Another (methane) puzzle piece falls into place

This post is, effectively, a continuation of a previous discussion about methane but with an important added piece of the puzzle included: a solution which includes the constraint levied by the Trace Gas Orbiter. Since it's very hard to draw/visualize methane, this post like so many others, has a wonderful picture of the spacecraft that made the measurements - the curiosity rover, pictured above, with a jigsaw puzzle mask for effect! (original masking image CC 2.0 description and license here)

You might think it a bit strange, publishing two papers back to back 4 months apart on the same topic. After all, my last paper talking about methane on Mars only came out in Nature Geoscience in March and was fully published in May. And now, here my co-authors and I am again with a paper in Geophysical Research Letters talking about explanations for the seasonal cycle. Part of the story has to do with differences in time to publication for the two journals. But the bigger story is that this past year has seen a surprisingly quick evolution in our understanding of this trace gas.

The Solar System: a proving ground for interstellar spacecraft

The above picture illustrates a small spacecraft attached to a solar sail, as depicted by By Kevin Gill from Nashua, NH, United States ( Solar Sail, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=42599221 ). Such Solar/Laser sails are the only technology currently proposed for travel to other solar systems in a reasonable amount of time and, as of yet, not practicable except on paper.  Of course, such "starchips," as they are known, would have to be much smaller than the spacecraft pictured above and would travel in larger numbers ("think smaller, think way more legs"). Hugh Podmore and I wondered what the advent of such a technology might mean for planetary science within our own solar system.

Late last year I finally published a fun paper that myself and Hugh Podmore, one of Prof. Regina Lee's PhD students, wrote up in the summer of 2017. It was a pure flight of intellectual fancy for which we sought and received no funding. What was the subject, you may ask: what else could you do with the starchip spacecraft that the breakthrough star-shot initiative is working towards in order to advance our knowledge of our own solar system? While some of the possibilities had been detailed in the original paper by Prof. Lubin, his ideas for how the interstellar laser array could be used to explore the solar system go big whereas we wanted to know what could be bought in terms of time and cost for going small instead.

It seems that there is a quite a bit that one could do. But what surprised us most was how quickly such spacecraft could be of use to planetary science, perhaps as early as the mid 2020s, allowing early starchip prototypes to be tested out while doing valuable science.  They could also be a democratizing force by allowing smaller space actors (such as Canada) to participate in a way that hadn't been previously imagined, due to the  relatively low cost of laser propulsion once the pushing station is set up. Finally, if you stop to think about it, there really are a lot of great uses for small, fast spacecraft. In our solar system there are things that are fiendishly difficult to do with a discovery-class NASA mission or that simply don't justify that classification's $500 million price tag. I'll get into all these interesting possibilities just below the cut.

A small step towards solving the mystery of martian methane

What does the seasonal cycle detected in Curiosity's record of methane concentration mean? Last week, I published a paper in Nature Geoscience with eight of my colleagues that attempts to answer that question. In the spirit of what I put together for my Nature penitentes paper back in January of 2017, I've decided to summarize the work here. This work was three years in the making, but the story of how it came to pass is much less exciting than with the penitentes - simply a combination of hard work and tenacity by my colleagues and I, like all good science. You can't tell the story of my paper without knowing the story of Martian Methane. So I've put together a primer. For those of you who have been following this closely, skip down to Chapter 2.

Chapter 1: The methane story so far

Whither methane, Mars' most mysterious gas? Since it was first discovered telescopically by Michael Mumma's group in 2003, methane has captivated our interest in the red planet. And with good reason: on the Earth, most methane is produced by biology.

Could the same be true on Mars? That's a complicated question to answer. For starters, there's very little of the stuff to go around. On Earth, methane makes up just under 2 parts per million (ppmv*) of the atmosphere, whereas on Mars the values recorded by different groups place the value at between 0.5 and 50 parts per billion (ppbv*) of the much thinner atmosphere. That allows other processes to have a significant effect. For instance, serpentinization of rocks at depth can also produce enough methane to explain these values, as can seeps of methane stored during Mars' early history either as organic carbon compounds or in methane clathrates. Heck, there's even enough accretion of organic matter via Interplanetary Dust Particles each year to produce 11 ppbv if it all gets converted into methane! None of this even considers processes that remove methane from the atmosphere.

An Updated Model for Methane

The gorgeous view from the Utah Valley Convention Center in Provo. Today I'm talking about what I'm not presenting here (a project conceived, executed, written up, submitted, reviewed and accepted all after the deadline for DPS abstracts!)

Greetings from the 49th annual meeting of the American Astronomical Society's Division for Planetary Sciences! While a bit on the colder side, it's a gloriously sunny day here in Provo, Utah.
But I'm not here to talk about the conference. I've already submitted my talk and picked up my poster, so I've got a few minutes before the reception starts to catch up on my writing a little.

Instead, I wanted to spend some digital ink on my 50th paper (18th 1st author paper) which just came out in-press at Planetary and Space Science. While that's a milestone worth some commentary, I'd like to focus in this post on the Science itself. This particular paper is a novel one for me in that it is an update of a previous model that I had created back in 2012. In fact, a perceptive reader will notice some parallels between this paper and that of Moores and Schuerger (2012). Those are intentional. Indeed, it was our express intention to re-examine our earlier results in light of just how far research on martian methane has come over the past five years.

A Week Amongst the Alps

Combining two facets of my work - an animation of the Siding Spring Comet as seen from MSL in October of 2014 (It's the fuzzy thing which translates across the frame, keeping with the images). Recently, I had the opportunity to talk about the cometary dust that you can see here, rather than the dust in the martian atmosphere - my usual topic of study.

I've been to conferences all over the US, Canada and Western Europe. But never before have I attended an invitation-only conference. I've now had this honour, having just returned from the International Space Science Institute's Cosmic Dust Workshop, which was held in Bern, Switzerland over the past week. I was invited Andrew Schuerger, a convenor, friend and frequent collaborator of mine. Never having done this kind of conference before, I was unsure of what to expect. But I knew that regardless of how things went, that I would learn something new. Plus, Switzerland is rather pretty this time of year and the weather was nice.

Onwards and Outwards

 

Above: Steven Oleson's concept of a Titan submersible combines two of my favorite ideas for future space exploration in our solar system. Below, the polar layered terrain of Mars as revealed by HiRise is a record of past climate just waiting to be read. The story it tells has significance not just for Mars, but perhaps for the Earth as well.

Spurred on by Slate.com reporter Matthew Francis, I have recently got to thinking about where in the solar system I would most like to send a space mission if budget were no object. My comments with Matthew made it into an article in Slate which was also picked up by the National Post here in Canada. But there's only so much you can say in a newspaper or magazine article. 

Instead, exploring this topic this seems like excellent material for this space, and you can find my own personal top four below the cut. By the way, I can't forget adding a thank-you to JPL Engineer Keri Bean, currently working with the Dawn mission (though she has shown an affinity for Mars in the past), who recommended me to Matthew in the first place!

State of the Blog (2011-2012)

Yes, folks it's time again for the annual year-in-review here on HTWT. I'll link to last year's post so that when I come back here next year I can follow the digital trail of breadcrumbs into my own past. Without fear of reversal, I can say that this past year was truly an exceptional one on just about every level. Right now things are really looking up for the future and I hope that my current streak continues.

A Puzzle of Winds

The composition "Seasonal Winds" by my favourite artist and photographer Greg Martin imagines what 400 km/h would look like ripping down Chasma Borealis on Mars. It's too bad such atmospheric phenomena don't exist since they make for such great art and literature. However, the story of how this misconception has propagated itself is an interesting study in the history of planetary science. Go to http://www.experiencetheplanets.com/ to download a high resolution version of the above image.

This spring I set myself a puzzle to solve. As an atmospheric scientist working on Mars, you get used to hearing from other disciplines about the tremendous winds that this planet has to offer. "They happen twice each year as the winter hemisphere moves from North to South and back again - all that CO2 sublimates and rushes towards the other pole." If not this story, then it is tales of some kind of a self-sustaining instability in the global dust storms which occur periodically. However it happens, this tremendous wind has been invoked to explain all manner of features on the surface of Mars.

By the mid 1990s, the existence of such winds was common knowledge extending even into the Science Fiction world. Two highly awarded novels - Greg Bear's "Moving Mars"and Kim Stanley Robinson's "Red Mars" - both have major plot points where such winds are important. In the former, a large pressure wave kicked up by a dust storm and featuring supersonic winds disturbs Casseia Majumdar and her new husband on their honeymoon and, temporarily, provides the environmental conditions necessary for reviving past martian life. In "Red Mars" colonists Nadia and and Arkady are nearly killed when their dirigible is thrown off course in an intense dust storm. When they go outside to repair damage, they can barely stand up, even though the pressure is only 12 milibars (hence the winds must be enormous!) Both of these occurrences are significant because they postulate Mars as it exists today, not some distant terraformed future.

That would be all well and good except these winds don't actually exist! The highest windspeed recorded by our landed missions, our best determinant of ground level windspeed on Mars, was 16 m/s (~58 km/h or 36 mph) for the Phoenix Lander. You might say: "that's all well and good, but Phoenix only lasted 152 sols during northern summer, a fairly quiescent time." You would be right, however, the much longer 2245-sol (~7 Earth Year/3.5 Martian Year) Viking Lander missions saw the entire seasonal cycle several times over and were operating during the two "great dust storms of 1977." Their record shows no windspeed in excess of 19 m/s (68 km/h or 43 mph).

Meet the Team

My UWO MSL Team. From left to right we are Raymond Francis, Emily McCullough and John Moores. David Choi is not shown, but you can take a look at him below.
Photo credit: Mitch Zimmer.

As of last Wednesday I can say that I am a Participating Scientist on the Mars Science Laboratory Mission. That mission launched successfully last Saturday and we're now on our way to Mars. In the meantime, we have work to do. There are models to test, training for operations to complete and data reducing software to write. I won't pretend that I can get this all done by myself in the next eight months. Luckily, I don't have to. I've got a great team behind me and I wanted to help to shine a spotlight on them and what we hope to accomplish together - they deserve it!

Words just cannot describe this...

So I won't even try. 

Mars Science Laboratory is shown here in this picture I took at the parking lot of OFB-1 (our shelter in case of a launch failure), near the VAB at Kennedy Space Centre and 6 miles from pad 41 at 10:02:09.2 AM on Saturday, November 26, 2011, 9 seconds after the main engines of the Atlas-V started it on its way to Mars. Best of luck, little rover - our thoughts, prayers and hopes go with you.

Getting Ready for the Cape

MSL Arrives at Launch Complex 41 inside its 5m fairing just before dawn on November 3. In the days ahead, this fairing will be mounted atop an Atlas-V 541 EELV for a launch to Mars no earlier than November 25. 

After some consideration, I've decided to bite the bullet, take a chance and head on down to Cape Canaveral next week to help see off Mars Science Lab (MSL). Better known as the Curiosity Rover, MSL is an exciting mission to Mars that will take a close-up look at the km-thick layered deposits inside Gale Crater. It's an exciting place to try for and the rover team is looking forward to a successful launch, landing and the scientific results that will be returned. Unfortunately, I was unable to attend the spectacular night launch of Phoenix in 2008. So this will be my first launch, assuming that delays don't push the launch back until after I need to fly home.  While I have some idea what to expect from video and images, I have no idea what the experience will be like in person.

Dr. Hojatollah Vali's CATP Seminar

 Astrobiology's favourite martian meteorite, Alan Hills 84001 is shown alongside a Magnetosome, a bacteria that fixes iron within its body to form magnetite and gives itself a free ride (or orientation) courtesy of the Earth's magnetic field. Could the tiny magnetite crystals serve as biomarkers long after the host is gone? And what is the origin of these kinds of features in ALH84001?

Recently, we kicked off the CATP  seminar series for the 2011-2012 season! The first talk of the year comes from McGill University's Hojatollah Vali. Dr. Vali's work is mainly concerned with the ability of iron-fixing bacteria to serve as biomarkers long after the bacteria have long since passed away. It's just one way that we can answer the question of how to detect past biological activity in the absence of well-developed morphologically distinct fossils.

Another conference and more bad news looming

ESA's TGO - Last ditch negotiations are expected Monday in South Africa at the International Astronautical Congress to see if this mission can be saved.

As I was crossing the Atlantic, Universe Today was reporting some details about the negotiations between ESA and NASA with respect to the ESA Exo-Mars program. From the sound of the article, barring some last ditch maneuvering at this week's IAC meeting in South Africa, Trace Gas Orbiter could be nearing the end of the road.

Getting Ready for DPS 2011

My two posters for DPS 2011. On the left is a description of the ILSR Analogue Mission Control Architecture, on the right I discuss some suggested atmospheric measurements for MSL and argue for pre-processing on-board landed spacecraft in order to improve the temporal coverage of this dataset. You can get a preview of the Analogue poster here and the Atmospheric/MSL poster here.

It's almost time for the 2011 edition of the AAS's (American Astronomical Society's) Division for Planetary Sciences Conference, better know to us in Planetary Science as DPS. Next week, those of us interested in planets will descend upon the conference centre in Nantes, France. As happens every five years or so, this conference is being held in concert with our European counterparts, the EPSC (The European Planetary Science Congress) who have shared the organizing duties. This has meant, among other things, an extended abstract process which is reminiscent of LPSC's famous 2-page behemoths. Yes, these abstracts have abstracts! But the end result of that extra work is that we all have a better idea of what will be presented by our colleagues.

Springtime for Mars

It's that time of year again! The days are getting longer, the temperature is getting higher and there's a breeze in the air as the dry ice is evaporating away. Layers of terrain, stable for millenia are beginning to collapse in avalanches:

Hi-Rise catches the start of "Avalanche Season" on Mars.

What does JWST mean to Mars?

Some of the best images of Mars obtained using the Hubble Space Telescope. JWST could give us methane maps of the planet that approach this spatial resolution, but what are the costs for planetary science?

For those who thought that PSD's (NASA Planetary Science Directorate) budget woes came to a close along with the debt-ceiling increase, the bad news just keeps rolling in. Let's take a few minutes and analyze what consequences the recent dealings with the James Webb Space Telescope (JWST) will have on our exploration of Mars.