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Vulcan years vs. Earth years

Spock was around thirty-five at the time (based upon his age being established as thirty-seven in "Yesteryear" and backtracking a couple of years), and they did age Jane Wyatt a bit, to make her seem more believable as Spock's mother, so figure Amanda was in her mid-twenties and just getting established in her teaching career when she met Sarek, putting her, most likely, in her early to mid sixties in "Journey To Babel".

They also aged up Mark Lenard. The big concern being that otherwise, he looked more like Spock's brother rather than his father.
 
Any questions or corrections?

Only a suggestion: in the 23rd century, humans would probably be older than they appear to the 20th/21st century eye. So there's plenty of leeway there for making Amanda a relatively mature mother.

Of course, Sarek might have logically decided that human women are at optimum child-bearing age between 13 and 17, which is more or less what nature originally intended. Or Spock might have emerged to this world without having to abuse the biological facilities of his mother, thereby eliminating her age as a factor.

OTOH, there's little reason to oppose the idea that Spock was born 35 years before "Journey to Babel", or 2231'ish by most probable TOS dating. It's just something that's not carved in stone, thanks to the vagaries of TAS dating and the subject matter of this thread.

Timo Saloniemi
 
On the previous page of this thread. :vulcan: :p

ENT did visually establish Andor as a moon of a ringed gas world, so the somewhat similar TMP view of Vulcan's sky might be considered sufficient proof, too.

I mean, the nearby planet there looks more rocky than gaseous, but OTOH it is so gigantic on the sky that a gas giant/moon setup might be more likely than a rock giant/moon one...

Since the huge companion world is absent from most of our views of Vulcan, though, I'd rather believe in the idea of an occasionally "visiting" companion world than of a world that Vulcan permanently orbits at close range. I mean, we have seen some fairly distant vistas of Vulcan in the movies and ENT, yet have failed to get this "motherworld" in the same picture with Vulcan even in these wide shots.

Timo Saloniemi
 
Hello TrekGuide.com,


That’s an interesting approach to this question. I managed to find a few clues when I was trying to get an answer too, but I can’t claim that this is exhaustive. Spock seems to have been covered in detail already, including the supposition that he’s 35 in “Amok Time” that I kidded myself I’d managed to work out all by myself, so:


T’Pol
Revealed very little, other than to say she’d be 66 at her next birthday in “Zero Hour”. Since that story was in February 2154, it implies that her last pon farr would have been in 2151, presumably before “Broken Bow” in April. The next would be in 2158, which again we wouldn’t see.


Tuvok
A minor nitpick here, since although he says he’s 29 at the time of STVI in “Flashback”, the stardate he quotes in “Unimatrix Zero, PartI” is 38774. Some interpretation’s obviously required there, so I’m not saying your suggestion’s wrong, but it is an interpretation.
“Ex Post Facto” and “Alice” establish that Tuvok experienced pon farr in 2304.
Although saying “Homestead” establishes anything with any certainty is dubious, it does suggest that the seventh series of Voyager is in 2377 and 2378. What is certain is that it’s Tuvok’s birthday in “Fury”, and Janeway says he’s not far off “the big three digits”. Later, in “Body & Soul” Tuvok experiences pon farr. Janeway helpfully points out that he had a similar bout of Tarkelian ’flu “exactly” seven years before.


My own feeling is that Vulcan and Earth years were used pretty much interchangeably in the scripts, giving the very clear impression that they’re a very similar length. Assuming that pon farr is linked to age as it seems to be for Spock, then it rather unhelpfully implies that Tuvok is going to be 98 in “Fury”, and that doesn’t fit with “Flashback”, since he’d be 119 (so still due a pon farr). Nor does a pon farr in 2304 fit with Vulcan and Earth years being about the same length.


I’ll repeat what I’ve said elsewhere, though: 40 Eridani is not written in stone as the Vulcan star system. In fact, the only direct evidence is the stated distance between Earth and Vulcan. This strongly suggests 40 Eridani, but a lot of distances have been clearly expressed in Star Trek, and they are very often wrong. Trelane is 900 light years away? What he’s seen of Earth is far less than 900 years ago, so something’s wrong somewhere. Is Kronos 1,000 light years from Earth? Probably not. That’s just my opinion and others will tell you different, I expect.

Timon (who eventually came up with something that sort of perhaps worked, but not well enough to start shouting about it in this thread)
 
In season 4 of ENT, is was stated that was 16 light years between Vulcan and Earth. If Vulcans are speaking Standard, I would expect to have them quote their ages in Earth years.
 
Although saying “Homestead” establishes anything with any certainty is dubious, it does suggest that the seventh series of Voyager is in 2377 and 2378. What is certain is that it’s Tuvok’s birthday in “Fury”, and Janeway says he’s not far off “the big three digits”. Later, in “Body & Soul” Tuvok experiences pon farr. Janeway helpfully points out that he had a similar bout of Tarkelian ’flu “exactly” seven years before.
Yes, perhaps it is futile to try to compile a specific date system based on canon references, when it is clear that the writers on one single series (let alone four series and 11 movies) seemed to be making it up as they went along (and disregarding what they had already made up).

It would make sense, if I were a TV producer, to have the characters' ages written down somewhere, or generally know in what decade they were born. In "Flashback," Tuvok was clearly well over 100 years old, as stated in the episode. But in the later episode "Fury," Janeway says Tuvok will soon reach "the big three digits." Clearly the writer of the latter episode did not see the previous episode, and there was no "writers' bible" or technical consultant on the show to give guidance about such things. ...

And who knows where they got the Stardate for Tuvok's birthdate in "UNIMATRIX ZERO" PART II. Someone probably just made up a random five-digit number and nobody stopped to check when Stardate 38774 might have been. (It's probably just a coincidence that adding a decimal places it during The Original Series.)

You'd think that, by the last seasons of "Voyager," the producers would realize how many of us nitpicky fans are watching, and they would pay attention to these details, knowing that they would be endlessly debated decades later.
 
You'd think that, by the last seasons of "Voyager," the producers would realize how many of us nitpicky fans are watching, and they would pay attention to these details, knowing that they would be endlessly debated decades later.
They have simply no idea how much Trekkies obsess over trivia...they still think we're normal people.
:lol:
 
...the stardate he quotes in “Unimatrix Zero, PartI” is 38774. Some interpretation’s obviously required there, so I’m not saying your suggestion’s wrong, but it is an interpretation.
Makes sense; 38774 could be the same thing as 8774. After all, if stardates increase by a thousand units every year (like they appear to do in TOS and TNG both), then a four-digit stardate is going to "roll over" every decade. And a five-digit one will reset every century, so there probably is a sixth digit to the TNG era dates, one that our heroes drop for brevity. Our TOS heroes would drop the decade digit, too, during a five-year mission where everybody is aware of the decade anyway.

Trelane is 900 light years away? What he’s seen of Earth is far less than 900 years ago, so something’s wrong somewhere.
...Such as the fact that Trelane lives on a warp-mobile planet?

Is Kronos 1,000 light years from Earth? Probably not.
To be sure, ST6:TUC doesn't exactly claim this. It only claims that Gorkon's ship meets Kirk's a thousand lightyears (probably Kirk's terminology for what Spock would insist is 672.12 ly) from Earth. Perhaps Gorkon wasn't coming from Kronos?

"the big three digits."
You mean 123?

Timo Saloniemi
 
...the stardate he quotes in “Unimatrix Zero, PartI” is 38774. Some interpretation’s obviously required there, so I’m not saying your suggestion’s wrong, but it is an interpretation.
Makes sense; 38774 could be the same thing as 8774. After all, if stardates increase by a thousand units every year (like they appear to do in TOS and TNG both), then a four-digit stardate is going to "roll over" every decade. And a five-digit one will reset every century, so there probably is a sixth digit to the TNG era dates, one that our heroes drop for brevity. Our TOS heroes would drop the decade digit, too, during a five-year mission where everybody is aware of the decade anyway.
But 8774 is not a Stardate within the timeframe of TOS, such that if Tuvok were born on that Stardate, he would be 29 (Earth or Vulcan) years old during "Star Trek VI."

I think it is more likely that Tuvok was born on Stardate 3877.4 (during the second season of TOS), and that the decimal place was just left out in "UNIMATRIX ZERO" PART II. This would fit better with him being 29 during "Star Trek VI."


http://TrekGuide.com/Stardates.htm#Tuvok
 
But 8774 is not a Stardate within the timeframe of TOS, such that if Tuvok were born on that Stardate, he would be 29 (Earth or Vulcan) years old during "Star Trek VI."

Within the rules of the "missing digit theory", it is.

That is, there'd be a stardate 8774 some 1.5 years before the first televised segment of Kirk's five-year mission, which in stardate order would be "Mudd's Women" (SD 1329). Possibly in 2264-65, then, as we canonically know his five-year mission spanned 2266-2270. And there'd be a stardate 8774 again a decade later, two decades later, and three decades later. TUC appears to take place in 2293, which would nicely fit the 2264+29 requirement.

OTOH, TUC has the opening stardate 9521, so by that theory Tuvok would have been born on a stardate that's no more than 1000 units higher (and three "missing digit units" lower, of course) if he's 29 Earth years at that time. That'd mean stardates (X)9525 through (X+1)0525, then. If those are Vulcan years, then they are slightly longer than Earth ones to yield SD (X)8774.

Granted that the TOS movies are the ones at greatest odds wrt the missing digit theory. TOS works just fine - indeed, it works much better if we assume TNG style but missing-digit progression than if we assume that one TOS season lasted for one Earth year! TAS has its quirks. TMP would fit in nicely, as would the movies 2 through 5, although not quite the way the Okudaic system assumes. The TUC/GEN pair is the unfortunate outlier here...

I think it is more likely that Tuvok was born on Stardate 3877.4 (during the second season of TOS), and that the decimal place was just left out in "UNIMATRIX ZERO" PART II. This would fit better with him being 29 during "Star Trek VI."

That theory is a perfect fit, yes. It's not as if our other heroes wouldn't have fumbled the decimal a few times...

Other funny stuff: in TNG "Dark Page", SD 30620 is indicated to be eight years before the birth of Deanna Troi. If SD 41150 from the TNG pilot is 2364 (or perhaps 2363, assuming a stardate year spans a Hollywood season and rolls over after the summer, as indicated in many places), then a birthdate of SD 38XXX would have Troi be just three years old at Farpoint... Do we have to figure out "Betazoid years" now? In this case, we can't plead decimal marker misplacement, nor missing first digit. The first digit must be in error in terms of the TNG system - but in the missing-digit TOS system, the first digit out of five is not canonically defined. So perhaps we could plead a discontinuity in systems, with the first digit out of five getting redefined some time after the Troi wedding...

Timo Saloniemi
 
Hello Timo (we seem to be getting confused with each other already) and everyone else,


With anything like this, it’s all in the interpretation!

I’ve tried several times to get a system of stardates that would simply cycle through from TOS to TNG. You can get close, but not close enough for it to be worth trying to put up with the problems. I’m a sucker for stardate systems of any description though, so I crunched a few numbers assuming that there was only one major recalibration (or resetting of the zero date), for the start of TNG stardates. Using 1000 stardates = 368 days gives some interesting results, and using 1000 stardates = 1469 days dispensed with the need for hidden prefix numbers, but gave some very, very odd numbers indeed.


I’ve looked in detail at the internal timelines of individual stories (thanks to the availability of transcripts and screencaps for just about everything), and I found they only work if stardates progress at a rate of one every 24 hours or so. That means that the whole system has to be a lot more complicated than it first appears, as if that’s not complicated enough. It’s a pity that Star Trek publishing won’t allow the sort of books that Doctor Who’s does:
http://madnorwegian.com/137/books/a...story-of-the-doctor-who-universe-2nd-edition/
http://74.54.78.50/~telosco/culttv/timelink/cover.php
If nothing else, it would mean some more permanent reference works on this topic than websites can provide, or forum threads.


Whilst a regular cycle of stardates appeals very strongly to my sense of order and neatness, in practice I’ve never managed to come up with one that doesn’t require too many compromises. I also can’t help thinking that if there are hidden extra numbers in stardates, why aren’t they used? Log entries are one thing, but personnel records, for example, would surely use them (assuming stardates are real, of course). Tuvok might be using one for his date of birth, but what about all the other times they aren’t? Like Joran Belar’s birth and death dates, or the revocation of Harry Mudd’s licence?


I can’t help thinking that Lwaxana Troi’s diary is something of a red herring, since you can wave your hands and suggest that all the original dates were in the Betazed calendar, and automatically translated into equivalent stardates. The computer used the most recent occurrence of all the dates, as a default. That would mean there’s a 23 earth-year cycle to dates on Betazed, with the same dates (perhaps a “year of the monkey”-type thing) coming up in 2328, 2351 and not again until 2374. (Your years may vary, since these are my own calculations. The basic idea doesn’t require a particular stardating system.)


All of this has slithered somewhat off-topic, so getting back to the Vulcan calendar: Making Vulcan the moon of a huge gas-giant (or even quite a little one) does have a problem, in that anything that big in the sky is certain to have tidally-locked the rotation of Vulcan, according to what we currently understand. That means that one day on Vulcan is going to last more than five earth days, if Vulcan’s the junior partner. Even taking something more like the arrangement in the “Star Trek Star Charts” only gets it down to two and a half days. I decided to try and live with that, because a double planet’s an interesting idea, and the other alternative is that the sister planet is very much smaller than Vulcan, is capable of no other description than a moon, and Mr Spock’s pants are very definitely on fire. Rejecting “Yesteryear” altogether and insisting on the Director’s Cut of TMP is another option, but it isn’t the one I’ve wanted to go with.


I’m afraid the sheer size of the object in Vulcan’s sky makes me very dubious about the whole planets in separate but grazing orbits theory. A setup like that just isn’t stable enough to last for millions of years. I can’t claim to have done all the maths, but the beauty of Newton’s model is that gravitational attraction depends on how big something is and how far away it is. That means that when you have something in the sky that’s hugely bigger than the sun, the gravitational interaction is going to be large. Very large. Like being dragged out of orbit and falling into the sun large, or breaking up into an asteroid belt large, or flying out of the star system altogether large.


The relationship between distance from a star and planet surface temperature isn’t something we understand in detail yet. Vulcan is supposed to have a thin atmosphere, so I’m not convinced that there can be a huge greenhouse effect, although a lot of dust suspended in the atmosphere might serve to trap heat. From what I can see, expert opinion is that it would actually cool the surface, given those dire predictions of nuclear winters. On balance, and not as an expert, I think Vulcan is likely to get more light from its sun than earth does. How that translates into a Vulcan year depends on how bright a star it orbits.


Of course, physical laws as we understand them often take something of a holiday during the course of many Star Trek stories, but it kind of kills all the fun in this sort of debate if you decide not to bother with any of that.


My own attempt to balance the available evidence only really went anywhere when I decided that Vulcans don’t count using years, in the sense of one orbit around their star. The ancient Greeks used the Olympiad as a calendar, counting in four-year units. If the Vulcans count years in pairs for calculating ages and in their calendar you end up with something more plausible, even in relation to 40 Eridani, since the unit then becomes a little longer than an earth year, instead of massively shorter.


Numbers are very flexible, and can be shoved around to satisfy all kinds of unreasonable assumptions. If the Vulcans were to use a base-12 counting system, then Tuvok won’t be 100 in Vulcan birthdays until he’s 144 by our count. Naturally, arguing this would open a huge can of worms, since what base is any number relating to Vulcans in? And wouldn’t it be too coincidental that the single digits “ten” and “eleven” never seem to crop up? Maybe you don’t hit the big three digits on Vulcan until you’re a hundred and eleventy-ten years old.:)


Well, once again I think I’ve rambled on quite enough, and hopefully not too much for everyone’s patience. I hope TrekGuide.com finds something that works for him, but definite, convincing and absolute answers are very elusive, in my experience.


Timon (not Timo, but it is my real name, not just a deliberately confusing pseudonym)
 
Just to throw a little fat on the fire, here, the orbit of a moon or junior planet around a larger planet is not determined by their physical sizes, but by their masses. Given a planet's mass, it's size is then related to its density.

To help resolve weird problems with Vulcan being the junior planet in a pair with a large gas giant, may I suggest that Vulcan is as dense as or denser than the Earth (5.51 g/cc), and that its large companion is as dense as or perhaps even less dense than Saturn (0.69 g/cc -- less than water!). Saturn doesn't have the tremendous gravitational or magnetic fields that Jupiter does. But everyone seems to be comparing T'Khut with Jupiter (density 1.33 g/cc - twice that of Saturn) instead of Saturn, making things difficult.

A very large planet that is not very dense will have a lower gravity, and therefore a moon or junior planet can orbit closer to the surface without having an unnecessarily fast orbital speed or other problems associated with a close orbit around a high-gravity planet, such as tidal locking. If T'Khut is a low-density gas giant like Saturn (perhaps even less dense), then Vulcan can act like a normal planet comparable to Earth, and yet still have this hulking behemoth of an object filling the sky.

Does this help?
 
Dear Timo,

This is just a very quick note to say that after writing a knee-jerk "Oh no, it isn't!" reply to your interpretation of Tuvok's birth-stardate, further reflection has made me think that my arguments were pretty much nonsense, and you are right. Thanks for a very helpful suggestion.

Aahz, I've not tried pushing the densities of the two planets to extremes. That's partly because Geoffrey Mandel's Star Maps-Star Charts-Officer's Manual interpretation of Vulcan sees it as a large-diameter, low(ish)-density world. I'll have to play around with the data and see what comes out.

As a last aside, I'm not any sort of planetary scientist. My modelling of alien worlds is done very simply on spreadheets, using the nice, simple (but surprisingly accurate) information in GURPS Space (alas, it's a proper book, and costs money, so I can't provide an easy link).

Timon
 
What do we have to canonical quantifable data besdie lower atmospheric pressure and hotter that a Standard atmosphere? I could make some models if there was anything concrete to go on.
 
...

the nice, simple (but surprisingly accurate) information in GURPS Space

...

GURPS Space is fan-freakin'-tastic. I highly recommend it to anyone interested in sci-fi science. It draws from lots of sources, both real and fictional.

--Alex
 
Hello everyone,

Since I insisted on bringing it up, I've worked through a number of examples for planets in close orbits.

Luckily for me, Stephen H. Dole of the RAND Corporation wrote a book called “Habitable Planets for Man” in 1964 that covers a lot of this ground. Although things have undoubtedly moved on since then, a lot of his conclusions still hold.

A helpful diagram on page 75 of the book establishes what is and isn't possible. The options for two planets close together are quite constrained. If the habitable planet rotates without significant tidal braking, then the companion world has to be smaller. My best guess from the diagram is that the biggest a moon can get without tidally-locking the Earth is around ten times the size of our Moon. The bad news is that the distance it orbits has to increase too. Again, my interpretation of the diagram puts the distance permitted at about twice the distance of our Moon. The resulting tidal force is quite low enough to avoid tidal locking, but the size of the moon in the sky is unlikely to be terribly impressive. Naturally, the size depends on the radius, and the radius depends on the density of the planet. Again, we're into guesswork here, but Mr. Dole's best guess is that the diameter will be around half that of the Earth. And the size in the sky? Only around the same size as the Moon. Slightly smaller, in fact.

Coming at it from a different direction, I decided that it might help to get some ballpark figures by calculating what different bodies in the solar system would be like if Earth had the same relationship to them that Vulcan's supposed to have to its companion.

First, I calculated what Saturn would look like if Earth orbited it in 24 hours, so that the length of an Earth day stays the same. That orbit would be at a distance of 193,587 km, or 3.332 Saturn radii, well outside the Roche Limit. But Saturn would be big. From Earth, it would cover 34.5 degrees in the sky, or 65 times bigger than the Moon as viewed from Earth. It's hard to see how you'd ever miss that in the sky, especially from orbit. This is the diameter I'm talking about, not the visible area. If you had a picture of the night sky with the full Moon on it measuring about half an inch across, Saturn at that scale would be over thirty inches across. I doubt anything of the sky would be visible in the picture, just bands of cloud. It's far too big to be anything like what I'm trying to match in Vulcan's sky. As a comparison, Saturn's moon Titan orbits much further out. One if its days is 15.95 Earth days long.

I then tried again, with Neptune, the densest of the gas giants. The Earth would need to orbit at 110,963 km, or 4.53 Neptune radii. Neptune would still cover 26 degrees in the sky, and be 50 times the size the Moon looks.

You may be thinking that the planet might orbit far enough out not to be tidally locked, and the gas giant would look smaller then, too. Not according to “Habitable Planets for Man”. Once you start getting too far out, then the orbit becomes unstable, and the planet is liable to go off on its own, and that's unlikely to be into a stable orbit. As I observed in a previous post, since the range of densities for “normal” matter is quite limited, once something appears in a planet's sky that's bigger than the sun, then there are only so many options that result in a habitable planet in a stable orbit.

Next, I tried Mars. It's smaller, still big enough to qualify as a sister world, and has a cratered surface. It would orbit the Earth at 43,704 km for a 24 hour Earth day (Mars would have a 24 hour day too in this arrangement), or 6.86 Earth radii. But, Mars would still cover around 10 degrees and be very nearly 20 times bigger in the sky than the Moon is.

Last, I tried moving the Moon closer in to Earth. For a 24 hour day when the Earth's tidally locked (as it would be at such a close distance), the two would be 42,409 km apart (the real distance is 384,400 km, so the Moon needs to move very close, by comparison). It would cover 5.5 degrees in the sky, and look 10.5 times bigger, which seems to be about right for the things in Vulcan's sky in “Yesteryear” and TMP.

So, there you have it. If the Earth keeps a normal length day, the thing in the sky either has to look enormous and fill practically all of the sky, or quite unequivocally be a moon. I tried to balance things in my own calculations by assuming a much longer than normal day for Vulcan, but I'm having second thoughts. The little evidence there is says that Vulcan days can't be that much longer than Earth ones, as far as I can see.

Last (and probably least), the “moonlet” that appears in TMP. If the companion planet's a gas giant (and it's nowhere near big enough in the sky, by my calculations) then it can simply orbit closer in. If Vulcan's the biggest planet of the pair, there's a problem. Put simply, moons don't have moons. The tidal forces make the arrangement unstable. You may recall that all those Moon orbiters eventually made “controlled impacts” with the Lunar surface. It wasn't just for scientific research, or because India wanted to claim their flag had been landed on the Moon. In the end, the probes would have fallen down whatever they did. My own theory is that if Vulcan is the larger planet, the “moonlet” is likely to be in orbit around neither of the bigger worlds, but practically stationary in relation to both of them, at one of the Lagrange Points. What's seen racing across the companion world is its shadow, not the “moonlet” itself. Perhaps not a very convincing theory, but it's the best I can manage. EDIT: And it's nonsense. I've looked at a screencap. That's definitely a solid object, not a shadow.

All the same, it seemed a bit pointless to go through all this and not reach a conclusion: Given the size in the sky, and the fact that it's never been visible from orbit, I can't help thinking that the object in Vulcan's sky is almost exactly the same size as our own Moon. Maybe the future will have a much more stringent definition of “moon” that disqualifies the moon-sized thing sharing an orbit with Vulcan. Perhaps Mr Spock can be a real stinker when he's in the mood.

I can't help wishing that the options had been a little less restrictive, but there you are. Or not, if you think this is all just too much for an unimportant background detail in a science-fiction story. Sorry for yet another long post, but this isn't something that lent itself to brief explanation.

EDIT: I've been looking at screencaps. The size of the objects depends pretty much on how big you think the full Moon would appear in each one. I'm not sure that the "Yesteryear" and TMP images can be reconciled with each other, or that the sort of conclusion I reach above is really possible. All this has very little to do with the theme of the thread. Sorry, TrekGuide.com. If I make any further progress with any of this, I'll start a new thread.

Timon, who hopes this is helpful rather than just confusing
 
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Habitable Planets for Man is based on outmoded physics.
Why are many hung up with Earth-Moon analogues. T'Khut, IMO, is an independent planet who orbit brings it periodically close to Vulcan.
 
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