Wednesday, October 19, 2022

Completing the Thesis Defence: The Final Boss of a Graduate Degree


This past summer, several of the students in PVL had the opportunity to go through the timeless ritual that all us academics undergo in order to earn our MSc and PhD degrees: the oral defense of our research. I can report that everyone made it through with flying colours! Of course, a defence is also a transition for the student who may be moving from an MSc into a PhD, from a PhD into a Postdoc or from their MSc into the working world, amongst other paths. If you are considering getting a higher degree and want to know what this hurdle looks like, or are starting to think about your own defense, Grace has some helpful insight below. 
(Image above from XKCD Comics: https://xkcd.com/1403/)

 by Grace Bischof

The end of the summer marked a busy time in the Planetary Volatiles Lab. Conor, Giang and I were each nervously preparing for our upcoming thesis defences, where we would learn if we were to pass and obtain our degrees, or fail and be very, very sad. Giang, reaching the end of his PhD in August, defended first, setting the tone for the rest of us by passing! Conor and I followed, defending on September 7th and 8th (apologies to our shared committee members who had to sit in back-to-back defences). Conor and I were also successful in defending our theses, meaning we both obtained our master’s degrees. It was a very exciting end to the summer.

So, what is a thesis defence and why is it so nerve-wracking? In a research-based degree, the findings of the research you complete over several years get written up into a document – at York, this is a thesis for a master’s and a dissertation for a PhD, which is a more robust document than a thesis. This document represents years of hard work, and hopefully, makes an original contribution to the field in which you’re studying. That, in and of itself, is a nerve-wracking process. But before the university can award you your degree for all the painstaking effort you have put into your thesis, they first must test you on the contents in the form of an oral examination.

The oral examination usually begins with a public talk, where your research is presented in a 20 minute to hour long (depending on the degree) presentation. Typically, anyone can join this portion of the defence, and for me, it was fun having my friends and family watch my presentation so they could finally stop asking what it is I actually work on. Once the public talk is over, everyone else leaves the room, so it is just you and your committee. One-by-one, the committee members take turns dissecting your thesis, asking questions, and making suggestions about the contents to facilitate discussion on your work. This process can last several hours, especially for a PhD defence which is more involved. Once the committee has run out of questions to ask, you are kicked out of the room while they deliberate. Sitting outside the room while a small number of people decide the fate on the culmination of your work is horrifying. Then you are finally called back to the room to receive to your verdict…

The good news: the thesis defence is largely a formality. That is, if your research supervisor is doing their job, you will not walk into the thesis defence if you are not going to pass. The purpose of the defence is simply to ensure the student understands their work and the literature in which it is situated. Not knowing the answer to an examiner’s question does not mean you will fail the defence. In fact, the examiners want to see you reason through their questions, applying your knowledge even when you do not have the exact answer. There was one point in my defence when I answered a question completely incorrectly but realized my error once I thought more about it. I told the committee that the answer I gave was incorrect and walked them through my thought process to answer the question correctly. The committee was more interested in seeing my reasoning in getting to the answer than they were worried about the initial mistake I made.

So, now that you know what a thesis defence is, let’s briefly walk through some tips for the defence:

  1. Start preparing early. The amount of time needed to prepare is going to depend on the degree being obtained – i.e., PhD students will likely need to start earlier than master’s student. Three weeks out before my defence I began to seriously prepare. I started by compiling a list of the most important references in my thesis. I read a handful of these a day, highlighting and jotting down notes on important aspects of each paper. At this time, I was also walking through the basics of the field – sure, it might impress your committee to describe in detail all the aspects of radiative transfer in the atmosphere, but that might diminish if you forget Mars is the 4th planet from the sun.

  2. Anticipate questions. About 1.5 weeks from the defence date, I began combing through my thesis line by line. I had a PDF version of my thesis which I used to highlight and make notes in the margins. I wrote down anything that came to mind when reading my work and how the committee might interpret it. Some common questions that are asked in defences are: “How does your work fit into the existing literature”; “Describe your work in a few short questions”; “In what ways can this work be expanded?”; “What limitations did you experience in this work?”. Funnily enough, I prepared for all these questions and did not get asked any of them. However, preparing for them helped me to pick apart my work more carefully, meaning I could answer the questions they did give me.

  3. Try to relax as much as possible. It’s easier said than done. An important tip that I read online before defending my thesis was to make sure that in your state of nervousness, you don’t consistently interrupt the examiners while they are asking questions in an attempt to quickly prove you know the answer. When an examiner is speaking, it’s a perfect time to collect your thoughts and let them talk (it eats up more time this way too!). But, like I said, the defence is largely a formality. If you’ve done the work, then you know your stuff and you will crush it! You are allowed to sit and think about your answer before speaking, drink some water or have a snack, and take a break during the defence if needed. After the first 30 minutes of the defence, the rest breezes by.

Your thesis defence will probably be the only time you will ever have a discussion with people who have ever read the full contents of your thesis. That itself is a pretty cool opportunity, so try to enjoy it as much as you can! Hopefully in four years’ time, when I’m preparing for my PhD defence, I can come back to this blog post and try to take my own advice.  

Sunday, October 16, 2022

PVL in London (Ontario, That Is)

 

This week, new PVL PhD student (formerly PVL MSc student - congrats!) Conor Hayes reflects on the just completed DPS Conference that they attended a few weeks ago. This is the first time that DPS has been in person since Geneva, Switzerland in 2019 and the first time it has ever been held in Canada. I certainly appreciated being able to experience the conference together with my graduate students as a research group without even having to bring my passport!

by Conor Hayes

It has been nearly a year since I last submitted an entry to this blog, detailing my experience at GAC-MAC 2021, my first in-person conference as a grad student. Much has happened since then; I half-pivoted away from the Moon to add a new MSL-based project to my Master's thesis less than nine months before my defence, I wrote and successfully defended said thesis, and now I'm a freshly-minted PhD student here at PVL.

Some things, however, do not change, so I am here once again to talk about our latest conference experience at the 54th Annual Meeting of the Division for Planetary Sciences (DPS). PVL typically puts up a strong showing at DPS because we are all planetary scientists, and this was particularly true this year for two reasons. First, DPS 54 was held in London Ontario, practically down the road (relatively speaking) from us here at York. Second, PVL’s own John Moores was Chair of the Science Organizing Committee, so we couldn’t not represent our group well.

In many ways, DPS was very similar to the two in-person conferences that I was able to attend during my Master’s – GAC-MAC back in November of last year, and the 7th Mars Atmosphere Modelling and Observations conference this summer. The scientific program was divided between oral talks and poster presentations, with a plenary session in the middle of each day. I mostly stuck to the sessions on topics that I’m interested in – the Moon, Mars, and terrestrial planets, though I did attend a few that were more “out there” (at least with reference to my own research) on Europa and other icy moons, as well as sessions on citizen science, education, and public outreach.

Although it followed this familiar pattern, DPS was very much a conference of firsts for me. Because DPS was a hybrid conference this year, each session had two chairs, at least one of whom had to be in-person. One chair would make sure that each speaker stuck to their allotted time and manage questions from in the room, while the other would monitor the session’s Slack channel, where virtual attendees could ask their questions. Due to the continually evolving health situation, there were a number of in-person chairs who had to switch to virtual attendance, meaning that some sessions no longer had an in-person chair. Several members of PVL (including myself) were recruited to take their place. The session that I chaired was titled “Dynamical Dances in Space,” and featured four talks discussing gravitational interactions between various Solar System bodies, the first of which was actually based on a newly-published paper that I had read shortly before the conference. Stepping in as chair at the last minute was a little daunting because I had no idea what to expect, but it ended up being a reasonably non-stressful affair.

Much more stressful was the fact that this was the first time that I had been invited to give an oral presentation at a “major” conference. I’ve given presentations about my research before, but always in much lower-stakes settings, whether that be in PVL group meetings or at smaller conferences run by graduate students (e.g. York’s Physics and Astronomy Graduate Executive conference or the annual Lunar and Small Bodies Graduate Forum). On top of that, I had never presented the preliminary results of my lunar work to a larger group before, so there was a lot that I was worried about. Consequently, I spent a lot of time preparing my presentation and making sure that I stayed as close to the seven minute limit we were given. In the end, the magnitude of my stress was wildly disproportional to the actual event, as my presentation went smoothly and hit the seven minute mark almost exactly. Although I would have happily taken just that as a win, it has also inspired my first official research collaboration with someone outside of PVL, something that I am very excited about.

Now that I’ve had experience with both oral and poster presentations at conferences, I think I can say that I prefer oral presentations over posters. Posters certainly do have their advantages – you present all of your information on a single page and you don’t have to worry about time limits or making sure that you remember what you want to say, as posters often come with a more conversational style of sharing information. However, I’m just not really a fan of the poster experience. During a poster session, you’re sharing a room with many other people presenting their posters at the same time, so there’s a certain element of competing for the attendees’ attention. Some people can also find approaching the presenters one-on-one more intimidating than asking a question at an oral presentation (I certainly do!), which might limit the number of interactions you have. I definitely don’t want to turn people off of poster presentations; they can be a low-stress way to ease your way into the conference experience and/or to present early/preliminary results that are still in progress.

Overall, DPS was probably my favourite conference of the handful that I have attended (either virtually or in-person) over the past two years. I can only hope that the weather in San Antonio will take a break from its usual late-summer Texas heat for DPS next year.

Monday, October 3, 2022

There and Back Again: A MAPLE Tale

 

As we approach the final year of the MAPLE project, it's time to take the instrument out into the field! This past summer, PVL PhD student Charissa Campbell and then-MSc (now PhD) student Grace Bischof took MAPLE out to Argentia, Newfoundland one of the foggiest places on Earth where the Gulf Stream meets the Labrador current. Mother nature didn't disappoint and Charissa and Grace came back with spectacular images and science.

by Charissa Campbell

This summer was quite busy as we were preparing for the deployment of our MAPLE (Mars Atmospheric Panoramic camera and Laser Experiment) instrument to the highly foggy area of Argentia, Newfoundland. There are two main field testing sites for MAPLE which includes a foggy location (large aerosols) and Arctic location (small, Martian-like aerosols). With the Arctic being more Mars-like, MAPLE will travel alone and be controlled remotely to fully mimic spaceflight conditions. However, as a starting point, we decided to travel with MAPLE to the Argentia, NL area to test in foggy conditions.

MAPLE is based on a previous experiment done by the Phoenix lander that took images of the onboard lidar laser to classify ice-water content of aerosols near the surface (https://photojournal.jpl.nasa.gov/catalog/PIA11030). However, the camera could only take an image of a small portion of the sky, limiting the view of the laser. MAPLE is equipped with a panoramic camera to allow the full sky to be captured, which also allows for multiple lasers to be in use at the same time and clouds to be monitored during the day. For Argentia, we equipped MAPLE with 8 different lasers in a variety of wavelengths and power (class) to try to determine if a specific set was better for future measurements. Adding different wavelengths of lasers allows us to also investigate the size of aerosols. To further increase the science output of MAPLE, we will employ techniques used with the Mars Science Laboratory (MSL, Curiosity) to calculate aerosol properties such as optical depth, wind properties and others.  By using knowledge from previous Martian surface missions, we can develop MAPLE in a way to maximize the amount of returnable data in a low-cost way.

Defining a mission as low-cost means trying to find the minimal amount of power, data volume and size needed to acquire your measurements. Since we are in the early stages of the project, we created MAPLE from scratch using a pelican case which held our components. This includes a panoramic camera, 8 lasers and a raspberry pi that is used to control the camera. Several battery packs were used, one for each laser and a separate larger one for just the raspberry pi. As MAPLE gets more automated, the lasers will eventually be controlled by the raspberry pi and power can be more streamlined through just the Pi. The size of MAPLE seemed to work well, and windows had to be installed in the top for the camera and lasers to shine through. I never took construction in school, so I had a lot of late nights with the drill to push through two rectangles for the laser windows. Luckily, we already had a bubble panoramic window so I simply had to construct a properly sized hole for the window. Somehow, I managed to fully construct MAPLE and not injure myself. We also got humidity measuring packs to see how sealed the inside was. Minimal humidity was noted within the case, which is a win considering we were in essentially a cloud most times we were on the field. One concern we did have with keeping MAPLE low-cost was that the images were rather large and I only equipped the raspberry pi with a 32GB SD card. A lot of extra time was spent moving files over to a portable hard drive so we will be looking into upgrading the size of the SD card while also optimizing the size of the images. 


The field site itself was really beautiful and was a bucket list item for me as Newfoundland was the last province for me to visit in Canada. Interestingly enough, there were no rental cars available on the whole island for the 2 week we were wanting to travel. However, with the coming end of the foggy season we didn’t want to miss the opportunity to make observations. I love taking different methods of transportation and stumbled upon a ferry that travels from North Sydney, Nova Scotia to, lo and behold, Argentia. There were rental cars available in North Sydney so my colleague and I flew directly there, picked up the car and immediately took it on the ferry across to the island. We were able to get a room on the ferry itself with 2 beds, a bathroom, and the best view of the ocean. This was ideal as the ferry is about 16 hours long, overnight, so the bed was very much needed. 

Once arrived, we got settled in the town of Placentia, which was a short drive to/from the field site which was in the port where our ferry was docked. They had a cool lifting bridge that was a great backdrop for determining when the fog was rolling in. We did most of our experiments back at our arrival dock.  It was originally a World War 2 airfield site owned by the Americans, given by the British for the sole purpose of making it a Naval airbase. The Atlantic Charter was signed just outside the port which was thought to lead to the United Nations Charter (https://www.hiddennewfoundland.ca/argentia-naval-station). As someone who loves reading history, it was amazing to do the experiments in such an area. We were on one of the old runways as it was perfect for pointing the lasers in a way determine how far the lasers could travel. This was the goal for the first day on the site.


As always, something will go wrong on the field site and that was the case on our first day. When we first started testing, we expected to fiddle with the image parameters, such as exposure, to see the laser. However, no matter what we did we could not see any of the lasers in the images. We had not brainstormed what would happen in this case so we took a rather long lunch break to think about what we could do to mitigate the problem. We decided to try taking images anyways in the sun and increased the number of images taken for each laser configuration. The sun might be so bright in the day that the camera simply cannot view them in the image. We also decided to do some trial runs when it got dark. One evening, the fog rolled in so heavily that I got MAPLE all set up late in the evening. It got so foggy that it truly felt like I was in a horror movie or unsolved mysteries as I was unable to see a few feet in front of me. Images of what MAPLE could see in the dark showed how important the dark was to our experiments. After gathering a variety of images, we knew what the game plan was for the rest of the trip. 


We finished our Newfoundland trip with images in both day and night that will be analyzed further. Many questions were both answered, and the trip was extremely useful on telling us how we need to prepare MAPLE for the Arctic. The trip was a challenge but a great way to gain leadership experience. Since I was not the only person on this trip, Grace has these words to say about her time on our field trip:

“Most of the research I’ve completed throughout my degree has consisted of analyzing data acquired from space missions – whether that be temperature, data or pictures taken from the surface of Mars. Because of this, my days usually involve sitting at my computer, writing code, and generally not moving around too much. Going to Newfoundland for fieldwork allowed me to explore different facets of research that I usually do not get to explore. Working with MAPLE meant driving out to the field site in the mornings, setting up the instrumentation, and taking several experiments to try and capture the science. There is a degree of unpredictability with fieldwork that we don’t normally experience in our day-to-day work. Will it be foggy enough? Will the batteries have enough power for the experiments? Will the inside of the instrument get too humid? Carrying out this fieldwork was a very unique experience, and I am so grateful to have had the opportunity to try something new!”

 

Tuesday, August 9, 2022

Five Pictures from Ten (Earth) Years of Curiosity

 

The photos that our robot geologists (and robot atmospheric scientists) bring back to us from other worlds help us to relate to these places on a human scale. No one at the PVL have looked at more images of Mars than Alex and so, who better to take us on a visual trip down memory lane on this auspicious anniversary?

By Alex Innanen

August 6th marks 10 (earth) years since Curiosity (AKA the Mars Science Laboratory or MSL, because space people love a good acronym) landed in Gale Crater on Mars. If you’ve been around the blog, you’ll know that many PVL-ers have had the chance to work on the mission (myself included) and there have been a plethora of posts over the years about what doing ENV operations is like, or what cool science MSL is doing, or other big mission events, like the 2018 global dust storm or passing 2000 sols on Mars. To add to this collection, and to celebrate 10 years of Curiosity (or 5 Mars years, a milestone reached this most recent January), I’m going to journey through some of my favourite pictures the rover has taken over the past decade.

First we have the above picture, a classic selfie. Curiosity regularly poses for MAHLI (the Mars Hand Lens Imager) to take these self portraits, which are actually mosaics of tens of MAHLI images. There’s a fantastic video of Curiosity’s arm moving around to get all the pictures that make up a selfie. This particular selfie was captured during the 2018 global dust storm, and you can see dust in the background obscuring the crater rim. This is the same dust storm that heralded the end of Opportunity’s mission, but Curiosity came through with lots of science (and nifty pictures) to show for it.

Going all the way back in time to 2012, this is a 360° panorama of Curiosity’s landing site, named ‘Bradbury’ for the sci-fi author Ray Bradbury. Right in the centre of the picture is Mount Sharp (or Aeolis Mons), the mountain in the centre of Gale Crater. Mount Sharp is made up of sediments laid down in Gale Crater over a long period of Mars’ history, and as Curiosity has climbed up it, it’s as though the rover has been travelling through that history. But first it had to get to the base of Mount Sharp, a trip which took around 2 years trundling through the remnants of ancient lakes and rivers. I love looking at this panorama because it gives a great idea of how far Curiosity has traveled – over 28 km and 600 m of elevation, now. It's also a great ‘big picture’ shot – every new location Curiosity visits is (in my humble opinion) stunning and unique in its own way, with so much new and exciting to look at. This image lets you take a step back and take it all in.

It would be remiss of me to not include a cloud picture, so here it is, my absolute favourite cloud shot. I may be slightly biased, as I was on shift when this image was planned, but it’s so dramatic, with the cliff face (called ‘Mont Mercou’) in the foreground and the glowing clouds behind. These are Noctilucent clouds, which means ‘night shining’, and were captured at twilight early this Mars year (which was actually March of 2021 – Mars years are long). These kinds of clouds are high up in the atmosphere, and are illuminated by the setting sun, even visible when the sun has gone below the horizon. This is what makes them appear to glow, still being illuminated while the rest of the sky darkens. These particular twilight clouds seem to form more readily in Gale crater near the beginning of the Mars year, something the team discovered in Mars year 35. At the start of Mars year 36 (the current Mars year) we started looking for them and were not disappointed. One of the great things about Curiosity having been on Mars for so long is the fact that we can see yearly repetitions like this and come up with a better idea of what the Martian environment is up to year after year.


Mars’ blue sunset is spectacular and well known to fans of the ‘red’ planet. But “what colour is the Martian sky?” is a question I’ve been asked more than once by those less familiar with Mars. And it’s a great question! Sometimes – like in this picture or the cloud picture above, the sky looks more blue, almost like earth’s sky. But at other times, like in the selfie or the Mount Sharp panorama, it looks more orange or yellow. There’s a few factors behind this – often images are colour-corrected (‘white-balanced’) to show what a scene might look like under earth-like lighting. This can help scientists interpret features within a scene, making them look more familiar to better compare to earth, but doesn’t accurately represent what you might see if you were standing on the surface of Mars, which would be more of a yellowy-orange sky.

Except when you get close to the sun, like in this sunset picture. Much like how earth’s scatters light, giving us a blue sky, so too does dust in the Martian atmosphere, but the blue wavelengths of light mostly scatter forwards, so the blue colour appears closer to the sun. As the sun sets, there is more atmosphere and more dust for the light to scatter through, so that blue effect near the sun becomes more pronounced. 


I’m going to finish with this absolute stunner of an image, which combines two NavCam (Navigation camera) mosaics of the same scene, one taken in the morning and one in the afternoon. They were combined to show different landscape features that are highlighted as the sun illuminates some regions and casts others into shadow. After talking about the colours of Mars, you may be wondering what gives this image its striking blue and yellow palette. The NavCams on Curiosity only take pictures in black and white – colour was added to this image after the fact to highlight the lighting changes, with blue showing morning features, yellow showing evening features, and their combination showing just that – a combination of the two. This picture is looking back down Mount Sharp towards the crater rim in the distance, and it seems like a fitting image to close this blogpost on, looking back over the last great 10 years with Curiosity.

Sunday, May 29, 2022

Science is for all of us!


 This week on the PVL Blog Post, MSc student Ankita talks about citizen science, a way by which anyone can participate in scientific research and discovery.
Image Above: YorkU Galaxified Generate your own text at: http://writing.galaxyzoo.org/

By Ankita Das

Being someone who developed a keen interest in science at a very early age I was always looking for new ways to learn and contribute to the science happening in the world. By the time I was in my early teens, citizen science projects were my favorite way to spend time when I was not involved in academic work. I spent my winter of 2010 sending my friends and family a personalized season’s greetings. Except, there was something special about these messages – the text was “galaxified” using GalaxyZoo’s special tool where each letter was a galaxy from the Sloan Digital Sky Survey (SDSS). These were the little ways I would incorporate space into my daily life. But my love for science at that age went beyond generating cute galaxified texts.


Citizen science is often someone’s first introduction to hands-on science. Personally, my first citizen science projects were in Galaxy Zoo and Planet Hunters by Zooniverse. The Galaxy Zoo project involved classifying galaxies into categories by looking at its shape - something even a child can do but holds valuable science behind the activity. A lot can be revealed about a galaxy just from its shape. For example, an elliptical galaxy is usually an old galaxy where no active star formation takes place and spiral arms in a galaxy imply a rotating disk of stars. The shape classification were according to Hubble’s classification scheme shown in image 2.

 

Image 2: Hubble’s Classification Scheme for galaxies (Source: Wikipedia Commons)

Apart from classifying galaxies imaged by SDSS, my other favorite go-to project involved looking at light curves from distant exoplanets being discovered by Kepler. Kepler’s launch in 2009 marked the beginning of some very exciting exoplanetary science which continues till date. The task at hand was again simple: to look at the brightness of a star over time and determine if there are any periodic dips in the brightness indicating the possible presence of an exoplanet around the star. The excitement I felt as a young teenager “analyzing” data from a telescope launched just a year before, possibly discovering new alien worlds was unparalleled. Participating in citizen science initiatives back then gave me a sense that I was doing something important for the scientific community even as a kid. 


Image 3: Example of Planet Hunters task
(Source: https://www.zooniverse.org/projects/nora-dot-eisner/planet-hunters-tess)

Citizen science has become an important facet of research in the scientific community today with it having evolved into more creative and interesting projects as new troves of data are generated. Citizen science projects can range from activities as simple as locating constellations with your naked eye monitoring light pollution (Globe at Night) to projects that involve amateur astronomers, photographers, and programmers equipped with certain level of hardware or skill to carry out the science. In this way, citizen science involves diverse groups from our society ranging from kids to amateurs to take part in various citizen science initiatives. For the younger section of the public, citizen science projects can become their introduction to scientific projects whereas it can be a leisure activity for the relatively senior members of our society. To me, citizen science initiatives are a powerful and effective tool for scientific outreach. Not only do members of the public learn about the science that is being carried out, they also actively contribute to it, developing a deeper interest over the years in such projects. Irrespective of the diversity in participation, one thing remains the same, all these groups contribute to our growing scientific knowledge about the world around us. 

But can the general public really contribute to the cutting-edge fields in science from their homes or backyards? Yes of course! Over the years, citizen science has churned out an interesting list of discoveries which have made it to scientific journals after being reviewed by scientists. One of the most notable discoveries in the field of space science which comes to mind is the discovery KIC 8462852 or more colloquially known as Boyajian’s star (named after Tabetha Boyajian, other names include Tabby’s star and WTF star). In 2015, citizen scientists who were part of Planet Hunters came across a star exhibiting odd levels of dimming (22%). Upon closer inspection by astronomers, the object’s odd behavior continued to baffle them leading to many people calling it by its nickname – the WTF star which is apparently a reference to the paper’s subtitle: “where’s the flux” (very misleading nickname, I know!). Scientists came up with various hypotheses to explain the star’s observed light curve which included possibilities of obstructions around the star occurring from a ring, planetary debris, or dust clouds. More farfetched hypotheses included the presence of large-scale artificial structures around the star being responsible for the unnatural dimming of the star’s brightness, hinting at the existence of intelligent civilizations. Scientists continue in their attempts to fully understand this bizarre star and hence Boyajian’s star is still being studied and monitored by subsequent telescopes and projects. 

I think most of us would agree science has changed a lot since ancient times. Science which started off as independent endeavors taken up by philosophers centuries ago today presents a different picture. The days of sitting under a tree and pondering on the mysteries of the universe and scribbling down equations are long gone. Most science carried out today is in large groups, relying on observed and measured data retrieved from instruments such as telescopes, particle accelerators, and robotic spacecraft. Hence, a huge amount of data is generated and will continue to be generated as next generation telescopes come into operation. Citizen science initiatives are a fantastic way of tackling this big data problem astronomy and space science is to expected to face soon. Thus, citizen science is not only valuable for outreach but also valuable in processing huge chunks of data and making meaningful contributions to the scientific community. A complete list of active and inactive citizen science projects in all scientific fields can be found at: https://en.wikipedia.org/wiki/List_of_citizen_science_projects

Read more at:
https://www.zooniverse.org/projects/zookeeper/galaxy-zoo
https://www.zooniverse.org/projects/nora-dot-eisner/planet-hunters-tess
https://www.darksky.org/globe-at-night-2021/
https://science.nasa.gov/get-involved/citizenscience/five-extraordinary-citizen-science-discoveries
Boyajian’s star discovery paper: Planet Hunters X. KIC 8462852 - Where's the Flux? Available at https://arxiv.org/abs/1509.03622

Sunday, May 1, 2022

I know what you did last summer: Grad School Edition

With May having just begun, undergraduate students are looking forward to the summer, but the situation is different for Professors and graduate students. Though few grad students take courses during this time of the year, it is nevertheless one of the busiest times of the year. Below, MSc student Justin Kerr explains why and describes some of the rhythms of graduate student life.

By Justin Kerr

“So, you are a student right? When does your summer break start?” It’s only April, and I’ve already been asked this question dreaded by graduate students everywhere three times. At least it’s not as bad as when I was on the hunt for an apartment! When you first become a grad student, you quickly realize that most people outside the realm of academia don’t understand what research based graduate school in the sciences entails. In reality, we are typically enrolled in few if any classes and most certainly do not get a multi-month vacation in the summer months. Course-based graduate programs do exist, but are much less common in the sciences and are typically excluded from receiving most of the normal funding. So, what do research-based grad students in physics actually do?

While grad students do take some courses, they typically make up the smallest portion of our time commitments throughout the degree. Here in the Physics and Astronomy program at York University, Master of Science students have the choice of pursuing a degree by thesis or a research project. In the case of a research project, students are required to take five one-semester courses throughout their two-year program. This type of degree is more common in physics programs for students looking to pursue a PhD at the same university in order to reduce course load during their PhD. It gives more variety in topics studied but allows less time for research. By the end of the degree, students are expected to have completed an original research project presented in the form of a large written document (although often somewhat shorter than a thesis). This type of degree is more common in some specific fields than others; for example, it is almost always used in particle physics, but is a rare choice in our own lab group. Personally, this is the option which I chose in order to expand my expertise in different areas of physics to support my future goals in academia. While this is the high course load option, it still means taking very few courses – the equivalent of a single semester in undergrad over two years, at least without compensating for enhanced difficulty of the material.

The thesis option instead requires only three courses be taken over the same two-year period. This allows students more time for research and development of a more intensive project. A thesis is typically longer than a research project and may involve more multiple smaller projects rather than the single one described in a master’s research project submission. Theses are also presented in a formal defense process instead of a simple submission to a supervisory committee. Completing a thesis gives a more complete research experience to students, which is more heavily valued in certain fields. In straight physics degrees, this can also be used as an option for students who are not intending on continuing in academia to provide a more complete education prior to moving to industry. Some universities other than York have very strict preferences for which type of degree is completed for moving forward in a PhD program, such as physics programs at the University of Toronto. When completing a PhD, the only option available is a thesis, and it will be much more intense than the MSc version. At York, a physics PhD requires the completion of six graduate courses, including any taken during the MSc – meaning a student who used the thesis option will take three courses throughout their four-year degree, and research project students will only need to take one. This means that thesis and PhD students are often not taking any courses at all in a given semester, and usually only one at a time if they are.

The main goal of a graduate degree in the sciences is to perform the research that will become the research project or thesis. To properly do this, we need to first perform literature searches and read many scientific papers pursuant to our planned project. We also keep up with relevant new research in our fields by reading new publications, with most graduate students often reading through several scientific publications per week. The bulk of our work is to perform our research tasks. In physics, this usually means coding, lab experiments, or some combination of the two. This is the portion of our responsibilities that means we don’t have a summer vacation! When other responsibilities do not get in the way, we are working on our research. Producing publications is also an important aspect of graduate education, which when combined with thesis requirements ensures that a good portion of our time is spent writing. We are generally expected to work roughly full-time hours (although deadlines often have something else to say about that!), with research and the associated writing taking up most of that.

The final portion of a graduate student’s responsibilities is teaching assistant duties. As part of our admission agreement and making up about half of our yearly funding are contracts to be teaching assistants for courses offered by our department or that of Natural Science, which covers science electives for non-majors. These can include grading assignments, teaching/demonstrating in a lab course, or leading tutorial sessions in undergraduate classes. The standard requirement for TAing is 270 hours per year, which usually averages out to about 10 hours per week during the Fall and Winter semesters while leaving the summer free to focus on research. In reality, much of that often ends up being concentrated into a few very busy weeks around midterm and exam grading time.

While a good portion of our funding comes from the relatively small portion of our work that is TAing, the truth is that the vast majority of our time spent on research is in fact still work. Since any of the few courses we do take usually occur during the Fall and Winter semesters along with our TAing, our summers are left free not for a summer vacation as it might for undergraduate students, but instead for a large focus on our research work. This is particularly important for those of us graduating in August such as myself who are likely to have some of the busiest months of our degrees ahead of us while we try to perfect our research projects and theses ahead of submission deadlines and defenses. The start of the summer is no better, with the start of May meaning research evaluations for all of us; these are where we must present our current work and future plans to our supervisory committee in a form of oral exam. The next time you are chatting with a grad student, make sure not to assume that they are looking forward to their nice summer vacation to take a break from the courses that they are likely not even taking!

Thursday, April 28, 2022

What Has the James Webb Space Telescope Been Up To?

PVL MSc student Madeline Walters has been following the launch and deployment of the James Webb Space Telescope with bated breath. This observatory will be a boon not only to the astronomical community, but also to the planetary science community. Above: the telescope's alignment evaluation image catches not only the target star, but myriad faint galaxies in the background.

by Madeline Walters

Since my last post about the James Webb Space Telescope (JWST), the telescope has reached its observing point and made some initial observations. The Webb is currently in orbit around L2, the second sun-Earth Lagrange point which is a gravitationally stable point about 1.5 million kilometers away from us. Since its launch, the spacecraft has gone through a few metamorphoses in preparation for its eventual observations. From testing a key antenna, to deploying its sunshield, each movement and maneuver has been integral to the telescope’s success. After successfully deploying the structure that binds the Webb’s two halves together, there was enough room to begin unfurling the massive sunshield that protects the telescope from harsh radiation. 

Soon after the sunshield was fully unfolded, the Webb deployed its two sunshield mid-booms, which stretched the sunshield out to its full length. This process requires the membranes to stretch to their proper tension, taking up to two days to tighten the sunshield. "As photons of sunlight hit the large sunshield surface, they will exert pressure on the sunshield, and if not properly balanced, this solar pressure would cause rotations of the observatory that must be accommodated by its reaction wheels," writes NASA public affairs specialist Alise Fisher in a blog post on December 30 after the launch. "The aft momentum flap will sail on the pressure of these photons, balancing the sunshield and keeping the observatory steady." It is a lot of very intricate and detailed steps that are necessary for every step of the operation-and for good reason. Every part of the unfolding must work in order to get the Webb to start observing. 

The next crucial part of the mission was the mirrors. On January 5, the telescope deployed its secondary mirror, unfolding a series of booms that hold the mirror out in front of the main mirror. This secondary mirror allows light to be collected and focused into a beam, which is then pushed down through the center of the telescope to a third mirror and other smaller ‘fine-steering’ mirrors which allow light to be properly allocated into the scientific instruments. 

Several days after the secondary mirror was deployed, the main mirror’s side panels were deployed, gearing up for the alignment of all 18 individual mirrors that make up the entire main mirror. And if you don’t think the word ‘mirror’ has been said enough so far - the observatory team spent about ten days working to move each mirror segment out of their preliminary launch alignments, and a lot longer for more precise alignment after that. However, for an instrument that will bring us observations for perhaps up to 20 years, a few months of alignment is worth it. 

Now at its destination for its science mission, the Webb has woken up, turned its instruments on, and has looked out into space to provide us with its first images. Its first telescope alignment evaluation image, made to only focus on the bright star in the center for alignment evaluation, shows background stars and galaxies due to the telescope’s optical sensitivity. Although there are still many months left before the JWST delivers its first full view of the cosmos, the telescope has already gone through an incredible journey made possible by an incredibly patient group of engineers and scientists.