For the Love of Science

While studying Pluto craters, I was faced with a somewhat confounding question: how would a crater form if you have a thick layer of volatile (methane or nitrogen) ice overlaying the much stronger water ice bedrock. I’ve been studying crater degradation, and it’s important to know the difference between a crater that has degraded vs a crater that just started degraded. That is what brought me to this, not so recent paper, Senft and Stewart (2008) that studied what water ice layers, at the surface and in the subsurface, do to the morphology of an impact crater that forms.

They studied a range of scenarios, but I want to focus primarly on the water ice surface and subsurface morphologies, at impact and right after impact. They assume the bedrock is basalt and the ice is water ice; they list the all the variables within the model (CTH, a Eulerian shock physics code) in their paper. Naturally, the strength of the material plays a major role in what the final morphology will look like, but the melting temperature (or pressure?) is also an important factor. That seems to be a major reason for the variations in morphology.

Ice appears to limit the lateral propagation of the shock wave/pressure, yet it enables larger shock waves to extend deeper down, on the hole. The highest pressures are not present in the water ice, but the smaller, but still large, pressures extend further. Of course, the net results is simply less extreme pressures at the bedrock surface. The addition of a subsurface layer interferes with the pressure wave but not as significantly. The ice seems to experience heating over a larger surface area, but the extremes are not as large as in the bedrock. Perhaps it relates to phase change (I don’t quite remember what they say in the paper). There should clearly be vaporization and melting of the water ice (almost all of it in fact), and that likely feeds into the morphologies they observed.

A change in morphology is almost inevitable when the pressures are reduced. The first thing that occurs is the formation of a less distinct rim, even with their thinnest ice layer (100 m). However, the rim that does form is sufficient to prevent the surface ice from (at least immediately) flowing back into the crater. However, there seems to be a critical thickness (maybe ice thickness > 0.5*crater depth) where the rim cannot prevent the surrounding ice from flowing back into the crater. It is almost fluid in nature, and perhaps it is, given the temperatures they predicted. I’m curious whether that fluidity would have happened if the ice was not melted. Naturally, I can’t help but wonder if this is applicable to a Pluto scenario with bedrock water ice and a surface volatile ice layer. See my paper for more discussion of that.

The team also considered a subsurface ice layer of varying depths and thicknesses. This scenario is interesting because I had suspected these morphologies for Pluto when I first started considering what craters would look like in volatile ice over stronger bedrock water ice. I thought the depression would leave volatile ice residue in the basin and on the walls, but that seems to only happen for subsurface layers. I suspect it relates to the bedrock basalt acting as a blockade to the surrounding ice, until a critical thickness is reached for surface ice. While in subsurface ice, the hinging of bedrock basalt does less to block the ice than it does to open the way for it like a door swinging open. The craters begin degraded with water ice in the base. As the layer thickens, the crater becomes less and less observable, but there is a characteristic sloping of the bedrock layer. This is an interesting observation that would be cool to observe directly.

Big picture, it is clear that volatile ices/layers can affect crater morphology. This isn’t exactly news as marine impacts produce similar results (Bray et al., 2022). I think it would still be advantageous to pursue this problem for Pluto specifically, but even the Mars work may be in need of a refresh given it has been nearly a decade an a half.

As the days go by, we get ever closer to my defense date, and consequently, the thesis submission dead line (July 12th). My research update is that I am busy writing.

I suppose I could end the blog there, but I will go a bit deeper. My introduction chapter is in its first draft, and I will start editing it in the next week or so. My first main chapter was published earlier this year so is thankfully finished (Hedgepeth et al., 2022). This was my work modeling the emplacement of HCN into a freezing melt lens on Titan. HCN acted as placeholder for the larger population of organics we expect to find on Titan. However, more work is needed to constrain this complex process.

My 2nd main chapter is not submitted but is largely finished. I need to edit comments from my coauthor. However, the paper is probably far enough along to be dissertation material, so it is my lowest priority at the moment. This chapter is studying the degradation of craters on Pluto. It does not revolutionize our understanding of Pluto, but it does provide unique context of the state of the various geologic groups across its surface. I was nervous going into this one. I love Pluto, but I don’t have the kind of background with it as I do with Titan. The reference list ended up being extremely long as I was excessively making sure I understood what I was talking about, and our coauthor seemed to like it. That bodes well. I’m excited to submit it soon enough and officially be a part of the Pluto community.

My third and final main chapter is actively being written. I don’t expect it to be as intensive as the other two papers partly because it is a continuation of the paper published earlier this year. Nevertheless, I am hoping to get the majority of it written this week. I say the majority because there is still a bit of research left to do. I’ve modeled glycine like I did HCN, but I now want to consider what the distribution might look like if HCN is being removed (i.e., a mass sink) or glycine is being added (a mass source). This is still limited as we are treating them as independent mixtures when in reality the properties of the mixture will be modified by the presence of each molecule. We’re considering it by estimating the mass sink or loss as an exponential decay (you can find my abstract from AbSciCon). The current issue is we need to export the mass removed from HCN into the glycine model through time. This is requiring a moderate change to the 2D model we use which is why I am focusing on writing up the rest of the paper, including the results I currently have.

That then leaves a discussion and conclusion chapter which will be far less intensive but not exactly easy. The current plan is to finalize the first draft of the hydrolysis paper (mention in the last draft) the week of 6/8 (this week). The next modeling work should be ready to go by the end of this week. While I run those models, I will spend next week revising the intro chapter, with the last two weeks of June to write the Discussion and Conclusion. Hopefully, Catherine will be able to get me feedback on the revised introduction and hydrolysis 1st draft by that time, giving me a couple weeks to make final revisions on those before submission. I don’t expect the discussion and conclusion to require extensive edits.

Big picture, things are getting down to the wire. I’ve laid out the plan, but I’d be lying if I said I wasn’t nervous. There is still a lot of writing to do. To quote Meryl Streep, I have doubts, but I’ve doubted myself since childhood. That hasn’t stopped me before, and it won’t stop me now.

I recently got approved to review an audiobook ARC (advanced readers copy) of 1984, published by Dreamscape Media and narrated by Peter Noble. It was one of those in the moment type requests, and even after I was quickly approved, I began to stress about when I’d actually get to it. Little did I know, I’d finish it within a week. This isn’t intended as a review of this edition (check my Goodreads for that), but I mention it because I want you to understand why I went from feeling regretful on the request to plowing through it. The narration was great, of course, but to be honest, if I didn’t like it, I could have listened to enough to review it and then switched to a narration I did like (I initially listened to, and loved, the Frank Muller rendition). Imagine my surprise when I found myself unable to stop listening. It’s been anywhere from 6 to 12 years since I’ve read it (sometime after high school but before grad school), and boy what a difference a decade makes. Don’t get me wrong, I loved it my first read through; it’s a very compelling book in its own right. However, I don’t think I fully appreciated the deeper message within it. That is what prompts this post (that and the group meeting that requires me to write a post). Forgive me if it’s a bit rushed.

Many people, across the political spectrum, love to reference 1984. It is so very quotable, and ironically, it’s easily weaponized to push the very mindset it seeks to fight against. Let’s start by considering the notion of a thought crime.

Freedom is the freedom to say that two plus two make four. If that is granted, all else follows

Not merely the validity of experience, but the very existence of external reality was tacitly denied by their philosophy. The heresy of heresies was common sense.

I’m sure there are transphobes who would appeal to “2+2=4” when denying the reality of gender as a spectrum. Except, the notion that gender is as simple as 2+2=4 is itself a rejection of one reality in favor of another. The irony here is the sudden love of science despite the often disinterest in science when it isn’t useful to them. The notion of freedom is easy to appeal to, but it misses the fundamental message of the book. It refuses to look at the reality of their own claims. The “reality of gender” is an assumed truth. It is a basic piece of knowledge, as they see it, that was taught to them from the moment they were born. In being unwilling to challenge that very notion, you are falling into the very way of thinking that exists in 1984. It’s not that gender as a spectrum is necessarily the truth. It’s about challenging the existing power and knowledge structure, using the truth of reality, outside our own minds, to come to the actual truth.

Don’t you see that the whole aim of Newspeak is to narrow the range of thought? In the end, we shall make thoughtcrime literally impossible, because there will be no words in which to express it.

Then there is the problem of appealing to thoughtcrimes anytime a harmful comment is made. This is often called cancel culture. The entire notion of cancel culture is ridiculous. Celebrities and politicians use the phrase to claim being attacked whenever they’re held accountable. In reality, those who become “canceled” never actually lose their power or money. They always come back to the fold, some not leaving at all. It is, in many ways, being framed as a thoughtcrime to hold any idea that doesn’t fit the norm. This is a flimsy line of logic, not the least of reasons being these are individuals, not the government, calling these people out. It’s also about the fact that it is more than a thought. These are substantial claims and actions being made. Tucker Carlson advocates to his entire audience as series of objectively harmful mindsets, that don’t just create division, it motivates hate (in mind and action). Of course, he is intentional. Maybe there are others likes of JK Rowling who genuinely believes they are in the right. Except, they still spread hateful thoughts. What’s more, they often become weaponized by more intentionally hateful groups. At the end of the day, it’s about more than accountability; it is a way to challenge the existing structure of power that exists within society. The right to exist with counter views has not been challenged.

However, before we get to power, let’s extend the discussion of cancel culture to a broader one that relates to the reframing of how we remember history.

Every record has been destroyed or falsified, every book rewritten, every picture has been repainted, every statue and street building has been renamed, every date has been altered. And the process is continuing day by day and minute by minute. History has stopped. Nothing exists except an endless present in which the Party is always right.

Who controls the past controls the future. Who controls the present controls the past.

When statues are taken down or significant figures of history attacked and reframed, is it as simple as rewriting the past (lets ignore that no one is changing the textbooks—except for those striking them of uncomfortable history, cough cough Texas— and lets ignore that the goal is not to erase them but to stop worshiping them)? It’s easy to pull a quote and claim that we are rewriting history because it makes us uncomfortable or because we want to forget it. Although, the truth is that these are not true representations of the actions being done.

There was truth and there was untruth, and if you clung to the truth even against the whole world, you were not mad.

It is easy to side with Winston in 1984 because we know he knows the truth. We know that Big Brother has, and continues, to rewrite and erase what has happened, but image if you were within this society. Winston himself breaks in the end, but suppose you knew the truth. Suppose in fighting for it, you were cast as the untruth. We live in a country controlled, throughout most of our history, by straight white men. Big brother, in a form, has already been in control. Big brother has already written the books we learn from. Is it rewriting the past to cast doubt on the history that’s been presented to us? Who wins in a world where the US is presented as a racist, sexist, homophobic monster? The minority. We return again to the quest for equality and the breaking of the power structure.

The Party seeks power entirely for its own sake. We are not interested in the good of others; we are interested solely in power, pure power. What pure power means you will understand presently. We are different from the oligarchies of the past in that we know what we are doing. All the others, even those who resembled ourselves, were cowards and hypocrites. The German Nazis and the Russian Communists came very close to us in their methods, but they never had the courage to recognize their own motives. They pretended, perhaps they even believed, that they had seized power unwillingly and for a limited time, and that just around the corner there lay a paradise where human beings would be free and equal. We are not like that. We know that no one ever seizes power with the intention of relinquishing it. Power is not a means; it is an end. One does not establish a dictatorship in order to safeguard a revolution; one makes the revolution in order to establish the dictatorship.

I hope by this point you can recognize how the Big Lie comes into play here. What is the central purpose of Big Brother? Power. The entirety of the system exists to control and to retain power. This could be applied to any politician—at least it could be asserted, but at the end of the day, the Big Lie presents us with the ultimate recreation of Big Brother. “Who controls the past controls the future. Who controls the present controls the past.” “There was truth and there was untruth, and if you clung to the truth even against the whole world, you were not mad.”

What can you do, thought Winston, against the lunatic who is more intelligent than yourself; who gives your arguments a fair hearing and simply persists in his lunacy?

This is the very circumstance we find ourselves in today. Perhaps you are a proponent of the Big Lie. Maybe in your eyes, I am the lunatic and you exist free of Big Brother.

For the first time, he perceived that if you want to keep a secret, you must also hide it from yourself.

Donald Trump need not accept his own lie, because he has no interest in the truth. He never has. He has only ever concerned himself with power. However, his followers must believe the Big Lie if they are to exist within his reality.

It doesn’t matter how many courts (of varying political leanings) discount the unsubstantiated claims. It doesn’t matter what evidence exists or fails to exist. The message is the truth.

Doublethink means the power of holding two contradictory beliefs in one’s mind simultaneously, and accepting both of them.

And if all others accepted the lie which the Party imposed—if all records told the same tale—then the lie passed into history and became truth. 

When the Party/Big Brother/Trump becomes the basis of truth, you lose any interest in other ways of reaching the truth. Then the truth becomes whatever he asserts is the case. If he contradicts himself (STOP THE COUNT! COUNT THE VOTES), it somehow isn’t an issue.

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I know I didn’t have a good overarching story for this post. It was more that I had a series of thoughts that I wanted to explore because 1984 is as relevant today as it always has been, but it’s important to think about it in the ways it’s being embodied but also misapplied. Otherwise, to be Orwellian loses its significance.

What an astonishing thing a book is. It’s a flat object made from a tree with flexible parts on which are imprinted lots of funny dark squiggles. But one glance at it and you’re inside the mind of another person, maybe somebody dead for thousands of years….Books break the shackles of time.

Carl Sagan, Cosmos: A Personal Voyage

I suppose this clip or quote summarizes this post pretty effectively, almost to the point that I have to ask if it even needs to be written. Nevertheless, I felt compelled to write it, and now you are compelled to read it, entering into my mind, hearing the words as I did as I typed them. The concept of books breaking the shackles of time is pretty straight forward, but I would like to explore it a bit further, delving into a discussion of time, consciousness, and what it means to enter the mind of a writer. In short, I’m going to seriously overthink it.

It’s no secret that I am a massive fan of time, both in fiction and reality. The entire concept has amazed me since I was a teenager when I first learned of relativity and the nature of space-time. Since then, I’ve learned a great deal more, including the concept of the externalist (or block) universe. I’ve discussed this, not that long ago, so I won’t fixate too much on it here. However, I wanted to revisit it because I think the implications make books more of a form of time travel than we realize.

The nature of time in a block universe makes every point in time equal to the rest. The notion of time flowing is purely a function of how our brains interpret reality (likely because of entropy). Therefore, when we think about a moment of time in two ways: 1) as a configuration of matter within space and 2) a unique impression made upon our brains to define the experience of that moment. We cannot easily recreate the state of the universe in the past, nor are we likely to find ourselves (i.e., the current configuration of matter that composes us) inserted into that slice of time. All we have to go on are the lasting impressions that moment of time made on the universe. We can recreate a picture of that time in the same way that geologists can recreate the picture of Earth in the distant past. However, that is not the same as truly experiencing it. We can understand it, but it will never replicate the conscious experience of being there, while reading can.

When we read the words of a book, we’re seeing the inner dialogue that an author has in their mind as they right it. We are recreating the internal experience of that moment. This is most true in nonfiction, whether it be a memoir or even any other sub-genre. Newton’s Principia Mathematica doesn’t just communicate science, it communicates the inner workings of his mind in the moment. Even in fiction, we are seeing the imagination created by the imprints of their surroundings. We could read ancient literature and enter the mind of Homer over 2500 yrs ago. The story has been retold and translated, filtering the experience down, but at its core is a section of thought impressed by the world in 600 – 800 B.C.. Books are an impression of a fraction of an author’s mind, but what does it mean to experience a moment if not to form a compendium of impressions? It’s a hazy recreation of a moment of the past. Therefore, to read is to travel back in time.

Books are an impression of a fraction of an authors mind, but what does it mean to experience a moment if not to form a compendium of impressions?

Let us be clear. I am fully aware of how hand wavy this entire discussion is (to the point that I’m a little embarrassed to share it), but if one truly wishes to travel back in time, reading is one of your best ways of doing it. It isn’t the only reason to read. However, I think it can be a fun and exciting way of approaching some forms of reading. Every classic work is more than a piece of entertainment. It’s a portal back in time. If you had the option to travel back in time (safely and with confidence that you can return) would you not take it? I certainly would, and it’s part of why I read some classics. It’s also why I’d like to eventually get to more ancient literature of which I’ve read very little. Ignoring high school, the furthest back in time I’ve traveled is ~1000 A.D. with the Tale of Genji, and I am itching to take the machine even further back. Of course, I can’t stop with just one book. Remember, a moment is defined by a collage of impressions. True time travel requires we take in multiple impressions which means exploring multiple works.

In the end, this is nonsensical. We can’t travel back in time (yet at least), and I know that. I wish to be very clear that I’m being purely metaphorical (in case any random readers stumble upon this post and think I think this is real). It’s strictly intended as a way to excite myself and other readers into reading more and exploring different types of works.

Intro

In this post, I will be reviewing and summarizing the paper, Impact Craters on Pluto and Charon and Terrain Age Estimates (Singer et al., 2021). It is a part of the University of Arizona Press book, The Pluto System After New Horizons (reference at the end of the post). If you’re interested in reading more accessible papers on Pluto’s craters, you can check out this review of the population, this review of their depths and morphology, or this review of cratering rates. The paper I am reviewing is a part of a book of papers written to summarize recent findings in the Pluto-Charon community. Therefore, everything that’s discussed here is really just pulling from papers like those I’ve linked to. Note, I will be primarily focusing on the Pluto results. There is naturally more about Pluto in most of these papers, but it is also what I am most interested in. Feel free to check out the paper/papers if you want more details on Charon.

Perhaps the most significant thing we gained from the study of Pluto’s craters was a better understanding of its geologic history. Prior to New Horizon’s, it was unclear if we would find any craters on Pluto because of the types of processes that were predicted to possibly be occurring. What they found was more of an in-between state. Pluto’s surface has a diversity of crater patterns that highlight the vast range of geologic processes that occur across its surface. It leads to a world with valuable information on the origin of the solar system and the various impactors that have collided with it, but superimposed in places are unique processes that reveal valuable information about Pluto’s history. That is one of the things that makes it particularly interesting to me because I am use to thinking of crater processes on a global scale. Titan has a range of crater morphologies due to varying amounts of fluvial and aeolian processes, but even this is a fairly ubiquitous on Titan. Then on worlds like Europa and Ganymede, where no atmosphere exists to modify the surface, viscous relaxation is the primary erasure and modifier of craters. Pluto on the other hand, has regions distinctly unique from the rest, as if moving from one to the other is moving between different worlds (or at least in my perspective).

Crater Morphologies

The basic shape craters make is a bowl, but they collapse due to material strength, gravity, and impactor energy. This happens in ice because it is much weaker than rock, even at these temperatures (10s to 100 K). Therefore, craters on Pluto are similar to those of other icy worlds. They transition from bowls, to flatter complex craters with central peaks and potentially pits (though the latter is less abundant than expected). There are also two large basins on Pluto, one being the well known Sputnik Planitia and the other being the smaller (~1/3 the size of SP) Burney Basin. After formation, geologic processes can modify the crater shape. The primary form is through, erosion, relaxation, and infill (you can see my discussion of a paper on this here). However, these are largely volatile driven (methane, nitrogen and carbon monoxide ices), and Charon, less abundant in volatiles, has a more pristine crater population. One area this is particularly noticeable is in the lack of ejecta blankets on Pluto.

Crater Frequencies

Cthulhu is characterized by its dark (tholin layered) albedo, and it has areas that appear very ancient (heavily cratered) and smooth. However, its abundance of large craters (see the figure in Terrain Ages) suggests it is very old overall. The midlatitudes are suspected to be middle aged to old. There is a noticeable lack of large craters suggesting very early resurfacing (or mantling) as that is when newer craters would have formed (they could also just have not happened as frequently, by chance). There is some evidence of erosion (sublimation/ re-deposition). The fretted terrain shows signs of eroded valleys, with some navigating around craters suggesting the valley is young and the crust (ice base) is old. To the east lies the Burney basin. Apart from its rim, it is heavily cratered with a unique texture that is suggested to be very old (which is consistent with its high crater rate in the figure below. In the North, significant deposition and sublimation cycles are ongoing, modifying the surface, and the albedo of the craters are though to relate to volatile processes. Then there are several regions with minimal to no craters (see part b of figure in Terrain Ages). There are a couple possible cases in Eastern Tombaugh Regio (E_TR) and near Wright Mons (WM), but the authors seem less keen on marking a crater than I am (perhaps naively, on my part). Craters are fairly abundant on Charon, even the smaller ones (to an extent) that are lacking on Pluto, with the exception of a smoother darker terrain in the north. Overall, slope (i.e. the knee) of the R-plots suggest this says something about the impactor population and not just the geologic processes on Pluto.

Cratering Population and Rates

Pluto’s varying terrain types helps differentiate between the impactor population and the geologic history. However, calculating cratering rates is complex and difficult to constrain. First, it depends on the structure and history of the Kuiper belt. Currently, the prevailing theory is the Nice model of Planet Migration + Jupiter capture which in turn effects predictions for impacts early in the solar system. Even still, much of the predictions rely on the current knowledge about the structure of the Kuiper belt (believed to be the same for the last ~4 G.y.). Then, there is uncertainty in the distribution of sizes in the Kuiper belt that leads to uncertainty in the rates they measure. On average, an impact speed of 2 Km/s is used, but the range of populations in the Kuiper built can create a range of impact speeds as well. From there, a impact rates are estimated. Despite all the sources of uncertainty, the predictions seem to agree within a factor of 3 or 4 (translating to age differences on the order of 1-4 G.y.). Rates are calculating by scaling the impact rates and considering the target and impactor properties. However, it was unclear in the text whether they use a consistent water ice bedrock. I can’t help but wonder what would change if we consider thick mantles of volatile ices that would have significant differences in material properties. The predictions made leading up to New Horizon’s are shown in the figure above.

Terrain Ages

Terrain ages are estimated by using the measured craters and predictions for crater density of a terrain. It reflects the adding or removal of craters through resurfacing. It assumes all the craters observed are primary and not secondary (as there is no evidence of these despite the expectation that they would exist). Given all the uncertainties, the ages are intended as order-of-magnitude estimates. Furthermore, surfaces with no craters are aged with an upper limit given the resolution limitation (i.e. there could be smaller craters on an older surface). This gives a surface like SP an age of 30 – 50 m.y. despite modeling of the convection cells that suggests an age of ~500 k.y.. Other young terrains includes the E_TR and WM with estimated ages of ~250 m.y. and 1.5 G.y. respectively, but if some depressions are actually craters, like on WM, the age would be closer to 3 – 4 G.y.. The older surfaces are discussed more thoroughly in the crater frequency section. The heavy volatile processes in the north give it some of the youngest surfaces.

The bigger connection between terrain ages and geologic terrains is more complex. White et al. (2021) discuss the geology of Pluto (in this same book) discuss the geologic processes, and one of the oldest surfaces is assumed to be the north, despite the lower crater count. The intersection between these ages and the geologic processes is a larger conversation I hope to have as I study crater modification in my upcoming paper. This will look beyond crater count and study active modification of craters that are present.

Singer K. N., Greenstreet S., Schenk P. M., Robbins S. J., and Bray V. J. (2021) Impact craters on Pluto and Charon and terrain age estimates. In The Pluto System After New Horizons (S. A. Stern, J. M. Moore, W. M. Grundy, L. A. Young, and R. P. Binzel, eds.), pp. 121–145. Univ. of Arizona, Tucson, DOI: 10.2458/azu_uapress_9780816540945-ch007.

Early in my BookTube “career”, I posted 10 time travel book recommendations. These were basically my top 10 favorite time travel books. It quickly rose to be my biggest video, now at nearly 6k views, which is a lot for me! I’ve considered doing another list, especially since I cringe when I watch my self early on BookTube (at least less than I do now haha). Many of these books, I’ve reread several times, but most of them, I haven’t read in 3 or more years. I’ve wanted to reread many of them for a long time, but it’s hard to plan for such a thing when I’ve got nearly 500 unread books on my shelf to read. This month, I ended up moving apartments, and it has been the perfect opportunity just to throw on some fun reads. Now, having reread several of these on this list, I have a lot of thoughts, some really good some really bad. I thought it would be fun to discuss these books. I’ll be doing a video in the same vein, but for now, lets chat on here since I need a blog for my next meeting.

Lets start with the big ones. These are books I’ve reread at least once (maybe more) since this video posted because they remain all time favorites. When I am asked what my favorite books are, I always go to Kindred by Octavia E Butler and Middlegame by Seanan McGuire. Both of these are time travel (as are many of my favorite books of all time, and they’re favorites for good reason. I love the concept of time and the nature of time. I have an inherent thrill of time travel in general. This may have begun with the Magic Tree House series. That’s the earliest series I remember reading. However, the reason these two stand out are for how well each author uses the genre to tell a much greater story. Kindred is a story about a black woman, Dana, in her late 20s (present time, 1970s) who gets thrust back in time to the Antebellum south. In each visit, she finds herself interacting with this boy, Rofus, who is always in some dire situation. Once the situation passes, she gets thrust back forward in time. This cycle continues as we learn more about Dana’s relationship to Rofus, but it is also a stark reflection on slavery, bigotry, and privilege. It is so excellently used that it is hard not to become as enthralled as you are horrified. Middlegame is also dark, but it uses time travel for a different purpose. It is instead purely a speculative exploration of the genre, with an intersect of fantasy and science fiction. Roger and Doger are twins, made by alchemist trying to harness some great power. The story follows them in their childhood, as they are separated, and their inevitable finding of one another. That familiar sibling connection really strikes a cord for me, but more than that, the story is told in a somewhat nonlinear fashion, as Roger and Doger can manipulate time, but these abilities of theirs are not well understood. The story we are following is but one, not in a multiversal type way, but in a cyclical way. They are approaching the end of the world, and they are the cause. This is a lot of info, but I think it is a fairly reasonable synopsis (after all we start at the end, them near death in Timeline XYZ). It is the human connection coupled with the complexity of the story that makes this story work so damn well for me. Another work I enjoy, is Beneath the Sugar Sky also by Seanan McGuire. This is an example of a nonsensical story that subverts the usual need for a logical framework with time travel, and instead we have a nonsense world (quite literally a fantastical world ruled by nonsecial laws of nature). It’s not an all time favorite, but its the perfect example of a unique time travel story.

Similar to Kindred and Middlegame, I have a great love for 11/22/63 by Stephen King. This is a story about going back in time to save JFK. The concept is intriguing, but at the core, it’s King’s ability to write a compelling story with characters you can’t help but love, that keeps me coming back. This book is ungodly long. It meanders in directions that are unnecessary for the plot. It suffers from the diarrhea of the mouth that is so common for King, yet I’ve read it 5 or 6 times. It’s like an amusement park ride that never disappoints. It has the feel of classic Stephen King with a bit more modern perspective that can lead to the more problematic portions of his older works.

Now, moving on to my more recent rereads. I’ll start with the good, and save the really bad for last. I reread Glory O’Brien’s History of the Future by A.S. King. This is a young adult book about a young girl and her friend who eat a dead, petrified, bat that somehow gives them the ability to look into the eyes of people and see their past and future (including that of ancestors and descendents). At it’s core, this book is about growing up, mental health, and understanding one’s self. The time travel (if you count that, clearly I do) is merely a method to explore these ideas. It takes it a step further by analyzing all of our futures. In doing so, it becomes a dystopia as we enter a world where women’s rights have been stripped away, and the US falls into a civil war. When I first read this (2 years ago to the month), it seemed like scary but reasonable reflection on the direction of the US. Now, nearly a year since the insurrection at the capital, and the supreme court actively discussing and taking seriously the possibility to overturning Roe v Wade, the book is pretty damn prescient (and it was written in 2014). It retains its young adult feel, but the ideas are fundamentally real and terrifyingly easy to imagine.

Up next, I reread The First Fifteen Lives of Harry August by Claire North. This is a book I read nearly three years ago and absolutely loved. In the years since, I’ve seriously contemplated that it might be a favorite of all time (beyond my time travel list), but I’ve been slow to mark it as such because of how long it had been since I read it. Upon returning to it, I think it earns a position in my top 10 books. My love of this book is similar to Middlegame; that is, I appreciate the intricacy that went into it. The story follows the lives of Harry August except Harry does not live just one life, he repeats it. His entire life is a ground hogs day narrative. The first half starts with him, and us as readers, reflecting on what this is like, and I really appreciated the way North goes about this. I read this after rereading (for maybe the 3rd time) another ground hog day book that I will discuss, and it really outshines it. First off, it tales his life in a semi-nonlinear fashion. We follow him across his 15 lives, but he isn’t afraid to venture off in his story when another part of his lives is relevant to the situation being discussed. At about half way, we finally begin to realize the bigger picture, how this story, and the foreshadowing within it, is coming together. The end of the world is upon us, and it is happening sooner in every life. The ultimate cause relates to scientific progress and the ambition of one (or multiple) individuals. Overall, it has intriguing concepts with complex characters and plot.

Finally, there are four books I want to discuss together here: 1) Replay by Ken Grimwood, 2) The End of Eternity by Isaac Asimov, 3) The Accidental Time Machine by Joe Haldeman and 4) Somewhere in Time by Richard Matheson. Now we enter the territory of very sexist books. It was these books that motivated me to revisit this list of books. These books really shouldn’t have been on my recommendation lists, or at least they ought to have had a deeper discussion of the problems within them. Replay was, I think, my most recent read (last reread in 2018). This was my third reread, and I approached this read intentionally considering more than the plot, but the overall characterization, especially of women. This book was written, by a man, in the 1980s. It is often credited as inventing (or being one of the earliest uses of) the ground hog day narrative (even preceding the Bill Murray film). A man in his 40s dies, and wakes up in his ~18 year old self. The book explores similar themes to that of North’s book, but it does so lazily and without real depth. For instance, his younger self is attending Emory University in Atlanta, in the early 1960s, but we see no discussion of race. Naturally, he uses his youth to find women to sleep with. During his reliving, our main character encounters a woman experiencing the same thing. She is her own person, but I still don’t love her characterization as it still feels like it is written by a man. They spark a relationship, because, naturally, if a woman shows up in a mans story she most be there to be his love interest. There are other problems as well. She wakes up in her 14 year old self. At one point, they reunite in their younger selves and he makes a comment about how he likes the idea of her younger body. She responds with “I bet you do.” It’s disgusting in its own right, the sexualization of this child, even if she is mentally mature, but what woman would casually and amusingly accept that kind of statement? There are also larger problems with the sex he has that isn’t really explored. This man has lived decades, and more as time goes on, and he uses that to sleep with young women. There is a power dynamic there that just doesn’t work. It reminds me of the problematic power dynamic in the Time Travelers Wife.

The Accidental Time Machine was obsessed with sex in a different way, but it manages to touch on all the same problematic aspects. This is essentially a carbon copy of the Time Machine by H.G. Wells as a grad student at MIT makes a machine that goes forward in time. At the core, it’s a cool concept. It is an easy fun read. More broadly, it suffers in many ways. While it explores the future, the ideas feel hollow. He creates worlds that seem plausible, but I don’t feel like he does enough to have a compelling conversation. I’m instead left bored quickly by each period. Then we have the problem of women, where every woman is described by her sexiness and appearance. There comes a point in the far future where our protagonist takes on a time traveling companion. She is a young uneducated ultra religiously raised woman, and she’s introduced as his “grad student” (as he was granted professorship for his time travel machine long ago). In reality, she is an assistant. There is an attempt in all these to critique religion and the patriarchy, but it is extraordinarily shallow. Inevitably, our protagonist sees this woman sexually, but he, in all his nice guyness dares not make a move as he would be taking advantage of her. Of course, he is inevitably awarded for his good nature as he and her “fall in love”, which is ridiculous in its own right. It also side steps the power dynamic problems that exist between them, and the fact that they are not simply resolved, they’re just no longer a problem for him. He also fixates on her age, 18. Of course, the book feels the need to justify his attraction, because, after all, the legal age of consent is 18 in his time. This was yet another shallow attempt at him being a progressive good guy, but never do is there a substantive thought or discussion as to the purpose of the legal age of consent, treating it as if its purely a legal matter and no other reason that it would be wrong. This book is so bad, I cringe at how none of this stuck out to me the first time I read this. I am embarrassed for myself.

Moving onto the End of Eternity. This was something I rated 5 stars when I read it some 4 years ago, but I come to it with a different perspective now. Asimov has written a very well constructed time travel story. The basic premise is very similar to Loki with its time variant authority. I suspect the TVA was very inspired by this book. Overall, the main story itself is structured really well (once you get past the characters base motivation). It was creative and thought-provoking. I suppose we should expect that of Asimov. What I didn’t realize the first time I read this was that Asimov’s signature sexism is very much apparent in the story. From the get-go, this time travel authority who controls the timeline are all strictly men. Asimov makes an excuse for why women can’t be present, and in a way it almost feels as if he’s trying to imply they were something unique and superior about them that makes them too necessary to reality not to be removed from the timeline (where all the people in the “TVA” originate). But at the same time, it all feels very condescending in “a woman belongs in the kitchen” type of way. The only real female character in this book only really exists as a motivator for our main character. Our main character who is unbelievably insufferable. How the hell did I not catch this the first time around? The guy is horrible. He is so fucking self involved. It’s clear that Asimov intended it to an extent, but I wonder if he’s even worse than Asimov intended. Soon after he meets a woman, he falls in love, but before then he has a series of microaggressions against her because she dares to tempt him. The sexism at first seems almost intentional on the part of Asimov, but it quickly turns into something that I quasi-respectful or honorable when all it really does is put women on a pedestal and create a character who is entirely one dimensional. Every time we see this character she’s described by her looks, as an object, as something to be admired. She’s constantly referred to as *his woman*, as to be *his* and *not someone else’s*. It’s always a matter of who will win her and who will take her. It’s made all the worst but the fact that she’s not given any real personality. There is a moment (I suppose) towards the end where she has the slightest bit of characterization but not really. It’s shoehorned in and not well constructed. This book could have been so amazing if Asimov hadn’t let his own sexist ideas prevent him from realizing the fact that he had to build this relationship and the woman within it. It’s this woman, and the supposed relationship between her and our main character, that is quintessential to the entire storyline. And because that love story is sexist, forced and just out of nowhere it undermines the entire story. So when I could be here talking about how creative and the narrative this is, I’m instead left complaining about the fundamental problem of this book that keeps it from really being that great. At the end of the day, Asimov was very progressive for his time, but he was still very backwards and his literature clearly suffers because of it. I’m not saying it’s not worth reading, but the problems seem pretty glaring. 

Lastly, Somewhere in Time is not worth reading. I read this four years ago, and at the time I liked it, but it was my least favorite of these. Picture this: a man in his late 30s, whose never been romantic (emotionally or sexually), sees this woman on tinder and becomes so enamored that he stalks her Facebook, Instagram linked in. Anything he can find, he hunts her down. This alone is creepy stalker territory, all inspired by that tinder picture of her. Of course, it’s all okay because it was clearly meant to be. Now, when he finds this woman (lying to get close to her), every part of him gets the impression this woman is extremely uncomfortable. But he persists. Beyond all odds, she does not reject him because of some magical feeling that they were meant to be. Now add in time travel for them to meet and you’ve got this book. Except, instead of tinder, it’s a painting. And instead of social media is the library. Naturally, their connection must be fated or the author will have to acknowledge the utterly problematic basis to his story. I wish it was as simple as the motivation being why they meet, but the creep factor just never goes away. It’s constantly a battle of him doing what it takes to convince her, her comfort with a situation be damned. The fact that she so cavalierly accepts everything doesn’t negate the problematic underpinnings. What I will say, is that she feels more real than any of the women in older time travel stories I’ve been rereading. At least, she’s as real as the main protagonist is, which isn’t much. She has her own career and what little we learn about her revolves around it, but at the core of each other’s beings is their relationship to one another.

Big picture, I can see my reading has changed. I think I owe booktube for that, specifically booktubers like ONYX Pages who stress the importance of intentional reading. These kinds of reflective readings are things I am more consciousness about which is obvious by how my feelings have changed in just a couple years (in some cases).

My work is done using the Slush Fund 2.0 Mushy Layer Model of Buffo et al (2020; 2018). The code is designed in MATAB to solve a series of differential equations. My job involves adjusting the preexisting constants for the conditions by which I am studying. Then there are chemistry specific variables I have to change for each type of chemistry I solve (e.g. HCN). Then, I have to run the model for a series of initial conditions to get a full picture of what I am working with. The trick is recognizing that the model itself does not give exactly the information I need, so I have to devise an approach where I can easily use these results to produce the final product I am looking for. The SF2 model gives a 1D profile of how much an impurity will freeze into ice, if that ice formed in an infinite ocean. I want how much impurity would freeze into ice in a closed 2D system where you have ice freezing from the top and bottom.

However, I can I import these results into the 2D heat transfer python model of Chivers et al (2021) where I use a series of profiles that can be correlated to specific conditions to predict what a 2D system would look like. Like the SF2 model, this is easily done by incorporating the chemical and physical properties into the code for the scenario(s) I am studying. This is a bit trickier because I am not nearly as familiar with python as I am in MATLAB. I have worked in MATLAB for years, and even after “learning” MATLAB, I had to force myself into using it for everyday tasks to get really familiar with it. This means I have to ask for a lot more help when working with Python. What’s more, when I finally get the 2D result I’m looking for, I import the results back into MATLAB where I can more easily produce the final figures using these results. I essentially have a 2D matrix of impurity concentration for each position in the melt pond. I can easily plot this, but there are a number of other ways these results can be visualized to quantify and convey what the system looks like. For full details, see Hedgepeth et al (2021, in revision; DPS 2020).

Python and MATLAB are very similar in what they do. However, Python is free and MATLAB is not. They each are basically fancy calculators that are capable of solving a series of problems through a number of approaches. They may be capable of doing more, but this is all I am familiar with. The way they do it are slightly different, largely in syntax (i.e. how you type out the code), but they are very similar. They are overwhelming in their capabilities, but they offer a great deal of customization in how problems can be solved. What’s more, a well devised code can be multipurpose, allowing others to build on the work you’ve done.

I decided to take the geophysics field school because I realized I needed a Geophysics classified course. At some point, I knew this, but that fact was lost to me in my last 5 years here at Western. I think it was the fact that in my Masters, the required seminar took care of that requirement, paving the way for me to take planetary courses for the rest of the program. Enter the PhD program, and I don’t have that course since I took it in my masters. In my opinion, the planetary field courses should count in geology and geophysics; I suppose we could debate which classes fit into which program more. Nevertheless, the notion that physics based planetary processes (a course Dr Catherine Neish is teaching in Winter 2022) isn’t geophysics is absurd to me. There multiple courses about the physics of the earth, and what is planetary processes if not geophysics of other planets? Sadly, our Earth Science department hasn’t put much effort in really asking what each of their programs are meant to offer.

In any case, that left me in need of a course. I am in my final year, so my options of courses are slowly fading. I ended up choosing this course because it was short and I absolutely love the prof, Dr. Sheri Molnar. Still, this course came at a rough time. I had so much going on at once, and it wasn’t even my fault. A series of events just cascaded to put me in a rough August and September. I just wasn’t in the mindset for it. What’s more, I was very much resenting having to take it. All that said, it was generally a very positive experience.

This was my first actual class with Dr. Molnar, and I liked how she taught overall, but I have a couple criticism about the overall structure of the course. It was a bit much getting so much so early so fast. That is the nature of short courses though. After taking the oral exam, I feel we are expected to know a lot more than can be retained in such a short period. Then again, this course isn’t new, so it seems unlikely this method hasn’t been tested with a larger sample size than just me. I ended up struggling most with the actual field method, or in particular, the instruments. Multiple times, I left lecture immensely annoyed and frustrated at how esoteric it all felt. However, the hands on application that followed gave me what I needed to understand the method.

Part of me wishes we started hands on and then learned the theory behind it. Or, more realistically, start with the theory, learn how to use the theory in a hands on instrument application, then follow up the hands on with the explanation of how we relate its readings with the overarching theory. Instead, we learn the theory, how the instrument works, and how to interpret the readings of the instrument, then apply it. Logically, that seems to make sense, but I think we are more likely to retain the relationship between its results and the underlying theory after we understand how to use the instrument to get the results.

Now, I want to discuss the esoteric nature of these instruments to me as a planetary scientist. The methods really are outside my purview, and I think the focus does center around the departments ideas of what geophysics is. Then again, it’s by definition field work, not remote sensing or rover type work. That is part of why I was so resentful to take this course. It isn’t that it wouldn’t be good to know, merely that my time seemed better spent on other things. That said, in the end I am glad I did it. Its not as if this isn’t good skills to have. It absolutely is. The entire time, I was trying to think about how these techniques can intersect in a planetary mission type scenario.

The course itself, while not very focused on my area of interest, was an excellent way to learn and improve project planning and implementation. The most exciting part of this course was the ability to think about how we can apply what we learned to solve a given problem. That is relevant to any field, but I think it is especially relevant to planetary science considering any substantial science we do has to be thoroughly planned and vetted. What’s more, it allowed for a level of creativity that was remarkably satisfying to apply.

Don’t get me wrong, the class is a lot of work. There are times when I absolutely hated all the energy it was taking from me, in the classroom, the lab, and in the field. But at the end of the day, it was a very positive experience, not just because it was fun, but because I am now moderately skilled at several of these techniques. These are things that I generally enjoyed learning and applying, even if the thought of doing it wasn’t always positive.

First off, I’ve talked about time before. What I am not sure about is whether I’ve presented this to my lab before. Sorry Catherine if I have. After 5 years, I think I’m starting to recycle old ideas! I choose to talk about time because I’m busy, and time is a conversation that just comes naturally to me. Plus, we have so many new students, and I want to share this lovely idea with all of them.

Special Relativity

I imagine most of my readers (or if I’m presenting this, listeners) are familiar with Einstein’s special relativity. The faster you go, the slower time ticks. One of my favorite ways visualizing this is by imagining you plot your movement through time (y axis) and space (x axis). The magnitude of your vector in space time is fixed; as you move through space, you rotate that vector away from time. Similarly, large gravitational sources also slow time. If you’ve seen the pretty good movie, Interstellar, then I imagine you know this idea. It was one of the biggest challenges to my concept of reality as a kid; grew up young earth creationist. It doesn’t disprove a god, but this was really when I began to see how mundane my early ideas were. The nature of reality is so much grander than we imagine.

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The Block Universe

Around the same time I learned about Special Relativity, I learned about the concept of the block universe. Sadly, I went about a decade before I really understood the concept. I loved the idea, but my confusion around it led to me doubting whether my idea of it was ever right. Which is what motivated me to return to time. I read Lee Smolin’s Time Reborn, then From Eternity to Here by Sean Carroll, then The Fabric of the Cosmos by Brian Greene. Interestingly enough, it was the PBS special for Brian Greene’s book that really got me hooked to all this.

The basic idea (or question) is whether the Universe is a all moments (past, present, future) or just the current one. We have this idea that the universe is one moment in time, but special relativity suggests that is not the case. The notion of now falls apart in relativity. Because of how time changes, your “now” becomes deformed. I recommend watching the video below to get this best. The basic idea is is that the universe can be thought of as a block, or a slice of bread, or a book of pages. We think of books or bread, as sliced in equal parts, but that loaf, that block of paper that is the universe is constantly sliced differently depending on the observer. This introduces the idea of the Block Universe.

(3:15-5:00 for precise point) Brian Greene from PBS special on fabric of the cosmos.

While I am not an expert, I don’t think I’m wrong in saying that the block universe is fairly well agreed to be the most reasonable way of thinking about the universe. However, it is somewhat philosophical, and so there is dissent. Lee Smolin, for example, insists on Presentism, the idea that that moments come into existence, and the past no longer exists. I need to reread his book (but I don’t want to 😦 ) because it was not effective. I found no reasonable arguments beyond. He made a lot of emotional based arguments which is ridiculous. Nevertheless, I think I have a better idea of it all now and would like to explore his dissent again.

The Flow of Time in a Block Universe

This raises a question? Why do we remember the past but not the future? Let me start by recommending you check out PBS Spacetime which is a fantastic resource (see videos and playlists linked), and you can check out Sean Carroll’s book too which is where I first learned about this concept. I was confused at first, but I think I understand it enough to explain it? The quintessential idea is Entropy. Fundamentally, we know the past is constrained to a fundamentally less complex configuration while the future has the potential for a range of results. It’s not like we can’t postulate reasonably about the future, but the lack of information constraining it makes it difficult. PBS Spacetime does a good job exploring this concept. Fundamentally, the past leaves imprints, or records, that give us the ability to constrain the past. Whether it be geologic history or the various imprints in our mind. Honestly, it’s best to just watch the video to get the full idea, but for now, just entertain me.

The concept of Entropy introduces an interesting concept because it suggests the flow of time exists only because an entropy gradient exists. There is a much larger conversation to be had here about the history of the Universe because we have this idea of the origin of the universe being the origin of everything, but it is really just the origin of the universe as we know it. Sean Carroll explores this idea significantly with an entire chapter in his book dedicated to entropy. It reframes the idea of the origin of the universe from how it came to be to what triggered the high entropy state. I haven’t explored the idea recently enough to talk about it, but if you are intrigued by the concept, I recommend checking out these videos and Carroll’s book.

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For more cool PBS Space Time videos, check out this playlist I made (or their channel).