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.

Exploration: an activity suitable for all audiences

The cover of the August edition of CMOS' Bulletin - the middle image hints at a medium-complexity article, an interesting art form which is more complex than a standard outreach article and less complex than a full-on scientific article. Such medium-complexity prose can be a challenge to write, but has particularly valuable potential payoffs.

Even a casual and infrequent visitor to this blog will know that I feel it's important to write for a variety of audiences. Often I'm emphasizing either a professional audience, in speaking about published research that I or my students have led (50 papers now, as of last month!), or a general outreach audience to share the enthusiasm, excitement and wonder of space exploration. If there's not enough evidence of the latter in these pages for you, allow me to direct you across to my lab's blog at york-pvl.blogspot.ca where you can hear from my students!

But there's a third audience for which I don't typically write - the deeply interested layperson or mildly interested expert. Here, I'm talking about folks who don't get a paycheque doing planetary science, but who can tell the difference between New Frontiers and New Horizons.* Combine those with practicing scientists and engineers who might work in sister (and typically terrestrial) fields like Geology, Atmospheric Science or Space Engineering who know the difference between cirrus and cumulus,** penitentes and suncups,*** or framing and push-broom cameras,**** but who are surprised to see the word 'Mars' or 'Pluto' before those familiar terms. Think the readership of Scientific American, or Physics Today here.

State of the Blog (2016-2017)

 

The members of TEPS and our guests at the Université de Montréal in June. This year saw enormous growth in our program, something very satisfying to see as an author of the proposal and as a member of the team!

It's July and that can only mean one thing, here at HTWT: time for the annual State of the Blog update! Unlike last year, I did manage more than zero posts with 8 in all. I also kicked off a new Blog for my lab over at http://york-pvl.blogspot.ca/ which has had 33 posts describing life, research and teaching amongst my students and trainees. The content over at our new location has been rather good and some of the posts have been very popular - in all we've had about 2,600 visitors over the year, not a bad start at all.

The big news over the last year will be no surprise to our regular readers. To my utter shock and amazement I published an article in Nature. If you talked to me a year ago, I would have thought you crazy to suggest that such a thing could happen. But this business is full of surprises. I won't spill much digital ink rehashing the experience (but if you want to rehash, by all means click for my description and background commentary) other than to say that I'm pleased that I can still learn new things about the business of getting science published despite having been doing planetary for 14 years. It was also very nice to be honoured by York University as a Research Leader for 2016 as a result.

Come and Learn the Art of Exploration

The author takes a selfie with the Curiosity Rover at NASA's Jet Propulsion Laboratory, one building over from Curiosity's Mission Control where he worked during the summer of 2012. We hope to give those who attend our event on May 27, 2017 a taste of what running a space mission like Curiosity is really like.

Last year I was fortunate to be successful in my bid to secure an Ontario Ministry of Research and Innovation Early Career Researcher Award. In addition to allowing me to expand the Curiosity (Mars Science Laboratory)-related work that we do in my group, this particular award has a youth outreach component that we're about to roll out for the first time. I think we've put together a really interesting day if you want to get an idea of what it's like to do real planetary exploration. I know that my team and I are really looking forward to sharing our enthusiasm with those students who join us on Saturday, May 27!

Some of you may have navigated to this post in order to get more information on the event, so this will serve as exposition. Over the course of six hours, from 9:30 AM to 3:30 PM, we hope to give you all a little taste of what science-driven mission design is like. The "science-driven" component is important because, where space exploration was at one point focused purely on pushing boundaries (what we call "footprints and flags"), the modern version has an animating purpose in mind, and that purpose is the science that is returned. Think of it as the difference between John Cabot's "Matthew" and Charles Darwin's "Beagle." We will start with how you select a landing site before describing how you go about equipping a robot for the journey and then how that robot is operated on another planet to actually accomplish science goals. In each case, it will be you and your fellow students who make the choices.

A Banner Conference

 

While twitter is going somewhat crazy over Jake's videos, especially the gravity wave one, this one is my favourite, not only for the patterns in the clouds, but also for the shadow cast on the foothills of Mt Sharp. While this development was the most unexpected success of the group at this year's LPSC, it was far from the only event that made this a conference to remember.

I've just returned from 2017's Lunar and Planetary Science Conference (LPSC) held this year, as every year, in the Woodlands, Texas. No matter which way you cut it, this year's conference was a tremendous success for PVL. That's not hyperbole, despite the fact that LPSC holds a special place in my own Planetary Science Education (the 2004 edition was where I realized that I wanted to be a planetary scientist) and it's an excuse to spend a week in 25C+ weather in the middle of March and meet up with old friends from graduate school.

There were a few things we knew coming in would make this year a banner year and a few surprises that heightened the experience.

A surprising, serendipitous turn of events - the making of a Nature Paper

My new favourite planet (don't tell Mars!). This post tells the story of how the Nature penitentes paper came about. A previous post described our findings in plain language. I must apologize in advance, the length really got away from me on this one. But I hope the tale which follows is instructive for other early career folks in the planetary sciences (and other disciplines) who have a flash of inspiration that leads them towards high-impact publishing and who are not already members of science teams.

If you have to blame someone, blame Geoff Languedoc*.

Penitentes on Pluto

Though not posted until after the embargo clears, I'm writing this post over the winter holidays out in Gander, NL. It's plenty cold, snowy and icy, but far too windy and humid for Penitentes to form here! The image above was captured by the Ralph/Multispectral Visual Imaging Camera on the New Horizons Spacecraft in July of 2015. The image shows the Tartarus Dorsa region of Pluto which has been sculpted by the sun into a regular pattern of icy blades.

This post is intended to offer up a few details about my recent article that appeared online in the January 4th edition of Nature. You can navigate to the paper itself using this link and the York and NASA/APL press releases are also linked.  Because Nature articles are very information rich, I was thinking that an unpacking of my recent article might be helpful to some of my readers out there. Note that how this article came to be may be the subject of a separate but related post which I'll post once things calm down a bit. Instead, this post focuses on the content of the paper and you can read more down underneath the cut.

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.

The Summer of Public Speaking

.@ArcticSaxifrage starts off the morning talking about the importance of studying our own solar system @Starfest2016 pic.twitter.com/CKs6zen7KC

— York Observatory (@yorkobservatory) August 6, 2016

I won't deny it, I enjoy giving public talks about my science. Not only is it fun, but it also serves the cause of informing the public about exactly what it is that we do in planetary science and exploration and gives my research funders a good return on their investment. What more could a public servant such as myself want? I try to accomodate all the talks that are requested of me, but the summer is always easier to schedule than are other times of the year, so often you'll stand a better chance of hearing me when the weather is warm.

A Triumphant Return to the Radio

It's good to be back even if no one will be throwing my return a ticker-tape parade, such as the one pictured above for the Apollo 11 lunar astronauts (as photographed by Bill Taub for NASA's human space flight gallery ). With apologies, I just couldn't resist the spaceflight reference!

After a hiatus of nearly 4 years, I have decided to make Astronomy.fm (AFM) a regular part of my life again. Those of you who are avid listeners of YorkUniverse may have detected my dulcet tones twice over the last few months. I was a 'guest' of the show before graduating to 'co-host' last month and tonight I'll be co-hosting again this time with the master himself, Paul Delaney. Over the coming months you can expect more of the same. With luck I'll be able to inject my usual dose of planetary and spacecraft know-how into the discussion. It will be fun and informative! I hope you can join us.

A New Blog: PVL

Earlier this month I welcomed a 3rd member to the arcticsaxifrage blogging family. As some of you may already know from clicking on my profile over on the right, I've got my professional blog right here as well as a second blog where I review science fiction. To that I'm adding one more, but here's the catch - largely I won't be the author!

Instead, york-pvl.blogspot.ca will talk about the work going on in my laboratory, the Planetary Volatiles Lab (PVL) here at York. As I indicate in the introductory post, the forum will be contributed by students and trainees in order to give them experience in writing for a general audience. There's good potential here for benefits all around, I think.

If you are curious what you'll find, there will be posts about our science and engineering (though don't expect us to give away our secrets pre-publication!) as well as posts on process (What is it like to write your first paper; to give your first conference talk?) and on interesting things going on in planetary, from a student perspective (i.e. what a fantastic paper in last month's Science!)

Through this new forum I hope that you will get a taste for what it is that we do, why we do it and how we do it. You'll also get to know a whole new cast of characters. However, it will be a moderated forum in which I have reviewed and lightly edited the content - so don't expect too much drama.

I hope you'll join us, and will cheer on my students, many of whom are writing this kind of content for the first time!