Penitentes: where art thou?

 Hidden in amongst the ice penitentes above is PVL PhD student Giang Nguyen! Original image "Penitentes ice formations at the southern end of the Chajnantor plain in Chile in 2005." credit: ESO, https://www.eso.org/public/images/img_1824/

By Tue Giang Nguyen

A great deal of my research recently has been dealing with atmosphere-surface interactions. In conjunction with my survey for dunes on the Martian polar cap, I’ve also been looking for surface features called penitentes. For the uninitiated, penitentes are ice and snow blade structures common in tropical alpine regions such as the Andes and the Himalayas. Although Darwin thought that these ice blades were sculpted by the wind, later glaciological research proved otherwise.

Penitentes are formed by uneven heating and subsequently sublimation of an icy surface. Imagine a pair of mirrors held together forming a v-shape with their reflective surface pointing up. Now from above, if you shine a laser onto the v-shape mirrors, you will probably see that the light will bounce between the walls sending light towards the bottom of the v. This dynamic of light bouncing off the reflective side walls and concentrating towards the depression is how the ridges and troughs of penitentes take their shape. As the trough receives more heat and sublimate more water, it deepens while the side walls receive less heat and sublimate more slowly.

Searching for Liquid Water on Mars at the Canadian Light Source

 

PVL is branching out in time! Not content to limit ourselves to today's Volatile Reserves on Mars, two members of the group, PDF Paul Godin and PhD Candidate Charissa Campbell headed out to Saskatchewan to examine the ancient atmosphere. In the image above, Paul Godin (York), Tyler Wizenberg (U of T), and Charissa Campbell (York) are pictured in front of the Canadian Light Source.

 by Dr. Paul Godin

A recent paper by Wordsworth et al. (https://doi.org/10.1002/2016GL071766) suggested that the greenhouse effect on ancient Mars could be stronger than previously thought due to a phenomenon called collision induced absorption (CIA). CIA is when molecules in a gas collide with each other and for a brief moment form a two-molecule complex that has its own absorption features. 

Wordsworth’s paper made a computation prediction of what the CIA for the Martian atmosphere would look like, but experimental verification of their prediction is still required. CIA is a weak absorption feature and requires spectroscopy set-ups that have long path-lengths or can handle high pressures to detect it. One method to achieve a long path length is known as a multi-pass White cell; in this set-up mirrors are placed at both ends of the cell and a beam of light is bounced back and forth between them (as shown in Figure 1), allowing for more time for the light to interact with the gas.

When you tweet and the Universe tweets back...

Engagement with the public is an important activity for us here at PVL. Many would think about this largely as a one-way street with scientists preparing materials for public consumption, such as a presentation, a documentary or a book. But it's always a richer experience when you're having a two-way conversation, as Christina describes in this week's Blog post. Sometimes the level of engagement displayed by that response can be surprising! Note that the photo above is a word cloud she made from some of the jobs respondents are currently doing (sizes randomly assigned).

By Dr. Christina L. Smith

 

One of the things I think is important as a scientist is making sure that not only the scientific community knows of your work (and general existance) but also that the wider public is able to engage with you and your research, when appropriate of course. As my previous posts (i.e. poetry in science and the Rover Exploration Challenge) show I particularly enjoy getting involved in public engagement in a variety of formats!

A couple of months ago, I was invited to give a presentation at a “Future Women in STEM” (STEM = Science, Technology, Engineering and Mathematics) day held at York University, talking about my personal experience as a woman in STEM. I realised that, although there were a large number of very interesting presentations and activities on the agenda, mine was the only one revolving around someone’s personal experience in a science field. I’m also very aware that STEM careers are far, far broader than my own personal experience.

Heiligenschein Throughout the Solar System

Greenler's 1980 classic "Rainbows, Haloes and Glories" is a must-read around our lab. I can remember being introduced to the book by my own PhD advisor, Peter Smith way back in 2003. It's still a useful and engaging tome, describing optical effects valid for atmospheres around any planet, and even some bodies without atmospheres! As for the photos above, they are annotated images of the Asteroid Ryugu, as Hyabusa 2 approaches (Images: JAXA), with arrows pointing to the area where Heiligenshein is observed.

by Brittney Cooper

Folks in the planetary community have been buzzing about the ongoing successes of JAXA’s Hayabusa 2 (http://www.hayabusa2.jaxa.jp/en/) over the last couple weeks – and with good reason! Even though it focuses on a solar system body that has no atmosphere (I’m kidding…sort of), it is still an exciting sample-return mission that features some great science, 2 adorable hopping rovers, a lander, and a real-time image downlink. 

When I was scrolling through the down-linked images of Hyabusa 2’s approach of Asteroid Ryugu, a familiar sight caught my attention (and the attention of those who share in my niche appreciation for scattering and optical effects). It wasn’t the spacecraft’s shadow resembling a Canadian flag (though I think we appreciated that as well), but rather, a brilliant heiligenschein.

A Successful Rover Exploration Challenge

In late July, PVL's "Rover Exploration Challenge*" came to the Ontario Science Center. There we shared a little bit of what we do in planetary space exploration with 400 members of the public over two days. Charissa (center of photograph), along with Christina, worked tirelessly to ensure the success of this event and we're already talking about repeating it next year! Look for our DPS abstract in a few weeks time which will describe what we learned from all of you in the course of designing and carrying out this simulation. And on a timely note, congrats to Charissa on the successful defense of her MSc thesis. I have updated her tag in this article accordingly.

By Charissa Campbell

Another day, another successful run of our outreach program for rover operations. With now four completed runs, we can successfully say that we have explored multiple styles of outreach. Our most recent run in late July (see Christina’s blog post: http://york-pvl.blogspot.com/2018/07/rover-exploration-challenge-at-ontario.html) was labelled the Rover Exploration Challenge and was significantly different from previous runs. Located at the Ontario Science Centre, participants were visitors that were free to drop into the program during the start of every iteration or planning day. Multiple planning days were carried out, building off the previous iteration. This allowed multiple measurements to be taken throughout the rover’s traverse path. Both Saturday and Sunday’s runs had the same traverse path, but measurements differed based on the participants planning. 

A Somewhat Spontaneous Science Flash

Lately, Christina has been supporting the European & Pacific Divisions of the PVL with a series of four presentations at the IPM and EPSC conferences in Berlin, Germany and the MSL Science Team Meeting in Pasadena, California. Despite this heavy workload, she was able to take time to put together an entry into the EPSC Science Flash competition. While she didn't walk away with one of the grand prizes, twitter gave her an honourable mention for her engaging presentation! Details below.

by Dr. Christina Smith

At some conferences there are events held that host talks that are a little different to the standard conference-style oral presentation. I recently attended the European Planetary Sciences Congress in Berlin, and at this conference the Europlanet Early Career Network hosted Science Flash 2018.  Science Flash is a competition in which researchers are challenged to present their research in three minutes using only a single slide and doing it in an interesting or unusual way. I discovered the competition on the first day of the conference and decided to give it go less than three days later!

My unusual method for presenting my research was inspired by rhyming stories I used to read as a child. I wanted to present my work as if it were a rhyming children’s story whilst also giving accurate information and background to one of the projects I’ve been working on. So, what follows is what I said word for word and my slide is the picture you see above – and yes I did put a crown on Curiosity!

Water on Mars : A Brief History

RSL animated gif. (Image: NASA/JPL-Caltech/Univ. of Arizona)

Today, our newest MSc at PVL examines a large and well-known problem in planetary science: the water inventory of Mars and how we achieved the state of knowledge we now posses. Grappling with such big picture issues is as important for trainees as is the fine details of their own research.

By Brittney Cooper

The internet was recently abuzz with the latest results from the Mars Advanced Radar for Sub-Surface and Ionosphere Sounding (MARSIS) instrument, as it returned evidence for a sub-surface lake near Mars’ south pole. Of course, that’s not how a lot of us saw it communicated in the news and on social media. It can be incredibly hard to distill intricate and niche scientific findings for the public’s palate, and often you see media outlets striving less to find that balance in favour of simply slapping on a sensationalist title and making sweeping assumptions.

A misleading headline that once again reared its ugly head in many publications was the age-old classic “Water Discovered on Mars!”. The important distinction with this newest discovery is that the water is “liquid”, and while making that distinction may seem like a small oversight, it makes a big difference when considering the geologic, atmospheric, and astro-biological ramifications. Furthermore, water has been known to exist on Mars in both gaseous and solid states  since the 1970s, and in 2015 scientists also claimed to have found salty liquid water on Mars’ surface in the form of recurring slope lineae (see photo above).