Look, I get it. It's nice if she's 18. She can be shipped with anyone, it makes things simple, and the encyclopedia says that's how old she is, and that she was only petrified for 2 years.
Here's the thing: we have 3 winters in that time lapse montage before she revives. Not just in the anime, but the manga panels too. Those winters are of places in Japan, and the anime shows the passage of time by following her pets. It's extremely cute, a good counterpoint to how sad the situation is, and makes it clear 3 Northern Hemisphere winters have passed. This is important since March is the very beginning of spring in the northern hemisphere, but autumn in the southern one.
Both can't be true.
Let's talk about that, but first let me tell you about promotional material like that encyclopedia and how canon it is or isn't for a while:
A published fan book or encyclopedia is great for keeping a timeline and adding fun details to the characters, but humans are fallible and even the authors can get things wrong in a time crunch. Maybe their notes said one thing but they ended up saying something else in the actual book/show. The Dragonball Z fan books are famously incorrect and inconsistent. Merch fun facts and promotional images, even if the text copy on packaging/in the magazine/etc. is approved by the author, from a host of franchises is full of mistakes. It's a common problem. So what do we do?
Well, not this:
Let me introduce my dear mutuals to the idea of Alpha and Beta Canon. (No relation to A/B/O.) We Trekkies know this one from way back! The Apha Canon is the primary source: the actual media itself and nothing else. Even if it was written by Gene Roddenberry or said by Leonard Nimoy, anything that isn't the actual episodes of the Star Trek show is Beta canon. Think how some authors tried to sprinkle some LGBTQ into the cast of their books in the 2010's well after their publication. For the most part none of that contradicted anything, but none of it was even hinted at by any detail in the original media.
To say it another way: Death of the Author enthusiasts will ONLY ever consider Alpha Canon. To them, everything else is fanfic even if it came from the author.
The interviews and front matter fact sheets that say Gen Asagiri has poliosis and Sistus Inversus Totalus are beta canon - it is an idea that was meant to be plot relevant, but in the end that plot was changed and Gen's abnormal medical situation, which is hinted at in how certain scenes are drawn in both the anime and manga, never comes up explicitly. The poliosis is beta canon based on how he's drawn, the SI is arguably alpha canon because of the lie detector scene. It's a bit like how we have to keep track of what is a headcanon and not correct the show using a fan theory - even if there is, canonically, a big fat plot hole there. When two sources disagree, Alpha canon always wins when talking about what the media actually said.
For Dr. Stone, that means the manga and the anime. The encyclopedia and official website, no matter how helpful, are Beta canon. If the encyclopedia or promotional fact sheet contradict the manga or show content, the encyclopedia or fact sheet is the one with the error. It's supplemental material to the main series, merchandise not main content. If the wiki is based on the encyclopedia or an interview that contradicts the episodes, then the wiki is wrong to do that. The beta canon is only correct as long as it doesn't contradict the anime or manga. Everything in the encyclopedia is accurate and canon, unless it contradicts the show. We call those contradictory bits a retcon or a mistake.
So how old is Suika, ignoring the encyclopedia?
Well, we meet her at 9 in the spring. Her birthday is September 9th according to a fact page printed in a manga volume and she does state her age in the manga at one point. So she's 10 for the Grand Bout, 11 on the Treasure Island trip, and turns 12 on the ship while in the Pacific ocean well before Xeno is kidnapped at the beginning of December. The encyclopedia agrees on that chain of events, so she is 12 when Joel's petrification beam arrives 100 days after Xeno is captured.
100 days after that slightly vague date brings us to sometime in March. 3 winters in the northern hemisphere from March is going to be at least 3 years, maybe a few months more. Subtracting just 3 whole years from the time Senku counted during his second petrification is going to give us the oldest she can possibly be. She could canonically be a little younger if she gets revived later in the calendar year, and we have no indication of what month she wakes up in because it's the Amazon.
(Tiny rant: in a belligerent DM I was told by someone who was quite sure Suika had to be 'legal' with how she's drawn so sexy that the pyramid shaped place we saw in the time lapse and manga panels was not Roppongi Hills, the Kingdom of Might camp location, but the Medusa pyramid, so these were Southern Hemisphere winters. Allow me to point out that it never snows in the Amazon Rainforest. No, not even with climate change reversed. It's like 7°C for an hour on the coldest night of the year, and Senku didn't put a flag pole or radio station on the medusa pyramid. That's in Japan.)
Senku says he was petrified for 7 years in the anime, I haven't gotten there yet but I've been told in the manga he gives a more precise date of about seven and a half years. So that's 4 or 4.5 years Suika canonically lived alone at max for the anime and manga respectively (our poor baby girl!)
12+4=16, and half a year from March gets her to 17 tops. If she was petrified for a couple extra months that means she's certainly still 16 chronologically even if we pass her birthday before Xeno gets woken up. 16 is how old Senku was when he first met her. How poetic, how pure, it's so beautiful. Why are you trying to ruin that with gooning? (Ignoring the incredible psychological damage that much isolation would cause like OMG this manga ignores that whole thing, her social development should be so stunted.)
We're missing a year off the encyclopedia's assertion at best. Considering how long building a ship will take, the author could have easily confused the age she is when she revives Senku with her age when they leave South America. Inagaki is a human man with a job, perfect machine accuracy is not a requirement for him to be a fantastically creative author.
But some people will say she is 18 because that's the top Google result and what the AI says is the correct answer. Don't be that guy on reddit about it and badger someone for hours if they don't have the same head canon about it as you do.
This is not my typical art or meme post but a doubt surfaced in the Mcspirk Discord server about TarsusIV and if Kirk was on the list to die or to survive. So I made a kind of shallow dive in the net to see if I was able to find an answer, and I could say I did, but boy did I also find something I was absolutely NOT expecting.
For the record canon or alpha canon in Star Trek is what we see in the shows themselves.
(Some people may include here scriptwriters or directors publications/comments and interviews relating their work on the show and their intentions while making it, in general any of the key people that contributed to the canon we see in the shows. For others this is considered beta canon so it's a kind of grey area.)
Beta canon is all the rest under the Star Trek brand; novels, videogames, manuals, comics, etc.
Having established that more or less, here we go:
In alpha canon the answer to if Kirk was in the list to die or survive is; "it's tricky" xD
Memory Alpha in all accounts points to him being one of the other 4000 people that survived the mass execution, although it is not exactly specified that he was on any list to survive. There were previous scripts where Jim says he was, but it was scrapped among other things. Still, if Kodos executed the 4000 colonists all together in the antimatter chamber, and we haven't heard of any escapees or switches between people, I think it's safe to say he was on the list of survivors. However, I think it's important to note that we don't know if later Kodos just chilled, ordered more people killed or there were more deaths due to his ruling the more the situation became dire. And we also don't know how long he lasted in charge, since I couldn't find an exact time when help arrived either; it just states it arrived earlier than expected but too late to save the 4000 killed. So we can't be certain how much time elapsed from the mass execution till help finally got there.
Kirk is listed as a survivor of the TarsusIV Massacre, that encompasses all the struggle since what would be the uprise of Kodos and ordering those executions, till the unknown time later when help finally arrived. But we seem to be left to wonder if he could have been sought for later executions or persued in any way. In fact when we think back at what happened to his friend Tom Leighton, who was also a survivor and one of the nine witnesses, it is understood the damage to the side of his face either was caused by Kodos himself or took place during the massacre at least, maybe caused by Kodos enforcers.
Since we don't know exactly what happened and for how long after the mass execution, we can't be sure what or who was the cause. Like most of it, it's left to interpretation. But when you get into account that him, along with Jim and Kevin Riley, who were all rather young then, are from the few people who could identify Kodos because they saw his face, added to his wounds, makes you think that at least there was some big turmoil and, be it on purpose or not, these kids ended either in Kodos presence himself when most didn't even know his face, or could retrieve that photo we see in the TOS episode from Kodos' headquarters or some other important place that may store such data. As one ST Discovery novel (beta canon) suggests and also tells us more of what transpired after the execution.
So yes, alpha canon, or "the" canon left it ambiguous on purpose, since any intent to specify was scrapped before the TOS episode Conscience of the King was produced.
But here is where it gets juicy; beta canon (specifically Memory Beta) tells a very different story, one that made me have to read the paragraph twice and fact check because wtf xD
Two novels you'll see listed in the screenshot detail that Kirk was, in fact, on the list to die, but he escaped, saving Kevin Riley while he was at it. And not only that, but that Kirk was saved by SAREK who MELDED with him to erase the memory, because he also saved KODOS and gave him his new identity (wtf Sarek? You did that because you thought it was the logical thing to do or how come?? This could have tremendous implications...)
I don't know if any of you guys knew this but I sure didn't and the fic potential for this is unimaginable xD Maybe many of those that made Tarsus fics including Spock and/or Sarek there are based on this piece of beta canon but yeah, shocking.
I'm aware that Shatner touches on more about what happened in TarsusIV in some of the ST novels he wrote, like "Star Trek: Academy #1 Collision Course" and the "Autobiography of James T Kirk". For the latter I believe I read an excerpt some time ago that talked about riots and the situation getting really violent, but I couldn't find any information in this small search and I don't have the spoons to read the book right now, so take it with a grain of salt.
In the end it is all up for interpretation and you can go either way, but you sure get some interesting details in the various levels of canon xD
In the Star Trek universe there is a colossal library that takes up the bulk of a Dwarf Planet called Memory. So, when creating their fan wikis, the fans named it Memory Alpha. It was one of the first coherent fan wikis, ever.
This is where the term Alpha Canon comes from, and it refers to information seen in TOS, TNG, DS9, VOY, and ENT, along with their movies. But, there is also a large series of books and a giant stack of technical documents. The books don’t necessarily agree with each other, as most large canons do. Worse, the writers NEVER read the technical documents, meaning the technical documents don’t agree with the series. The fans then created a second wiki to include all of this new, non-Alpha canon data and called it Memory Beta.
Ergo,
Alpha Canon: Primary Series
Beta Canon: Primary Series + Auxiliary Series + Tech Docs
Note: The new movies happen in The Kelvin Timeline. Long story short, the USS Kelvin goes back in time and timey-whimey shenanigans change the timeline. Discovery is in the Kelvin Timeline, which is for the best, as they NEVER tried to make their series fit into the Star Trek canon.