Breakthrough Findings on Mars Organics and Mars Methane

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The Curiosity rover on Mars takes a selfie at a site named Mojave. Rock powdered by the rover drill system and then intensively heated rock and then heated to as much as 800 degrees centigrade produced positive findings for long-sought organics. (NASA/JPL-Caltech/MSSS.)

A decades-long quest for incontrovertible and complex Martian organics — the chemical building blocks of life — is over.

After almost six years of searching, drilling and analyzing on Mars, the Curiosity rover team has conclusively detected three types of naturally-occurring organics that had not been identified before on the planet.

The Mars organics Science paper, by NASA’s Jennifer Eigenbrode and much of the rover’s Sample Analysis on Mars (SAM) instrument team, was twinned with another paper describing the discovery of a seasonal pattern to the release of the simple organic gas methane on Mars.

This finding is also a major step forward not only because it provides ground truth for the difficult question of whether significant amounts of methane are in the Martian atmosphere, but equally important it determines that methane concentrations appear to change with the seasons. The implications of that seasonality are intriguing, to say the least.

In an accompanying opinion piece in Science, Inges Loes ten Kate of Utrecht University in  Netherlands wrote of the two papers: “Both these findings are breakthroughs in astrobiology.”

The clear conclusion of these (and other) recent findings is that Mars is not a “dead” planet where little ever changes.  Rather, it’s one with cycles that appear to produce not only methane but also sporadic surface water and changing dune formations.

Remains of 3.5 billion-year old lake that once filled Gale Crater. NASA scientists concluded early in the Curiosity mission that the planet was habitable long ago based on the study of mudstone remains like these. (NASA/JPL-Caltech/MSSS)

Finding organic compounds on Mars has been a prime goal of the Curiosity rover mission.

Those carbon-based compounds surely fall from the sky on Mars, as they do on Earth and everywhere else, but identifying them has proven illusive.

The consequences of that non-discovery have been significant.  Going back to the Viking missions of 1976, scientists concluded that life was not possible on Mars because there were no organics, or none that were detected.

Jen Eigenbrode, research astrobiologist at NASA’s Goddard Space Flight Center. (NASA/W. Hrybyk)

But the reasons for the disappearing organics are pretty well understood.  Without much of an atmosphere to protect it, the Martian surface is bombarded with ultraviolet radiation, which can destroy organic compounds.  Or, in the case of the samples discovered by the SAM team, large organic macromolecules — the likes of proteins, membranes and DNA — are broken up into much smaller pieces.

That’s what the team found, Eigenbrode told me. The organics were probably preserved, she said, because of exceptionally high levels of sulfur present in that part of Gale Crater.

The organics, extracted from mudstone at the Mojave and Confidence Hill sites, had bonded tightly with ancient non-organic material.  The organic material was freed to be collected as gas only after being exposed to temperatures of more than 500 to 800 centigrade in the SAM oven.

“This material was buried for billions of years and then exposed to extreme surface conditions, so there’s a limit to what we can learn about.  Did it come from life?  We don’t know.

“But the fact we found the organic carbon adds to the habitability equation.  It was in a lake environment that we know could have supported life.  Organics are things that organisms can eat.”

It will take different kinds of instruments and samples from drilling deeper into the extreme Martian surface to answer the question of whether the organics came from living microbes.  But for Eigenbrode, future answers of either “yes” or “no” are almost equally interesting.

Finding clear signs of early Martian life would certainly be hugely important, she said.  But a conclusion that Mars never had life — although it had conditions some 3.5 to 3.8 billion years ago quite similar to conditions on Earth at that time — raises the obvious question of “why not?”

NASA’s Curiosity rover raised robotic arm with drill pointed skyward while exploring Vera Rubin Ridge at the base of Mount Sharp inside Gale Crater. This navcam camera mosaic was stitched from raw images taken on Sol 1833, Oct. 2, 2017 and colorized. (NASA/JPL-Caltech/Ken Kremer, Marco Di Lorenzo)

Organic molecules are the building blocks of all known life on Earth, and consist of a wide variety of molecules made primarily of carbon, hydrogen, and oxygen atoms. However, organic molecules can also be made by chemical reactions that don’t involve life.

Examples of non-biological sources include chemical reactions in water at ancient Martian hot springs or delivery of organic material to Mars by interplanetary dust or fragments of asteroids and comets.

It needs to be said that today’s Mars organics announcement was not the first we have heard.  In 2014, a NASA team reported the presence of chlorine-based organics in Sheepbed mudstone at Yellowknife Bay, the first ancient Mars lake visited by Curiosity.

That work, led by NASA Goddard scientists Caroline Freissinet and Daniel Glavin and published in the Journal of Geophysical Research, focused on signatures from unusual organics not seen naturally on Earth.

The organics were complex and made entirely of Martian components, the paper reported.  But because they combined chlorine with the organic hydrocarbons, they are not considered to be as “natural” as the discovery announced today.

And when it comes to organics on Mars, the complicated history of research into the presence of the gas methane (a simple molecule that consists of carbon and hydrogen) also shows the great challenges involved in making these measurements on Mars.

By measuring absorption of light at specific wavelengths, the tunable laser spectrometer on Curiosity measures concentrations of methane, carbon dioxide and water vapor in the Martian atmosphere. (NASA)

 

The gold-plated Sample Analysis on Mars contains three instruments that make the measurements of organics and methane.  (NASA/Goddard Space Flight Center)

The second Science paper, authored by Chris Webster of NASA’s Jet Propulsion Lab and colleagues, reports that the gas methane has been detected regularly in recent years, with surprising seasonality.

“The history of Mars methane has been frustrating, with reports of some large plumes and spikes detected, but none have been repeatable.  It’s almost like they’re random,” he told me.  “But now we can see a large seasonal cycle in the background of these detections, and that’s extremely important.”

Over three Mars years, or almost five Earth years, Webster said there have been significant increases in methane detected during the summer, and especially the late summer. That tripling of the methane counts is considered too great to be random, especially since the count declines as predicted after the summer ends.

No definite explanation of why this happens has emerged yet, but one theory has been embraced by some scientists.

While it is still cold in the Martian summer, it can get warm enough where the sun shines directly on a collection of ice for some melting to occur.  And that melting, the paper reports, could provide an escape valve for methane collected long ago under the surface.  The process is termed “microseepage.”

 

This illustration shows the ways in which methane from the subsurface might find its way to the
surface where its release could produce the large seasonal variation in the atmosphere
as observed by Curiosity. Potential methane sources include byproducts from organisms alive or long dead, ultraviolet degradation of organics, or water-rock chemistry; and its losses include atmospheric photochemistry and surface reactions. Seasons refer to the northern hemisphere. The plotted data is from Curiosity’s TLS-SAM instrument, and the curved line through the data is to aid the eye. (NASA/JPL-Caltech)

Methane is a crucial organic in astrobiology because most of that gas found on Earth comes from biology, although various non-biological processes can produce methane as well.

Today’s paper by Webster et al is the third in Science on Mars methane as measured by Curiosity, and it is the first to find a seasonal pattern.  The first paper, in 2013,  actually reported there was no methane measured in early runs, a conclusion that led to push-back from many of those working in the field.

While the Mars methane results released today are being described as a “breakthrough,” they follow closely the findings of a Science paper in 2009 by Michael Mumma and Geronimo Villanueva, both at NASA Goddard.

The two reported then similar findings of plumes of methane on Mars, of a seasonality associated with their distribution, and a similar conclusion that the methane probably was coming from subsurface reservoirs.  Like Webster et al, Mumma and Villanueva said they were unable to determine if the source of methane was biological or geological.

The methane levels in the plumes they found were considerably higher than detected so far by Curiosity, but what they were detecting was quite different.  Using ground-based telescopes, they detected the high concentrations in two specific areas over a number of years, while Curiosity is measuring methane levels that are more global or regional.

Red areas indicate where in 2003 ground-based observers detected concentrations of methane in the Martian atmosphere, measured in parts per billion (ppb).  (NASA / M. Mumma & others)

Just as Webster was criticized for his initial paper saying there was no methane detected on Mars, the Mumma team also got sharp questions about their methodology and conclusions.  This grew as their numerous follow-up efforts to detect the Mars methane proved unsuccessful.

But now Webster says the Curiosity findings have essentially “confirmed” what Mumma and Villanueva reported nine years ago.

Still, the Curiosity results are a breakthrough because they were made on Mars rather than through a telescope. Mumma, who described the new Curiosity results as “satisfying,” agreed that they were a major step forward.

“This is how science works,” he said.  “We do our work and put out our papers and other scientists react.  We take it all in and make changes if needed.  But the big changes come when new, and maybe different, data is presented.”

And that’s exactly what will be happening soon regarding methane on Mars.  Beginning early this year, the European/Russian Trace Gas Orbiter (TGO) has been collecting data specifically on Mars gases including methane.  Unlike previous Mars methane campaigns, this one can potentially determine whether the methane being released from below the surface was formed by biology or geology — although not without great difficulty.

Mumma, who is part of that TGO team, said the first release of information is due in the fall.

 

 

 

 

 

 

 

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A Reprieve for Space Science?

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View of WFIRST focusing on supernova SN1995E in NGC 2441. The high-priority but embattled space telescope would, if congressional support continues, add greatly to knowledge about dark energy and dark matter, supernovae, and exoplanets.  (NASA)

A quick update on a recent column about whether our “golden age” of space science and discovery was in peril because of cost overruns and Trump administration budget priorities that emphasized human space travel over science.

The 2018 omnibus spending bill that was passed Wednesday night by the House of Representatives and Thursday night by the Senate represents a major push back against the administration’s earlier NASA budget proposals.  Not only would the agency receive $1.6 billion more funding than proposed by the administration, but numerous projects that had been specifically eliminated in that proposal are back among the living.

They include four Earth science satellites, a lander to accompany the Europa Clipper mission to that potentially habitable moon and, perhaps most important, the Wide Field Infrared Survey Telescope (WFIRST) space telescope.

Funding for that mission, which was the top priority of the space science community and the National Academy of Sciences for the 2020s, was eliminated in the proposed 2019 Trump budget, but WFIRST received $150 million in the just-passed omnibus bill.

A report accompanying the omnibus bill is silent about the proposed cancellation and instructs NASA to provide to Congress in 60 days a cost estimate for the full life cycle of the mission, including any additions that might be needed.  So there appears to be a strong congressional desire to see WFIRST launch and operate.

Still hanging fire is the fate of the James Webb Space Telescope, which has fallen behind schedule again and is in danger of crossing the $8 billion cap put into place by Congress in 2011.  NASA officials said this week that they will soon announce their determination about whether a breach of the program’s cost cap will occur as a result of further delays.

NASA has a fleet of 18 Earth science missions in space, supported by aircraft, ships and ground observations. Together they have revolutionized understanding of the planet’s atmosphere, the oceans, the climate and weather. The Obama administration emphasized Earth studies, but the Trump administration has sought to eliminate future Earth missions. This visualization shows the NASA fleet in 2017, from low Earth orbit all the way out to the DSCOVR satellite taking in the million-mile view. (Goddard Space Flight Center/Matthew R. Radclif)

Four of the five Earth science programs the administration sought to cancel are specifically named for funding in the omnibus bill — the Plankton, Aerosol, Cloud, and ocean Ecosystem (PACE) mission, the CLARREO Pathfinder and Orbiting Carbon Observatory 3 instruments and the Earth observation instruments on the Deep Space Climate Observatory spacecraft. A fifth program was already cancelled by NASA earlier this year for technical reasons.

In all, the Science Mission Directorate would receive $6,221 million, an increase of $456  million.  Language in the bill explicitly “reiterates the importance of the decadal survey process and rejects the cancellation of scientific priorities.”

While all this is promising and hopeful, it may well be a short-term reprieve — as reported in that earlier column.

A two-year budget deal reached earlier this year raised spending caps substantially for both defense and non-defense programs, freeing up additional funding that may or may not be available in future years. The 2019 budget needs to be passed in six months, and funds could easily be stripped out then or in subsequent years.

But most important, the administration’s plans to focus on sending astronauts to the moon and establish a colony there could and almost certainly would, in time, eat up large portions of the space science budget.

Under the omnibus bill, NASA would receive $4.79 billion for space exploration efforts, up $466 million over 2017 funding levels.  This includes $2.15 million for the heavy-lift Space Launch System and $1.35 for the Orion space capsule.

The bill also provides $350 million to build a second mobile launch platform at the Kennedy Space Center. NASA considered, but did not request, funding in its 2019 proposal for a second platform.  If built, it could substantially shorten the gap between the first and second launches of SLS by eliminating the delays that would inevitably come at the launch site as it is modified to handle subsequent larger rockets.

Illustration of the Space Launch System as it will appear on the launch pad. In development for almost decade, it is now scheduled for a maiden launch in 2019. (NASA)

In some of its funding, the omnibus bill seems almost too good to be true.

The planetary science program, for instance, received $300 million more than last year.  The $2.2 billion total includes $595 million for work on the Europa Clipper mission and for a follow-on lander — a scientifically exciting aspect of the Europa program, but one that had earlier been cancelled.

The bill also keeps earlier plans to use the SLS to launch Europa Clipper by 2022 and the lander by 2024. An SLS launch would halve the number of years it would take to get the spacecraft to Europa, a moon of Jupiter.

But NASA’s assessment of the SLS program make it highly unlikely that the rockets will be ready for those launches, and there are competing plans to use the second SLS launch to send humans into orbit.

As a kind of added treat, the omnibus bill also provides $23 million for a proposed helicopter NASA has under consideration for the the Mars 2020 rover mission.

The Trump administration has shown great interest in manned missions and little interest in space science and especially Earth science.

Clearly, many members of Congress have very different views, informed no doubt by a highly mobilized space science community.  And for now, at least, they appear to have carried the day.

 

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The Northern Lights (Part Two)

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Northern Lights at a latitude of about 70 degrees north, well within the Arctic Circle. These photos were taken about 30 miles from the town of Alta. (Lisa Braithwaite)

In my recent column about The Northern Lights, the Magnetic Field and Life,  I explored the science and the beauty of our planet’s aurora borealis, one of the great natural phenomenon we are most fortunate to see in the far North (and much less frequently in the not-quite-so-far North.)

I learned the hard way that an IPhone camera was really not up to the job;  indeed, the battery froze soon after leaving my pocket in the 10 degrees F cold.  So the column had few images from where I actually was — about a half hour outside of the Arctic Circle town of Alta.

But here now are some images taken by a generous visitor to the same faraway lodge, who was present the same time as myself.

Her name is Lisa Braithwaite and she is an avid amateur photographer and marketing manager for two popular sites in the English Lake District.  This was her first hunting trip for the Northern Lights, and she got lucky.  Even in the far northern Norway winter the lights come and go unpredictably — though you can increase your chances if you show up during a time when the sun is actively sending out solar flares.

She came with a Panasonic Lumix DMC-G5 camera and did a lot of research beforehand to increase her chances of capturing the drama should the lights appear.  Her ISOs ranged from 1,600 to 64,000, and her shutter speed from 5 to 15 seconds.  The aperture setting was 3.5.

In addition to showing some of her work, further on I describe a new NASA-led and international program, based in Norway, to study the still incompletely understood dynamics of what happens when very high energy particles from solar flares meet Earth’s atmosphere.

Partnering with the Japanese Aerospace Exploration Agency (JAXA,) the University of Oslo an other American universities, the two year project will send eleven rockets filled with instruments into the ionosphere to study phenomenon such as the auroral winds and the turbulence that can cause so much trouble to communications networks.

But first, here are some morre of Braithwaite’s images, most taken over a one hour period on a single night.

Arcs are a common feature of the lights, sometimes reaching across the sky. They form and then break up into smaller patches. (Lisa Braithwaite.)

 

The line of the Arctic Circle line can be seen a little more than half-way up the map. The Circle is the most northerly of the five major circles of latitude as shown on maps of Earth. At about 65 degrees North, it marks the northernmost point at which the noon sun is just visible on the December solstice and the southernmost point at which the midnight sun is just visible on the June solstice. (Stepmap.com)

Vast curtains of light are a common feature, often on the horizon but on good nights high up into the sky.  The lights can sometimes shimmer and dance, and can feature what appear to be vast spotlights.

 

The lights are often green — the result of interactions between high energy solar flares and oxygen.  If the lights are blue, then nitrogen is in play.  (Lisa Braithwaite)

 

At certain points in the night, large parts of the sky were lit up — leaving us turning and craning our heads to see what might be happening in different regions. (Lisa Braithwaite)

 

The light shows often start and end with green horizons.  (Lisa Braithwaite)

While the grandeur of the lights attracts an ever increasing number of adventurous lovers of natural beauty, NASA is also busy in Norway studying the forces that cause the Aurora Borealis — both for the pure science and to better understand the “space weather” that can effect astronauts in low Earth orbit as well as GPS and other communication signals.

The agency has partnered with Norwegian and Japanese colleagues, and other American scientists, in an effort to generally better understand the Earth’s polar cusp — where the planet’s magnetic field lines bend down into the atmosphere and allow particles from space to intermingle with those of Earthly origin.

Solar flares consist of electrically charged particles. They are attracted by the concentrated magnetic fields in the ionosphere around the Earth’s polar regions. This is the reason why the glorious light shows can be observed pretty much exclusively in the far north or the far south.

The two-year project will send eight rockets into space from Norway as part of collaboration of scientists known as The Grand Challenge Initiative – Cusp.

The first mission, the Auroral Zone Upwelling Rocket Experiment or AZURE, is scheduled to launch this month.  The rocket will take off from Norway’s Andøya Space Center, on an island off the far northwest coast of Norway, about 100 miles southwest of where I was near the town of Alta.

As a NASA release of March 1 described it, AZURE’s instruments will measure the atmospheric density and temperature of the polar atmosphere, and will deploy visible tracers — trimethyl aluminum (TMA) and a barium/strontium mixture, which ionize when exposed to sunlight.

Personnel from NASA’s Wallops Flight Facility in Virginia conduct payload tests for the AZURE mission at the Andøya Space Center in Norway. (NASA’s Wallops Flight Facility)

“These mixtures create colorful clouds that allow researchers to track the flow of neutral and charged particles, respectively,” the release reads. “The tracers will be released at altitudes 71 to 155 miles high and pose no hazard to residents in the region.

“By tracking the movement of these colorful clouds via ground-based photography and triangulating their moment-by-moment position in three dimensions, AZURE will provide valuable data on the vertical and horizontal flow of particles in two key regions of the ionosphere over a range of different altitudes.

“Such measurements are critical if we are to truly understand the effects of the mysterious yet beautiful aurora. The results will be key to a better understanding of the effects of auroral forcing on the atmosphere, including how and where the auroral energy is deposited.”

AZURE will focus specifically on measuring the vertical winds in these polar regions, which create a tumultuous particle soup that re-distributes the energy, momentum and chemical constituents of the atmosphere.

AZURE will study the ionosphere, the electrically charged layer of the atmosphere that acts as Earth’s interface to space, focusing specifically on the E and F regions. The E region — so-named by early radio pioneers who discovered that the region was electrically charge, and so could reflect radio waves — lies between 56 to 93 miles above Earth’s surface. The F region resides just above it, between 93 to 310 miles altitude.

The E and F regions contain free electrons that have been ejected from their atoms by the energizing input of the Sun’s rays, a process called photoionization. After nightfall, without the energizing input of the Sun to keep them separated, electrons recombine with the positively charged ions they left behind, lowering the regions’ overall electron density. The daily cycle of ionization and recombination makes the E and F regions especially turbulent and complex.

Aurora as seen from Talkeetna, Alaska, on Nov. 3, 2015. (Copyright Dora Miller)

It has been known for a century that solar flares create the fantastic displays of the Northern and Southern lights.  More recently, it has also become well known that solar flares cause problems for both satellites and navigation systems.

Despite decades of study, scientists still lack the basic knowledge required for predicting when such problems will occur. Once they understand this, it should be possible to make good space weather forecasts just like we do with our weather forecasts on Earth.

When solar storms rain down on the Earth, they cause turbulence in the ionosphere.  This turbulence is one of the major unsolved problems of classical physics and physicists are hoping that the rockets will lead to a far better understanding of the phenomenon.

“Without such an understanding of turbulence it is impossible to make the calculations needed for being able to predict severe space weather events,” said Joran Moen of the University of Oslo, and one of the project leaders. He spoke with the University of Oslo research magazine “Apollon.”

The rockets of The Grand Challenge Initiative – Cusp  mission will launch over the next two years from the Andøya and Svalbard rocket ranges in Norway. Nine of the rockets are from NASA, one from JAXA and one building built the at the University of Norway.

One particular “sounding” will be made with the launch of four rockets at once, an unusual and complex procedure.

Those involved say this will be among the most ambitious attempts ever using rockets for research purposes.

“We will try to launch four of the rockets at the same time. This has never been done before. It is a historic venture,” said Moen.

Yoshifumi Saito of JAXA further explained that “the four parallel rockets are important for us.  By using them we can obtain much better scientific results than would have been the case if we had just launched one rocket at a time.”

Important and compelling science.  And think of how many times the scientists will be able to experience the glories of the Northern Lights show.

 

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Has America Really Lost It’s “Lead in Space?”

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Vice President Mike Pence addresses NASA employees, Thursday, July 6, 2017, at the Vehicle Assembly Building at NASA’s Kennedy Space Center (KSC) in Cape Canaveral, Florida. The Vice President spoke following a tour that highlighted the public-private partnerships at KSC, as both NASA and commercial companies prepare to launch American astronauts in the years ahead.  Pence spoke at length about human space exploration, but very little about NASA space science. (NASA/Aubrey Gemignani)

I was moved to weigh in after reading Vice President Mike Pence’s comments last week down at the Kennedy Space Center — a speech that seemed to minimize NASA’s performance in recent years (decades?) and to propose a return to a kind of Manifest Destiny way of thinking in space.

The speech did not appear to bode well for space science, which has dominated NASA news with many years of exploration into the history and working of the cosmos and solar system, the still little-understood domain of exoplanets, the search for life beyond Earth.

Instead, the speech was very much about human space exploration, with an emphasis on “boots on the ground,” national security, and setting up colonies.

“We will beat back any disadvantage that our lack of attention has placed and America will once again lead in space,” Pence said.

“We will return our nation to the moon, we will go to Mars, and we will still go further to places that our children’s children can only imagine. We will maintain a constant presence in low-Earth orbit, and we’ll develop policies that will carry human space exploration across our solar system and ultimately into the vast expanses. As the president has said, ‘Space is,’ in his words, ‘the next great American frontier.’ And like the pioneers that came before us, we will settle that frontier with American leadership, American courage and American ingenuity.”  (Transcript here.)

Eugene Cernan of Apollo 17, the last team to land on the moon, almost 45 years ago.  (NASA)

That a new president will have a different kind of vision for NASA than his predecessors is hardly surprising.  NASA may play little or no role in a presidential election, but the agency is a kind of treasure trove of high profile possibilities for any incoming administration.

That the Trump administration wants to emphasize human space exploration is also no surprise.  Other than flying up and back to construct and use the International Space Station, and then out to the Hubble Space Telescope for repairs, American astronauts have not been in space since the last Apollo mission in 1972.  It should be said, however, that no other nation has sent astronauts beyond low Earth orbit, either, since then.

Where I found the speech off-base was to talk down the many extraordinary discoveries in recent decades about our planet, the solar system, the galaxy and beyond made during NASA missions and made possible by cutting-edge NASA technology and innovations.

In fact, many scientists, members of Congress and NASA followers would enthusiastically agree that the last few decades have been an absolute Golden Age in space discovery — all of it done without humans in space (except for those Hubble repairs.)

To argue for a more muscular human space program does not have to come with a diminishing of the enormous space science advances of these more recent years;  missions and discoveries that brought to Americans and the world spectacular images and understandings of Mars, of Jupiter and Saturn and their potentially habitable moons, of Pluto, of hot Jupiters, super-Earths and exoplanet habitable zones, and of deep, deep space and time made more comprehensible because of NASA grand observatories.

To say that the United States has given up its “lead in space,” it seems to me, requires a worrisome dismissal of all this and much more.

Selfie of Curiosity rover on sedimentary rock deposited by water in Gale Crater on Mars. (NASA)

Let’s start on Mars.  For the past 20 years, NASA has had one or more rovers exploring the planet.   In all, the agency has successfully landed seven vehicles on the planet — which is the sum total of human machinery that has ever arrived in operational shape on the surface (unless you count the Soviet Mars 3 capsule which landed in 1971 and sent back information for 14 seconds before going silent.)

One of the two rovers now on Mars — Curiosity — has established once and for all time that Mars was entirely habitable in its early life.  It has drilled into the planet numerous times and has tested the samples for essential-for-life carbon organic compounds (which it found.)  It also has detected clear evidence of long-ago and long-standing lakes and rivers.  And it measured radiation levels at the surface over years to help determine how humans might one day survive there.

I think it’s fair to say that Curiosity has advanced an understanding of the history and current realities of Mars more than any other mission, and perhaps more than all the others combined.

Equally important, the almost two-thousand pound rover was delivered to the surface via a new landing technique called the “sky crane.”  If your goal is to some day land a human on Mars, then learning how to deliver larger and larger payloads is essential because a capsule for astronauts would weigh something like 80,000 pounds.

The European Space Agency, as well as the Russians and Chinese, have tried to send landers to Mars in recent years, but with no success.

And as for Curiosity, it has been exploring Mars now for almost five years — well past its nominal mission lifetime.

This Cassini image of Saturn is the of 21 frames across 7 footprints, filtered in groups of red, green, and blue. The sequence was captured by Cassini over the course of 90-plus minutes on the morning of October 28th. Like many premier images from space, an individual — here Ian Regan — used the public access information and images provided by NASA of all its missions to produce the mosaic. (NASA/JPL-Caltech/Space Science Institute/Ian Regan)

NASA missions to Saturn and Jupiter have sent back images that are startling in their beauty and overflowing in their science.  And they have found unexpected features that could some day lead to a discovery of extraterrestrial life in our solar system.

The most surprising discovery was at Saturn’s moon Enceladus, which turns out to be spewing water vapor into space from its south pole region.  This water contains, among other important compounds, those organic building blocks of life, as well as evidence that the plumes are generated by hydrothermal heating of the ocean under the surface of the moon.

In other words, there is a global ocean on Enceladus and at the bottom of it water and hot rock are in contact and are reacting in a way that, on Earth at least, would provide an environment suitable for life.  And then the moon is spitting out the water to make it quite possible to study that water vapor and whatever might be in it.

If the last decades are a guide, up-close study of these icy moons is a challenge and opportunity that the United States alone — sometimes in collaboration with European partners — has shown the ability and appetite to embrace make happen.

NASA’s Cassini spacecraft completed its deepest-ever dive through the icy plume of Enceladus on Oct. 28, 2015. (NASA/JPL-Caltech)

The plumes were investigated and even traversed by the Cassini spacecraft, which is a joint NASA-ESA mission.  The primary ESA contribution was the Huygens probe that descended to Titan in 2005.   To people in the space science community, these kind of collaborations — generally with European space agencies — allow for more complex missions and good international relations.

Plumes of water vapor have also been tentatively discovered identified on Jupiter’s moon, Europa.  The data for the discovery came mostly from the Hubble Space Telescope, and is already a part of the previously approved NASA future.  The Europa Clipper is scheduled to launch in the 2020s, to orbit the moon and intensively examine the solar system world believed most likely to contain life.

The plumes would be coming from another large global ocean under a thick shell of ice, a body of water understood to be much older and much bigger than that of Enceladus. Clearly, having some of that H2O available for exploration without going through the thick ice shell would be an enormous obstacle eraser.

A follow-up Europa lander mission has been studied and got favorable reviews from a NASA panel, but was not funded by the Trump Administration.  Several follow-up Enceladus life-detection missions are currently under review.

This very high resolution mosaic image of the Pillars of Creation was taken by the Hubble Space Telescope in 2014 and is a reprise of the iconic image first taken in 1995. The pillars are part of a nebula some 6,500-7000 light-years from Earth, and are immense clouds of gas and dust where stars are born. (NASA)

I think one could make a strong case that the Hubble Space Telescope has been the most transformative, productive and admired piece of space technology ever made.

For more than two decades now it has been the workhorse of the astrophysics, cosmology and exoplanet communities, and has arguably produced more world-class stunning images than Picasso.  In terms of exploring the cosmos and illustrating some of what’s out there, it has no competition.

There is little point to describing its specific accomplishments in terms of discovery because they are so many.  Suffice it to say that a collection of published science papers using Hubble data would be very, very thick.

And because of past NASA, White House and congressional commitment to space science, the over-budget and long behind-schedule James Webb Space Telescope is now on target to launch late next year.  The Webb will potentially be as revelatory as the Hubble, or even more so in terms of understanding the early era of the universe, the nature and origin of ubiquitous dark matter, and the composition of exoplanets.

Preliminary planning for the great observatory for the 2030s is underway now, and nobody knows whether funding for something as ambitious will be available.

The era of directly imaging exoplanets has only just begun, but the science and viewing pleasures to come are appealingly apparent. This evocative movie of four planets more massive than Jupiter orbiting the young star HR 8799 is a composite of sorts, including images taken over seven years at the W.M. Keck observatory in Hawaii. (Jason Wang/University of California, Berkeley and Christian Marois, National Research Council of Canada’s Herzberg Institute of Astrophysics. )

Many of the early exoplanet discoveries were made by astrophysicists at ground-based observatories, and were made by both American, European and Canadian scientists.  NASA’s Spitzer Space Telescope and others played a kind of supporting role for the agency, but that all changed with the launch of NASA’s Kepler Space Telescope.

From 2009 to today, the Kepler has identified more than 4,000 exoplanet candidates with more than 2,400 confirmed planets, many of which are rocky like Earth.  Of roughly 50 near-Earth size habitable zone candidates detected by Kepler, more than 30 have been verified.

The census provided by Kepler, which looked fixedly at only one small part of the deep sky for four years until mechanical, led to the consensus conclusion that the Milky Way alone is home to billions of planets and that many of them are rocky and in the habitable zone of their host stars.

In other words, Kepler made enormous progress in defining the population of exoplanets likely to exist out there — a wild menagerie of objects  very different from what might have been expected, and in systems very different as well.

Two additional NASA observatories designed to detect and study exoplanets are scheduled to launch in the next decade.

A NASA rendering of a possible moon colony, along the lines of the International Space Station. It was proposed in 2006 by President George W. Bush.) NASA

Given the number of references to our moon in Pence’s Kennedy Space Station speech — and the enormous costs of the also often referenced humans-to-Mars idea — my bet is that moon landings and perhaps a “colony” will be the Administration’s human space exploration project of choice.

I say this because it is achievable, with NASA rockets and capsules under construction and the fast-growing capabilities of commercial space competitors.  We have, after all, proven that astronauts can land and survive on the moon, and a return there would be much less expensive than sending a human to Mars and back.  (I’m also skeptical that such a trip to Mars will be technically feasible any time in the foreseeable future, though I know that others strongly disagree.)

As readers of Many Worlds may remember, I’m a fan of a human spaceflight project championed by former astronaut and head of NASA’s Science Directorate John Grunsfeld to assemble a huge observatory in space designed to seriously look for life around distant stars.  This plan is innovative, would give NASA and astronauts an opportunity learn how to live and work in deep space, and would provide another science gem.  It would indeed show American space leadership.

But here is why I think a moon colony is going to be the choice:  Russia, China and the Europeans have all announced tentative plans to build moon colonies in the next decade or two.  So for primarily strategic, competitive and national security reasons, it seems likely that this kind of “new frontier” is what the administration has in mind.

After all, Pence also said in his speech at the KSC that “Under President Donald Trump, American security will be as dominant in the heavens as we are here on Earth.”  (An apparent reference to both NASA and the military space program, which is significantly better funded than NASA.)

Setting up an American moon colony would be very costly in dollars, time and focus, but it’s not necessarily a bad thing.  Given that a pie can be sliced just so many ways, however, it’s pretty clear that a major moon colony project would end up taking a significant amount of funding away from space science missions.

Returning to the moon and even setting up a colony is not, however, an example of American leadership.  Rather, it would constitute a decision for the United States and NASA to, in effect, follow the pack.

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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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