.  And that in turn requires examination of how the Earth lost so much of its primordial inheritance — most likely from the impact that formed the moon,  the resulting destruction of the early Earth atmosphere, and the later movement of the elements into the depths of the planet via plate tectonics. It’s all now considered part of the origins story.

And as argued by Charley Lineweaver, a cosmologist with the Planetary Science Institute and the Australian National University, it has become increasingly difficult to contend that life on other planets is anything but abundant, especially now that we know that virtually all stars have planets orbiting them and that many billions of those planets will be the size of Earth.

Other planets will have similar geochemical regimes and some will have undergone events that make their distribution of elements favorable for life.  And as described by Eric Smith, an expert in complex systems at ELSI and the Santa Fe Institute, the logic of physics says that if life can emerge then it will.

Any particular planetary life may not evolve beyond single cell lifeforms for a variety of reasons, but it will have emerged.  The concept of the “origin of life” has taken on some very new meanings.

 

ELSI was created in 2012 after its founders won a World Premier International Research Center Initiative grant from the Japanese government. The WPI grant is awarded to institutes with a research vision to become globally competitive centers that can attract the best scientists from around the world to come work in Japan.

The nature and aims of ELSI and its companion group the ELSI Origins Network (EON) strike me as part of the story.  They break many molds.

The creators of ELSI, both Japanese and from elsewhere, say that the institute is highly unusual for its welcome of non-Japanese faculty and students.  They stay for years or months or even weeks as visitors.

While ELSI is an government-funded institute with buildings, professors, researchers and a mission (to greatly enhance origin of life study in Japan), EON is a far-flung collection of top international origins scientists of many disciplines.  Their home bases are places like Princeton’s Institute for Advanced Study, Harvard, Columbia, Dartmouth, Caltech and the University of Minnesota, among others in the U.S., Europe and Asia.  NASA officials also play a supporting, but not financial, role.

ELSI postdocs and other students live in Tokyo, while the EON fellows spend six months at ELSI and six months at home institutions.  All of this is in the pursuit of scientific collaboration, exposing young scientists in one field related to origins to those in another, and generally adding to global knowledge  about the sprawling subject of origins of life.

Jim Cleaves, of ELSI and the Institute for Advanced Study,  is the director of EON and an ambassador of sorts for its unusual mission.  He, and others at the ELSI symposium, are eager to share their science and want young scientists interested in the origins of life to know there are many opportunities with ELSI and EON for research, study and visitorships on the Tokyo campus.

 

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