Mass Effect Astrographics (Part II)

This is the third of a series of five (Introduction, I, II, III, IV) posts about the astrography of the Mass Effect galaxy.

This specific post covers the systems and planets present in the second Mass Effect game, Mass Effect 2.

The Normandy Reborn

To say Mass Effect 2 (2010) is an improvement over its predecessor would be a vast understatement. It is to be expected that sequels might have improved graphics and, with a successful franchise, probably better mastered audio. With some luck, you might even get some gameplay improvements perhaps, too. What is much less common however is for a sequel's story and characterisation to vastly outshine its predecessor's. Mass Effect 2, against all odds, manages this in stride, and is widely regarded – with good reason! – as the best entry in the Trilogy.

Mass Effect the First had us in the shoes of Commander Shepard, recently made into a Spectre, one of the most notorious positions in Citadel Space, and interacting on the regular with the big wigs of the Citadel as well as different Megacorporations and larger-than-life techno-cephalopoidal eldritch abominations (as one does). Mass Effect 2 flips this on its head by driving Shepard underground, forced to interact with the shadier elements of the galaxy as they and their crew navigate its criminal underbelly, all under the ever-present gaze of Cerberus, the shady human supremacist corporation/group/entity/cult introduced in one of the first game's sidequests.

Mass Effect the Second is very much a more mature game than the first, eschewing a bit of its squeaky clean (but by no means morally pure, in the slightest) ascetic aesthetic and leaning hard into 'DARKER AND EDGIER!!1!' aspects – sometimes, I feel, to its own detriment. When it works, it really works, but there are times where I feel it veers into it not because it is interesting for the narrative to do so, but because it was a mandate from corporate. But I digress.

Mass Effect 2 brings back a lot of fan favourites – Joker, Tali, Garrus – and introduces us to many new faces that would themselves win over our hearts. The gorgeous Normandy SR-2, the eccentric charm of Dr. Mordin Solus, a genuinely cool guy who is rather unfortunately eminently puncheable due to looking exactly like Kanye West... but what truly matters for us here is that this game introduces us to a new, revamped galaxy map! This time, instead of just selecting where we want to go with a cursor, we get to fly a teeny tiny Normandy across the map! Now ain't that just swell?

Furthermore, the planetary information boxes now regularly feature the 'Orbital Distance' at which planets orbit their stars, unlike its predecessor! This makes it possible to calculate the stellar mass for all systems in the game... in theory (ooOOOoooOOoooh, foreshaaaadowing!).

Beyond that, I've also noticed a few interesting differences in trends when it comes to planets in Mass Effect 2 compared to 1; for starters, the inclusion of a few Hot Jupiters in the planet pool – which is only natural, as at the time the game was made they had come to the forefront of the exoplanetology world as many early exoplanet detections were of this type, due to observational biases favouring large, close-in worlds over smaller terrestrial worlds farther out from their star.

Another thing I noticed is a shift away from the remarks on planetary composition I mentioned in the previous post. In fact, whereas the entries in the first game felt like the work of a single person, I get the impression that this time around more than one individual might have been responsible for writing the planet entries, as the Vibes™ (a very scientific and quantifiable measure, I assure you) between some of the new ones do seem quite different. And I have to say, rather unfortunately, that the disconnect between Codex and gameplay has wormed its way into the planetary descriptions too this time around, as we will see...

A Rude Awakening 

One of the things that most jumped out to me after compiling all the data, and a big part of why I took so long to write this post, is that a surprising number of planets in Mass Effect 2 have ludicrously high density values – take for example the world of Partholon, in the Balor system on the Caleston Rift; it has a density of a whopping 19.42 g/cm³. That's nearly as dense as the densest element in the periodic table, Osmium, which comes up to 22.59 g/cm³!

This is highly unusual, to say the least. Rocky planets are composed of varying fractions of silicates and iron, as they are vastly more abundant across the universe than elements of atomic numbers 27+ as well as the fact that they are not 'volatiles' – i.e.: they remain solid even under a quite significant degree of stellar bakeage, instead of evaporating/sublimating off into space – they are 'refractory,' as we call'em. Logic thus dictates, if you'll allow me the Spockism, that the mass of a rocky, terrestrial planet of a given radius should be bound at an upper limit by the density of iron, which comes up to no more than 7.87 g/cm³...

... except that's not entirely true. See, the funny thing thing about planets is that they're made out of a lot of stuff. Stuff on a planet, being subject to its gravity, has weight. And when you pile stuff on top of stuff, the aforementioned stuff does a stu(ff)pendous job of putting the stuff beneath it under lots of pressure. This means that the deeper you go into a planet, the greater the pressure and the greater the compression of the stuff the planet's made off – the stuff's being stuffed harder, if you will.

A consequence of this is that the materials that make up a planet might actually be compacted way more densely than when subject to Standard Temperature and Pressure* conditions. Take as an example Earth's core: it is believed to be made of an Iron-Nickel alloy at a roughly 9:1 ratio. As such, we might expect its density to be between Iron and Nickel's at 7.97 g/cm³, but no! Because it is being compressed by an entire freaking PLANET's worth of stuff, Earth's core has a density of around 12.9 g/cm³, ish.
 *ISO 5011, for the sticklers in the room

Modelling all of this computationally is possible using steady-state models (no, not that one, get outta here cosmologists!) of planetary interiors, which use the known physical properties of materials and differential equations to figure out the planet's interior temperature and pressure profiles, and how all its constituent stuff will settle down without further collapsing in on itself. In fact, a freely available one anyone can use is ExoPlex, available on GitHub!

So because so many planets in Mass Effect 2 had densities higher than I felt plausible, I decided to learn how to use ExoPlex to try and test their plausibility. That's all swell GAB, but uh, slight problem: you're pursuing a degree, working, and getting embroiled in Random Assorted Shenanigans™ with an alarming regularity. How, exactly, do you wish to find the time to learn how to use a whole new tool for a blog post, you obtuse nincompoop?

Why, you've raised an excellent point, voices in my head. And indeed, I've completely given up on it in the name of getting this post done with. Hooray! So instead of using ExoPlex myself, I've turned to good ol' Universe Sandbox instead, which a few updates back has actually implemented exactly this, the simulation of planetary interior pressure/temperature curves and the usage of that information to drive planetary bulk density. I will also be referring to this paper by Unterborn et al. (2023) which actually introduced ExoPlex, as a way to sidestep learning how to use it myself and instead relying on work done by people smarter than me.

New Worlds                   

Mass Effect 2 features the following 23 individual Clusters:

1. Caleston Rift — 5 Systems
2. Crescent Nebula — 4 Systems
3. Eagle Nebula — 5 Systems
4. Far Rim — 2 Systems
5. Hades Nexus — 4 Systems
6. Hawking Eta† — 5 Systems
7. Hourglass Nebula — 4 Systems
8. Ismar Frontier — 3 Systems
9. Krogan DMZ — 3 Systems
10. Local Cluster† — 1 System
11. Minos Wasteland — 2 Systems
12. Nubian Expanse — 3 Systems
13. Omega Nebula — 6 Systems
14. Pylos Nebula — 4 Systems
15. Rosetta Nebula — 3 Systems
16. Serpent Nebula† — 2 Systems
17. Shadows Sea — 1 System
18. Sigurd's Cradle — 2 Systems
19. The Phoenix Massing — 5 Systems
20. The Shrike Abyssal — 2 Systems
21. Titan Nebula — 1 System
22. Vallhallan Threshold — 3 Systems
23. Viper Nebula — 1 System 

Totalling up to 71 individual star systems. Clusters marked with † have previously appeared in Mass Effect.

Much like in the first game, which featured the real Horsehead [sic] Nebula (Barnard 33) as one of its clusters, Mass Effect 2 has quite a few real locations among its roster: the Crescent Nebula (NGC 6888), the Eagle Nebula (M16), the Hourglass Nebula (MyCn18)†, and somewhat surprisingly, given its rather 'extra' name, the Omega Nebula (M17).
†There is another 'Hourglass Nebula' within the Lagoon Nebula, but the one showcased in ME2 is MyCn18, a picture of which is used as the cluster's background art.

Also possibly real is the 'Rosetta Nebula' – there is actually a Rosette Nebula (Caldwell 49), but single-letter difference aside, as the Mass Effect wiki itself notes the cluster's in-game art seems to be using a flipped image of the Orion Nebula instead. I will have quite a few things to say about this cluster still...

As previously mentioned, this time around we've actually had the planets' orbital radii as a rule rather than the exception, which allows us to have a cursory understanding of each system's central star. A fun fact about Kepler's Third Law of Planetary Motion? If you use as units Earth's orbital radius and orbital period (i.e.: AU and Sidereal Year), the resulting Keplerian constant is spat out as the multiple of the Sun's mass required for that radius-period relationship to hold – i.e.: for all intents and purposes, Solar Mass (M⨀). This means that by calculating the Keplerian ratios of the different planets (with error margins) we can find out the parent star's mass!

Spoiler: it's a mess. For one, there are a few systems where different planets will have completely different Keplerian ratios, which should not be possible. Minute variations? Yeah, sure, that happens because the planet's own mass should technically be factored in as well when running the calculation, but it's a whole other thing entirely to have one planet orbiting around a star of 0.3 M⨀ and the other 1.7 M⨀. Furthermore, I've found that pretty much every single system where the star is of a given spectral type seems to have the exact same mass.

Am I completely sure about the above? Admittedly, no. The error margins on the calculated Keplerian ratios don't allow us to beat the gavel and make a ruling on it, but, like... consider the Aysur system, in the Caleston Rift. It has six planets, and the Keplerian ratio with the smallest relative uncertainty is that for the outermost planet, Tamgauta: (0.99302±0.00355) AU³/Yr². Hm.

Consider, too, the Relic system, Eagle Nebula; lowest relative uncertainty? Beach Thunder, (0.99339±0.00455)AU³/Yr². Hmmmmmm.

What's more, for every planet in these two systems? The value 1 is safely within the error margin for every single one of its planets' Keplerian ratios. This also holds true for other systems, and for different mass values too. It seems to me that, when cooking up the different systems for Mass Effect 2, whomever was responsible always used the same mass value for a given star type. As far as I've been able to divine, the values used seem to be: 0.3 M⨀ for M-type stars; 0.8 M⨀ for K-type stars; 1.0 M⨀ for G-type stars (which make up the vast majority of the game's systems); 1.7 M⨀ for F-type stars.

Three stars are noteworthy for breaking this mould: Nith (Krogan DMZ), stated in-game to be a B-type star in the description of its planet Mantun, has a most likely mass of about 14.87 M⨀; Dirada (Pylos Nebula) has a most likely mass of 3.17 M⨀, which assuming it to be a main sequence star, would also make it a B-type. And finally, we have Qertassi in the Nubian Expanse, sitting at an utterly chonkular 40.8 solar masses as derived from the Keplerian ratio of its single planet, Norehsa, in the description of which the game remarks the star to be “an elderly, metal-poor Population II star, broadly similar to Arcturus.” Even though Arcturus is thought to have a mass similar to the Sun's, but hey, I digress.

Finding out that the same star classes seem to have the exact same masses was a bit of a letdown to me, I do have to admit, but on the flip side this regularity opens up the possibility of our examining planetary properties that we would not have been able otherwise; namely planetary temperatures, as we'll be able to make reasonably good guesses on stellar luminosity and from that we can calculate blackbody equilibrium temperatures, infer the different planets' albedo values, and even possibly their atmospheric greenhouse effect values too, though this all vastly exceeds the scope of today's post.

And finally addressing that whole planetary density thing I alluded to at the start of the post; Partholon, the worst offender in the game, has a mass of (23.07660±0.17483) M⨁ and a calculated density of (19.42125±0.14713) g/cm³. This is the Balor system's (Caleston Rift) outermost planet, far beyond the system's frost line. As such, considering its sheer mass, it's borderline unthinkable that this planet is somehow terrestrial – it has exceeded by far what is necessary to start slurping up Helium and Hydrogen from the surrounding proto-planetary nebula and grow into a gas giant via core accretion, as goes our modern understanding of planetary formation, and yet in-game its atmosphere is simply given as 'trace'.

Be that as it may, in using Universe Sandbox to try and figure out what sort of physical composition would be required to get this sort of bulk density, I was somewhat surprised to find that it is, in fact, physically possible through the magic of gravitational compression. It would require, however, that the planet have a frankly ludicrous 75:25 Fe:Si ratio, or in other words, the planet'd have to be three quarters pure iron. This is... very unlikely, to say the least – doubly so when considering just where in the system the planet is. I'd love to cross-reference this value with Unterborn's paper too, but the planet's mass is such a ludicrously high value that Unterborn doesn't have such high-mass planets listed in his tables as possible 'terrestrial' planets, so...

The End Run

Before we wrap up this post, I must first remark on two other things that jumped to me while compiling all this data, the first being the codex-gameplay disconnect I alluded to earlier in the post.

I've always been rather chagrined by the fact Mass Effect, as a franchise, seems to largely ignore the Codex except when convenient. In many ways, Mass Effect as presented in the games feels like a poor Netflix adaptation of an excellent sci-fi novel which would have been its Codex, keeping the same recognisable shape but feeling rather... pasteurised for general audiences, and it pains me a bit.

What is particularly annoying though is that this disconnect between gameplay and the games' written material now seems to extend to the planetary descriptions too; the planets Sinmara (Solveig system, Caleston Rift), Taitus (Talava system, Caleston Rift), Haestrom (Dholen system, Far Rim), and especially Gei Hinnom (Sheol system, Hades Nexus) are all listed as having 'trace' atmospheres or a surface pressure of 0.0 atmospheres, and yet when going down to their surfaces they all clearly possess atmospheres. On Taitus and Haestrom both, your party struts around with no helmets nor respirators just fine. But worst of all is Gei Hinnom, which is supposed to be – and I goddamn quote – “A nearly atmosphere-less, tidally-locked planet orbiting a red dwarf star,” and yet has, I kid you not, an entire freaking JUNGLE down there!

I– Wha–...? ... C'mon guys, you're better than this... 

Another disconnect between description and what's actually on-screen is Helyme (Zelene system, Crescent Nebula), where “(...) a global extinction occurred, wiping out all native animal life forms more complex than zooplankton.” And yet, down on the surface we see them little roly-poly beetle-buggy fellas that crop up every now and again in Mass Effect's worlds, as well as bird-like critters flying at certain points of the map. Why, that sure is some darn weird zooplankton, huh?

But the thing that really, really rustled my jimmies – nay, outright crinkled my Jameses – is a single star system in the accursed cluster that is Rosetta Nebula (remember that? Told you we had unfinished business with it...). Not only is the cluster itself named sufficiently closely to a real nebula for us to be tempted to connect the two, to add insult to injury, one of its systems is named 'Alpha Draconis'.

'Well, so what, Gab?' So what, dear reader, is that Alpha Draconis is a real star, 'α Draconis' being the Bayer Designation of the star traditionally known as Thuban, in the constellation of Draco, the Dragon. Small problem: it's not anywhere near close to any nebulae, and everywhere too close for us to not know of any nebula near it, at a measly 303 light-years away from Earth, give or take a handful. What's more, neither of the two nebulae (Caldwell 49 & Sharpless 2-170) this stupid cluster could be mapped to are ANYWHERE close to Thuban in the night sky! At all!

If you're not going to bother even trying, WHY would you name a system after a real star!?? 

ₐₐₐₐₐₐₐₐaaaaaaaaaaaaaaaaAAAAAAAA̷̝͝Ȁ̴̰A̶̛̮À̶͜A̴̝͑A̶̙͂Ȁ̷̜A̸͇̤̣̱͛̆Ä̸̧̧͔́̊̌̽Á̵͜A̸͚̞̎̂A̸͔̒̅̏̓A̷͚̫̐̒A̶̡̢͔͈̒̆̏̚A̴͙̰͝Ạ̸͇͘A̸̲̠͑ͅA̶͚̼̠͋̃͑A̵͚̬͉͒A̶͖͚̲͕͋͐͘͝——

Why, sorry about that – I seem to have briefly lost my composure. I'm sure this little hitch won't be any trouble for us down the line when we try to map out the Mass Effect world unto the real Milky Way galaxy, haha, ha...

... ah, damn it. 

Reflections

With all that out of the way then, without further ado, here's the link to the compiled data for Mass Effect 2's star systems, all dully transcribed and noted down as per last time: https://docs.google.com/document/d/1vMPPk_9lLT05nuq0lXWV6OgP_Hj4FRHep8m6Hl6Jvlo/edit?usp=sharing

As of the time of posting, the Appendix section of the above doc has been transcribed directly from the first one's, and will thus see some small revisions to properly reflect this new document, as well as the inclusion of a few more formulae. That and one little last check to see if a typo was actually present in-game or I made a mistake is all that's needed before I can call this one truly well and done, and then move on to finish compiling the Mass Effect 3 document.

As per last time, comments are disabled on the document itself, but if you have any remarks, questions or comments, feel free to drop me a line down in the post's comments section!

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Well then. This uh, this took a while. I guess I now know better than say that the next instalment 'won't take too long,' huh?

I really do want to start posting more here on the blog, so you can actually expect some non-Mass Effect posts this time around, for reals this time, pinky-double-swear. What I know for sure is that I'll be starting a series of posts on using the amazing Traveller Map and interpreting its many, many fields of data in ways that are useful at the gaming table.

And, well, living up to the blog's motto, there'll probably be some Random Miscellanea™ along the way as well. Until then! 

Blog Update: 2024 in Review

 Hello, everyone! A quick update reassuring you that, no, I am not dead yet (I can dance and I can sing).

I had intended to publish the second part of my Mass Effect Astrographics series not long after the first, given the data was already compiled and all, but upon reviewing it to write a bit about the numbers, I realised the prevalence of a lot of really dense planets.

Like, really dense. Nearly Osmium-dense.

My area of 'expertise' (applying the term a bit liberally, but do indulge me) is orbital mechanics and planetary systems, which can touch upon but is different and separate to planetology itself, so I had to go reading. And hoo boy, is there stuff to read.

So while I'm still working on that, I thought it'd be interesting to do a bit of a retrospective on the year Twenty-Twenty-Fourtheth of the Common Era to justify my delays show you what I was up to, and as a way for me to keep tally of it all, as well (ever since the Pandemic time's gotten a wee bit murky).

In Sojourn Land:

This was a very busy year for The Sojourn. We released our most complex production yet, and finally got a side series that had been stuck in development hell off the ground, which was very gratifying.

• We produced and released the first volume of Season 2
• We produced and released the nearly two-hour long special, Faithless
• Started producing and releasing the youtube series The Frontier War, which we'd intended to do for YEARS and finally managed to get going.
• I've started to write more lore shorts for the youtube channel, something which I might do even more of this year – we'll see.

 Overall, a very busy year for us. 2023 might still hold the title for busiest year, maybe, but 2024 is certainly a strong contender for runner-up.

 In University Land:

University's been the same thing it has been for the last [REDACTED] years of my life, and my strongest desire in life is to grab my degree and run away from it as fast as humanly possible, but hey, it wasn't all bad! The highlight of the year was one of the classes I took, Evolution of Astronomical Thought, the closest thing we have in our curricular grid to Philosophy.

In it we have an overview of Epistemology, Gnosiology, and Ontology, followed by some exposure to the thoughts of Karl Popper, and Thomas Khun's The Structure of Scientific Revolutions. For those of you more well-versed in this area of knowledge, yes, this is all very basic, but it was very exciting and a welcome change of pace from the usual subjects I take. Philosophy of Science is something I could see myself coming back to in future.

And finally, I've been talking to my Academic Advisor (who also happens to be my Research Advisor), and I might resume doing research in 2025, to have some material to write my Course Conclusion Thesis about. Based on my skillset and his interests, this will most likely involve looking into tidal evolution of moons or exoplanets using REBOUND, but we'll see.

In TRAVELLER Land:

One of the most exciting things for me this year was that 2024 marked my entry into Traveller as more than just a fan, but an actual contributor. This year:

• The new Starship Operators' Manual was published with my contributions to the Gravitics and Jump Drive chapters (and a few scattered additional blurbs), and my first Traveller writing credit!
  
• My Flea Trader article got published on the new Journal of the Travellers' Aid Society, Volume 16, my very first to be accepted to JTAS
• Helped Geir Laneskog proof-read and test the new Vehicle Handbook Update manuscript and even contributed a few basic vehicles for the book
• Helped the Planet RPG folks here in Brazil translate Mongoose Traveller 2nd into Portuguese for the first time!
• Participated in a couple of podcast episodes with the Planet RPG folks talking about Traveller
  
• Got in touch with Marc W. Miller regarding an inconsistency I noticed in the Vilani Calendar, and with his approval and insight from Rob Eaglestone as well, was allowed to redesign it to try and fix/reconcile the inconsistencies. In fact, I'm writing them my final report on it this week!

Overall, very exciting for me, and I hope I can do even more things on this front in 2025. Fingers crossed!

In Blog Land:

And finally, but certainly not least, in 2024 I started my blog! This very thing you're reading right now!

Posts were a bit sparser than I had hoped but all things considered just getting it off the ground is, for me, something to celebrate. I have historically had the very nasty habit of planing things and never actually getting on to put them in motion, so I'm very pleased with myself that I got this ball rolling.

I'll do my best to be more active here this year. Lots of things darting 'round my head all the time and I do need some place to write them down, after all!

Now, if you'll excuse me, I need to figure out how to get ExoPlex running on my computer so I can write that second Mass Effect Atrography article...

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Happy Mayday, Travellers!

Today is a very special day — it is Mayday, the day which fans of the seminal Science Fiction Role-Playing Game in the Far Future, Traveller, have decided as the one to celebrate their beloved hobby.

To me however, this particular Mayday is doubly special, as it marks the release of Mongoose Publishing's newest book: the Starship Operator's Manual.

SOM is a reimagining of one of Traveller's most-beloved books, published way back when in the MegaTraveller days by Digest Group Publications†: the Starship Operator's Manual, Vol.I, which dived deep into the functioning of starships in the Charted Space setting; 'Charted Space' being the name of the Official Traveller Universe (OTU); sort of like what the Forgotten Realms are to D&D.

"Alright, that sounds cool, but what's the big deal about it, Gab?"

Why, the big deal is that I helped write it!

I was one of the four authors: lead author Adrian Tymes, co-author Sabrina Tymes, co-author Rob Eaglestone (who also helped pen Traveller5), and... I! This book has been a long time in the making; I got in touch with Adrian way back in August of 2022, after he'd asked in the Traveller fan server on Discord for people familiar with the original SOM who would be interested in helping write a new version of the book for Mongoose.

In many ways, my involvement with this project was a ridiculous confluence of luck leading me to be at the right place, at the right time, and in touch with the right people. And boy, am I thankful for that luck!

There's a lot I could say about the book itself, its writing process, our ideas for it; there's certainly no shortage of topics. But for now, I'll just say how proud I am of the work our writing team put into this, and how happy I am seeing the reactions of folks who've already bought the book.

A happy Mayday to all, and safe Travelling!

† Sadly, legal circumstances about ownership rights since Digest Group Publications folded mean that none of their products — which include not only some of the best, but most beloved products ever put out for Traveller — are unavailable for purchase in either physical or digital formats. The only way to get your hands on a copy of those DGP books is through the second-hand market.

Mass Effect Astrographics (Part I)

This is the first — well, technically the second — of a series of five (Introduction, I, II, III, IV) posts about the astrography of the Mass Effect galaxy.

This specific post covers the systems and planets present in the first Mass Effect game.

 

Spectre Induction

Mass Effect (2007) marks the very first time we're introduced to the Terminus Systems, the Attican Traverse, to Council and System Alliance Spaces. If you've played the Trilogy, you are more than likely at least passingly familiar with Mass Effect's version of the Milky Way. If you haven't, however, let's get you up to speed.

Mass Effect is set in the year 2183 with humanity being the newest kid in the galactic block, populated by the species that make up the Citadel Council — a two-and-a-half-thousand years old institution that is, for better or worse, basically Space UN. It is headquartered in a huge, O'Neill Cylinderesque station called the Citadel (gasp!) which predates all current spacefaring civilisations, all of which inevitably end up stumbling upon it sooner or later, as travel across the galaxy happens via use of Mass Relays — constructs which superluminally catapult starships to another receiving Relay, usually (but not always) forming pairs — and all Mass Relays lead to the Citadel.

The construction of the Citadel and Relay network alike are ascribed to an extinct spacefaring civilisation which seems to have at one point ranged most of the galaxy: the Protheans (why, what an original name for a precursor species! But I digress). In truth, the reality is not so simple and clear-cut, but if you haven't played the games I shan't spoil it for you.

Beyond the Relays, faster-than-light travel is also accomplished via use of the eponymous mass effect, a phenomenon which allows for the manipulation of apparent masses via Dark Energy Shenanigans™. Ships travelling under their own power, however, accumulate a static charge over time that, unless discharged at a suitable magnetosphere somewhere, will eventually vacuum arc and fry, kill, and toast (in more-or-less that order) any living thing and computer aboard the vessel. It is also notoriously slower than Relay travel; while no straightforward figure is given in the games themselves, from dialogue we can safely assume speeds on the order of ~10 Light-years/day.

As a natural consequence, space in Mass Effect ends up getting divided into clusters — star systems located around Mass Relays that can easily be reached from said Relay under a starship's own FTL motive power, which is how you navigate space in the games (most notably 2 and 3, where you actually get to fly a little SSV Normandy across the map instead of just selecting worlds). Instead of being correlated by physical proximity then, what truly matters is how the worlds are connected to one another via their associated Relays, forming what is essentially a node graph. Mathematicians in the crowd, rejoice.

The Secret Labs

Much like we do in Mass Effect('s opening cutscene), the best place to start this endeavour is in the Sol system. The reason for that is simple: we know what the real Solar System is like, and therefore have something to compare the information given in the system map to. Take, for instance, the entry for Earth:

Home sweet home...

This follows a very standard pattern for the entries of terrestrial worlds: the Description common to all non-stellar bodies and then social data for specific inhabited worlds, followed by orbital distance (more often than not omitted), orbital period, radius, day length, atmospheric pressure, surface temperature and curiously omitted in this case, surface gravity.

From this we can already gather some interesting information about how Mass Effect presents its planetary data: from the Radius entry, we learn that it is specifying the equatorial radius of the given body. Earth is not a perfect sphere, but rather an oblate spheroid, due to the centrifugal forces* caused by its rotation around its own axis. The result is that its polar radius is ~6356.752 km, its mean radius is ~6371 km, and its equatorial radius is ~6378.137 km, which matches closest to that presented in the entry.
* Inertial forces are still mathematically forces, grow up.

Similarly, we can see from the Day Length entry that it is referring to its Sidereal day, not its Solar day — a little known fact is that Earth does not take 24 hours to rotate around its own axis. No, that 24 hours period is how long it takes for the sun to reach its highest position in the sky between two different days; this is called the 'Solar Day', for obvious reasons. The Earth's rotation period is instead, 23 hours, 56 minutes and 4.1(-ish)† seconds (which comes out to ~23.9344 hours). The reason for this discrepancy is that, while the Earth is merrily spinning around itself, it is also rotating around the sun at a rate of roughly 0.985° every day, such that if you waited exactly 24 hours, the sun would not be in the same place in the sky as the moment you began counting. The Wikipedia page for Sidereal Period has illustrated explanations which might make this easier to follow, but the long and short of it is, the Day Length entries seem to indicate the planet's rotation period.
† This small variability is why leap seconds are a thing.

The last figure of particular interest is Surface Temperature. Mass Effect gives this as 23°C, but Earth's average surface temperature in real life is 15°C. The game is set in the year 2183 and global warming could have changed that figure, but with a warming of 8°C!? If that were the case, the ensuing ecological collapse would be noted somewhere. A more reasonable explanation is that instead of the Global Surface Temperature, the game is giving the average yearly temperature at the planet's tropics. The city of Campinas, for example, located 60 km from the Tropic of Capricorn, has an yearly average temperature of 22.4°C. Factor in a bit of global warming, and we have a potential match.

While finding a plausible explanation for the value is rewarding, I find the implications of it rather unsatisfactory — if we wish to use Surface Temperature to try and calculate other parameters, this tropics-reliant definition makes it so we need to know the planet's Axial Tilt to arrive at any meaningful figures, which is not a value Mass Effect gives us. This relegates 'Surface Temperature' entries to merely qualitative comparisons when assessing planets, instead of an useful property.

Alright then, we have an initial set of assumptions. How well do they hold in practice? Let us test them by having a look at Earth's little brother, good ol' Mars:

I actually have very strong feelings against Mars, but that's probably best saved for another post...

The listed Radius is 3402 km, which is actually a bit larger than Mars' actual equatorial radius of 3396.2 km, but given the mean and polar radii are both smaller than it, sure, let's go with that. The listed Orbital Period is 1.88 Earth Years, which matches almost exactly with the real one. Day Length is given as 24.6 hours, which is closer to Mars' Sidereal Day (24.62297 hours) than its Solar Day (24.66 hours), so again our assumption here holds. The Surface Temperature is listed as -138°C, which once again presents problems. According to wikipedia:

“Surface temperatures may reach a high of about 20 °C (293 K; 68 °F) at noon, at the equator, and a low of about −153 °C (120 K; −243 °F) at the poles.”

So it at least seems plausible that the median temperature at the tropics (which on Mars are at latitudes 25.19°N and 25.19°S) could be around -138°C, but I lack the data to confirm that.

Lastly, it gives us the Surface Gravity value as 0.38 G. Mars' surface gravity is 3.72 m/s², so checking the given Mass Effect value against it confirms that they're (probably) using the usual 9.81 m/s² for their definition of G.

And with that, we have a good grasp on what, exactly, these entries are telling us and therefore what we can and can't do with them! And just for completion's sake, here's Jupiter as a stand-in for the usual Gas Giant entry:

[Gustav Holst intensifies]

 

The Gas Giant entries lack a lot of the Terrestrials' data values for, well... self-evident reasons. As with those, most omit the Orbital Distance entry. The Radius given for Jupiter here is 71492 km, which matches that found by the 1 atm convention exactly — as Gas Giants don't really have a 'surface' per see, the adopted convention is to consider the altitude at which their atmospheres reach the same pressure as Earth's at its surface (1 atm) to be the Gas Giant's 'surface'.

Now that we have our bearings, we're ready to set out for the wider galaxy. Let us see what the universe is like beyond the Charon mass relay.

Uncharted Worlds

As previously explained, the Mass Effect galaxy map is divided into Clusters, each containing a few star systems each. Which clusters are present in each game actually vary, with only two being present across the entire trilogy: the Local Cluster (where the Solar System is), and the Serpent Nebula (where the Citadel is). Given it's unlikely a whole region of space stops existing, it's no stretch to assume that not all existing clusters are represented in the Galaxy map and navigable by you during the games. Considering many clusters in ME1 are not present in ME2 but return in ME3, I think we can take that as a given truth.

Anyhow, Mass Effect features 17 individual clusters — these are:

1. Argos Rho  —  3 Systems
2. Armstrong Nebula  —  5 Systems
3. Artemis Tau  —  4 Systems
4. Attican Beta  —  2 Systems
5. Exodus Cluster  —  2 Systems
6. Gemini Sigma  —  2 Systems
7. Hades Gamma  —  5 Systems
8. Hawking Eta  —  1 System
9. Horse Head Nebula  —  3 Systems
10. Kepler Verge  —  2 Systems
11. Local Cluster  —  1 System
12. Maroon Sea  —  3 Systems
13. Pangaea Expanse  —  1 System
14. Sentry Omega  —  1 System
15. Serpent Nebula  —  1 System
16. Styx Theta  —  2 Systems
17. Voyager Cluster  —  3 Systems

Totalling 41 individual star systems.

You might recognise one other name beyond Local Cluster — the game features the Horsehead [sic] Nebula (Barnard 33) as one of its clusters. This opens up some interesting venues of investigation when it comes to mapping out the Mass Effect galaxy onto the real Milky Way, but that's something I intend to do in the last post of this series. For now, it's but an interesting observation.

There are many curious things to note about the planet descriptions, but the one that really draws my attention is how often they point out not only the atmosphere's chemical composition, but the surface's as well — this is something I feel is frequently ignored by most science fiction.

While the overall elemental abundance of the universe as a whole is more-or-less-ish the same everywhere, different stars have different metallicities. To those not in the know, Astronomers class everything in the periodic table into three categories: Hydrogen, Helium, and everything with more protons than Helium is a 'metal'. If you're a chemist and have been driven to a paroxysm by this, as the kids nowadays would put it: "L + Ratio + Don't Care + Didn't Ask".

Anyhow, my point being: different stars have different metallicities, and even stars of a same metallicity will most likely show differences in their relative abundances of specific chemical elements, with those stars formed in a same stellar nursery being as chemically close to one another as you can get, but still not exactly identical. This is almost certain to have some interesting implications for the mineralogy of exoplanets. I mean, sure, the bulk of terrestrial planets everywhere will very likely have crusts made out of some silicate mineral, but will it necessarily be Olivine? Could there be a planet out there whose crust is primarily Andalusite and Kyanite?

I haven't read much in either fiction or academic literature about exomineralogy, but the latter might simply be due to how recent my own interest in geology is — I have yet to earn my Rock-Licker‡ stripes.
‡ (Said with love & respect for geologists)

In the context of the games, the different chemical abundances of planets mostly inform if there's commercial mining activity on their surfaces, with interstellar civilisation having a somewhat ravenous appetite for rare-earths and platinum group metals. If the planet is one of the ones you have surface missions on, it can also inform what deposits you might find, which is of interest to a specific sidequest, but I digress. 

Overall I think the terrestrial planets are quite believable in terms of their densities, all within a fairly reasonable 1.0 to 8.0 g/cm³ range (Earth's is 5.513 g/cm³), with a few notable exceptions that go upwards of 11.0 g/cm³, like Patatanlis in Han System/Gemini Sigma. I find it very hard to believe such a terrestrial world could be half as dense as Osmium. Its description does give enough margin for us to interpret it might be a Cthonian Planet, but even still... then again, planetology is not quite my area; my emphasis is on how they move, not what they're made of.

Speaking of how they move — planets' entries in Mass Effect are notoriously different from those in ME2 and 3 in that the overwhelming majority of them lack any information as to their orbital distance from their stars; they only list their orbital periods. Only 12 of those 41 systems contain a planet (or planets) with orbital distance information, and one of them is the Sol System.

The sample size is relatively small, but as I was calculating planetary keplerian ratios and the stellar masses, I got the distinct feeling that almost all systems with a habitable planet have a central star of 1 Solar Mass. As in, exactly 1. That's obviously not something I can definitely prove, of course, as the relative uncertainties in the keplerian ratios are too high, but... it fits too cleanly in those systems with multiple calculable keplerian ratios for me to ignore. Something that bears investigating in future games, for those systems that show up on ME2 or ME3.

Vigil

But finally, without further ado, what you're all here for: the collected system data from Mass Effect, all dutifully and carefully annotated and collated in one place.

I have done my very best to transcribe the information down as exactly as I could — there are many things I could have changed for better comprehension or to standardise things or even to correct obvious mistakes, but that wasn't my goal. Do not get me wrong, I very much intend to do a deep dive in this and fix and change things at some point, but this document is intended as a source, not a derivative work — a document people can refer to when doing their own subsequent projects. It, therefore, needed to be as close to the in-game info as I could make it.

I have taken care to make it very clear what was put down in the doc by myself and what is directly extracted from the games. All of my own additions and observations are clearly marked as such, and the Appendix goes in-depth on how the process of making the doc was, including the maths used to calculate the derived planetary parameters and their uncertainties.

It is also important to note that, as the information was transcribed verbatim from the map, certain information, especially that pertaining to the arrangement of Clusters and their connections, does not entirely match the in-game fiction. Consider: the Charon mass relay in the Solar System (Local Cluster) is said to lead to the Arcturus System and that system alone, and yet in-game the Local Cluster links directly to Exodus Cluster, skipping the Arcturus Stream altogether. I have made no attempt whatsoever to fix this — that's for Part IV of this series of posts!

The link to the Google Doc with the information is: https://docs.google.com/document/d/1VhH2mtYWwJSQbHWCcLkWUSTD2jhtumEpNuY40SZYZtg/edit?usp=sharing

Comments are disabled on the doc itself, but feel free to leave your own comments and thoughts down on this post!

⬢⬢⬢

And with all that done, the next post in this series shouldn't take too long, all things going well. All data for ME2 is already compiled, I just need to finish going through it and then format the doc for release, which should be very straight-forwards now that I've already figured it out for this first one.

There might be a few, non-Mass Effect posts on the Blog in between these two entries, but we'll see. In either case, until then!

Mass Effect Astrographics (Introduction)

This is the first on what I expect to be a series of five posts (Introduction, I, II, III, IV) about the astrography of the Mass Effect galaxy — which happens to be our galaxy, just with... a few differences, let's say.

This post will be an introduction of sorts, providing a bit of context as to why in blazes did I do this and, better yet, what the hell this even is. If you only care about the raw data, feel free to skip to the next post in this series. Whenever that comes out.

ME & Me

The first time I ever heard of Mass Effect was when I and one of my cousins spent a weekend at my grandmother's house in the countryside. I was never much of a consoles guy, but my cousin had an Xbox 360 and he brought it with him, along with a small selection of games he owned. 

Among those games was one called 'Mass Effect 3', some sort of sci-fi RPG-shooter game? I asked him about it, and he dismissively gave a shrug saying it was 'all right, I guess. Plays fine.' That night we played some of his other games for a bit, and when he decided to call it a day and head to bed, I asked if I could try out that 'Mass Effect' game. He said 'sure, play as much as you like'.

And then I proceeded to play it for eight hours straight, up to around four in the morning.

 I remember being impressed by the story, sure, but what really floored me and had me hooked was the setting. Of those eight hours, a solid four were spent just reading the different Codex entries and planet descriptions in the system maps. To my young self, they presented a degree of worldbuilding that I had never truly seen before — and what's more, it all felt so real! The applications of the eponymous mass effect felt like natural consequences of that sort of mass manipulation and the aliens, whilst somewhat human-like at times, all had their characteristics that made them feel alien.

After that weekend was over and my cousin and I went back to our respective homes, I was left distraught. I didn't own a console, I didn't have a PC at the time (most of my life I've had second-hand Macs from my parents), and thusly had no way of playing Mass Effect. I went to class that Monday, and talking to my friends during the break, I found out that one of my best friends, João (or 'John' for the Anglophones), was also a huge Mass Effect fan.

Over the following years he's invited me over so I could play the whole trilogy, from start to finish, as a continuous play through. In total, I must've spent upwards of 80 hours playing ME over at his place. I never did actually finish the whole play through, having stopped making some headway into ME3 — somewhat poetically around the same place I had back when I first played it at grandma's on my cousin's Xbox. Quoth Lucas, 'it rhymes'.

Someone Else Did Get It Wrong

Mass Effect Codex, my beloved

In the intervening years, quite a bit has changed. I still love Mass Effect, don't get me wrong, but time and exposure to other things has slowly helped me see the cracks in its otherwise smooth, curved surface (ever noticed how everything in it is curved?)

I used to eat up its production design, pouring over my copy of The Art of Mass Effect in absolute awe. I still think it is an incredible artistic accomplishment, but now it no longer evokes that same sense of wonderment as it did. Similarly, where once I would think Eezo and the mass effect itself were brilliant pieces of practical world building, closer inspection reveals how utterly inconsistent it truly is — something which I'll almost certainly write a post about... some day.

But the thing I still love with the same intensity as I did nearly a decade ago, and also what causes me the most pain, is the Codex. Oh, the Codex! What a beautiful, wonderful piece of writing it is! It's a god damn shame the game's story writers seemingly don't agree, what with how they consistently ignore it in the actual story.

You see, when talking about Mass Effect as a setting, you actually need to specify which Mass Effect you're talking about: the one that's written down on the Codex, or the one that's shown in practice to the players as they make their way through the trilogy. Things which are outlined in the Codex are shamelessly ignored over the course of the games with shocking regularity. How many times have I landed on a planet in Mass Effect 2 where its blurb explicitly stated the air is toxic and it is devoid of life only to, on the ground, have Shepard stroll about without their helmet and stepping on grass-like plant life on the dirt paths. Or how every single time we see spaceships duke it out, it is markedly not in any way like the multi-paragraph long, in-depth dive on the dynamics of space combat outlined in the Codex.

What drives me mad is just how good this otherwise ignored material is! It's just such a waste, and I feel really bad for the person(s) responsible for writing all that. I see you and your work, and I love it! It is in part as a dedication to these individuals who have had their hard work trodden upon that I have made this series of posts.

Uncharted Worlds, Charted

If you actually care to look, you might be surprised at just how much detail you'll find scattered across Mass Effect's (star) maps. Each planet has its own little summary, with its particular characteristics, history and/or curiosities, in addition to the statistics provided for each world.

Considering Mass Effect The Firsteth™ alone had 41 individual star systems, each with an average of  ~4 worlds-ish, we have in the order of one-and-a-half hundred individual worlds, each with their own unique descriptions. Even if these descriptions are around a hundred words long, that still comes up to 16,400 words. That's an entire novelette's worth of bespoke information.

And it's not just any information either — it's plain to see that a lot of effort went into making these! The degree afforded to each world certainly varies, but someone laboriously sat down and seriously thought about these worlds, arguably just set dressing, with loving care, and it shows. It's a big part of what made me be so awestruck by Mass Effect and its world.

So once I got Mass Effect: Legendary Edition and started playing through the Trilogy, I decided to stop and note down all of the information on all of the worlds from all three games, and compile it all into one all-encompassing database with all of this information, as well as extra parameters calculated from the given ones, such as planetary and stellar masses, planetary densities and whatnot.

As of writing this, the document for Mass Effect The Original is fully compiled, and I just need to add in an Appendix to it before releasing, which I intend to do on Part I of this series.

The doc for Mass Effect 2 is almost nearly done as well, just missing a few worlds from one specific cluster, and a similar Appendix addendum which can just be copy-pasted from the first document. It'll be released in Part II of this series.

The doc for Mass Effect 3 however does not exist, as yet. I haven't finished ME2 and therefore not started 3, so yeah. God only knows when it'll be done — especially considering that it is both the longest of the three games and the one with the biggest map — but when it is done, it'll be Part III of this series.

Finally, once all three documents are out and about in this great wide world, I'll do a post-mortem/conclusions post where we can try to make sense of some of this data in Part IV of the series. In particular, I intend to try and locate the different clusters as to where they would be in the real Milky Way galaxy, or at the very least narrow down where they wouldn't be.

So put on Sam Hulick's Uncharted Worlds on a loop as we go on a deep dive into the Astrography of Mass Effect.

🎵 Doo Dee Doo, Doo-Dee Doo-Dee-Dee; Doo Dee Doo, Doo-Dee Doo-Dee-Dee...

 

Introductions Are In (Dis)order

I'm not quite sure how exactly you've found this place considering that, as of the time of writing, there's literally nothing that could have brought you here.

And if you're from some point in the future, looking back to the start of this blog seeking answers as to what exactly it is about — look, I have no idea either. 

Well, I have some idea.

Vague notions at best, really.

⬢ Who Are You?

I'm Gabriel Fonseca, but most anglophones I know just call me 'GAB'. I'm currently, as of writing this, an Astronomy undergrad student at UFRJ, the Federal University of Rio de Janeiro (do not ask for how long), where my area of study is planetary systems and orbital mechanics.

From 2018 to about 2022 I was a member of UFRJ's rocketry team, Minerva Rockets, and around the same time I also started working for The Sojourn Audio Drama, at first as a Science Advisor and subsequently, after a convoluted and somewhat nebulous sequence of events neither I nor my boss are entirely sure about, ended up as one of its Associate Producers as well.

In the time left over between all that, I do a bunch of random stuff — I write code, bumble around in Blender, catalogue and compile information about fictional worlds, think about completely useless and impractical things that amuse me nonetheless... and I even write something useful every now and again, imagine that!

⬢ So What's This Place, After All?

The point I'm trying to make is: I'm all over the place — and I fully expect this blog will be as well, in best ADHD fashion. Only time will tell what it'll be about, though like I said before, I have some vague notions.

I've always been a big sci-fi buff (if my career choices weren't a dead giveaway). I love fiction, I love worldbuilding, RPGs; all that classic jazz — so you can very much expect to find that kind of stuff here.

As examples of the sort of thing you'll eventually find in this blog (probably), here are some of the posts ideas I currently have in mind:

⬢ A thought piece on the practical challenges of Astrogation that most of science fiction so far has failed (or deliberately neglected) to address.

⬢ An essay on the architecture of Dwarven mountain keeps, and the challenges that would need to be circumvented were they to be built in real life.

⬢ A full survey of all star systems and planets in the Mass Effect game trilogy, in Google Doc form, with calculated parameters based on given information to find out stats not given by the games, such as stellar mass, planetary density, etc.

⬢ A post series wherein I flesh out the Regina (Spin 1910) system from the Official Traveller Universe (OTU) — I'm a huge fan of Traveller — based on extant canon information and modern exoplanetary science.

⬢ An article about the unassuming nightmare that is timekeeping, the miracle that is the modern Gregorian Calendar, and specifically timekeeping in the OTU.

And beyond that, I have a bunch of personal projects that I intend to publish someday, including a fantasy tabletop RPG setting and a story I'd like to one day turn into a graphic novel. Posts related to those are most likely to show up. Eventually.

Speaking of 'eventually', with what regularity will posts be appearing, you ask? Why, without any semblance of regularity whatsoever! Odds are posts will appear as my free time allows me to write them, or whenever I happen to hyperfixate on something instead of working on the myriad things I should be doing instead.

Either/Or, really.

⬢ So The TL;DR...?

In this blog, expect a lot of posts about general aspects of Science Fiction and Fantasy, real-world celestial mechanics, planetology, and astrocartography; meticulously compiled lists of things, ruminations on fiction, writing, game design, and tabletop role playing games — particularly Traveller — and other miscellanea that make me go 'Ooh, shiny!' and want to share it with the world.

Hopefully, it'll be as fun for you as it'll be for me.