Superman Through the Ages! Forum

One of the more interesting and so-very fifties science fiction ideas that was introduced during the Weisenger years was the idea that the reason Krypton exploded was that Krypton's core was made of uranium - and as a result of a chain reaction, the core exploded, turning Krypton into a gigantic atomic bomb.

Most later sources were vague about the hows of Krypton's destruction under Schwartz's tenure (and let's not even mention the clueless Black Zero story Carlin and his bootlickers inflicted on us).

But this fact might be interesting to use to speculate on what sort of planet Krypton was like.

DISCLAIMER: I'm not a scientist by trade, just an amateur making guesses.

For one thing, it means that it's possible Krypton might not be as large as we believe; uranium is a very dense metal. It's density is about 19.1 g/cm3.  Water, in comparison, is 1.0 g/cm3.

The average density of the earth is 5.5 g/cm3, making it the densest planet in the solar system. It's interesting to note that the density of most metals found in a planet is on average, about more or less 8.0 g/cm3 and the density of rock is (more or less) 3.0 g/cm3. Taking that the earth is part rock and part iron, the average of the rock and metal divided together is 5.5, the density of the earth.

(The average density of Saturn is .7 g/cm3, less than 1.0 g/cm3 of water - meaning Saturn could float in water - if you had a big enough bathtub.)

Using that same way of figuring out planetary density, we get a Krypton, part uranium, part rock, that is 11.05 g/cm3 - nearly twice the density of earth. Using this - and Captain Kal's 35 G figure, what would the volume, diameter, and circumference of Krypton have to be?

What would be some of the problems of a planet with a uranium core? Well, obviously the radiation; it might be interesting to account for why life on Krypton was allowed to exist and evolve at all.

The second is the fact that without a magnetic element (like iron or nickel) to form the liquid core, the planet has no magnetic field to protect it from cosmic radiation. This does not necessarily mean that the planet has no magnetic field; some gas giants in our solar system have magnetic fields, but have no core as a result of the unusual properties of some gases. This may account for Superman's phrase in many Kandor stories that "encounter with Krypton's atmosphere reduces my powers."

(Incidentally, I only recently found out that uranium was actually pale and silvery. Interesting - in comics and movies and so on, Uranium is usually drawn as yellowish or copper-colored.)

Actually Earth might be one of those planets as it turns out:

http://www.newscientist.com/article.ns?id=mg18725103.700

Refined uranium is a pale silvery metal, but in its natural form when mined uranium oxide is yellow.  During the refining process, uranium concentrate is called "yellowcake" due to its color (70-90% uranium oxide).

The idea of a core composed of Uranium is a little far fetched even if it is fun...probably present in small amounts throughout the universe's matter, it is simply uncommon...hugely dense, massive nucleus, and because of that mass why it can generate such energy (as Einstein suggested), a core of Uranium seems outside the realm of any normal planet's development...and its stability over any period of time...

Any normal planet.  Krypton was not a normal planet.

Its origin is here on the site.  It was created by a group of beings that live inside Rao(The Kryptonian sun) to stablize the sun's energy.  Throw out any idea of natural planetary devlopment.  Krypton is not going to follow the rules of other planets

Krypton is a more fun planet without convoluted and tortured attempts to make it scientific...and any attempts make it even more ludicrous...

They are comics after all...

Hi,

Remember Superman the movie?  Krypton's gravity was shifting (from memory)...  If we looked through a few comics that have Superman's origin repeated, we'll find a few other reasons why Krypton has exploded.  Once we find out (for example) that a planet cannot explode no matter what sort of core, then Superman will have another origin.  The main thing is that "Krypton exploded" - am I bad or am I bad?

Excellent thread topic per usual, Julian.

Quick comments since I don't have time for an indepth analysis at work right now ...

More massive planets are more likely to retain higher proportions of heavy elements.  Uranium certainly qualifies.

Natural uranium is mostly the U-238 isotope which is not fissionable so it's unlikely to be an instant nuclear bomb.  However, the small proportion of fissile U-235 in a planetary core made of the stuff plus the fact that the core is probably not pure uranium but a mixture of elements like our own might give us the equivalent of a planetary nuclear reactor that later ran out of control.  Perhaps the proportion of U-238 gradually transmuted to plutonium like in a breeder reactor and the mass became critical in Jor-El's time.

FYI, our own planetary core is rendered molten hot partly due to trapped heat from planetary formation billions of years ago but mostly due to heat of radioactive decay.

Our magnetic field is due to electric currents in the planetary molten core which would still be generated in a molten core largely made of uranium.  It is not mandatory for iron or nickel to be present to generate Earth's magnetic field just moving core currents.  For comparison, the sun is largely hydrogen and helium yet it has a magnetic field that dwarfs Earth's.  The sun certainly has those vast moving currents needed for a magnetic field.

The Earth has 10.75 g/cm^3 core density compared with the average density of 5.52 g/cm^3 for the overall Earth.

Iron has a density of 7.87 g/cm^3 compared with Uranium's 19.1 g/cm^3.

While that would tend to give us a Krypton core density 2.43 times the density of our own planetary core, the proportion of lighter elements in the outer planetary layers may compensate for that.  Natural giant planets tend to have higher gas content in the outer layers, like Jupiter and Saturn do, so the compensating density layers isn't a stretch.  It's also possible the other elements in the core may compensate for density making it somewhat less dense.  No planetary layer is a pure element of any kind or even close to it, though some elements tend to dominate.

While it may be possible to make a 35 G planet with a smaller mass, I don't think it can be much less massive than a brown dwarf mass (0.8 solar masses) or else Gresh's & Weinberg's objection about impossible densities rears its ugly head again.

It must be noted that not only does the Sun-Thrivers origin of Krypton -- reaffirmed for Post Crisis per Wolfman's History of the DC Universe books -- give an atypical planetary formation, but the details of Krypton's composition and structure suggest, if not a unique planet, certainly an exceedingly rare one. Perhaps only Daxam came close.

FYI, I just figured out that for a proportionate Krypton core largely made of uranium, only less than 1/480th of the uranium needs to fission to blow-up Krypton.  Of course, that would have to happen all at once instead of being spread out over years else the energy would harmlessly dissipate instead of exploding.

According to Maggin's "The Greatest Green Lantern of All!", Krypton had an erratic magnetic field.  Said field was capable of disrupting other stars
systems to the point of dooming them.

http://superman.nu/tales2/greatestGL/?page=3

That erratic field is consistent with an unstable planetary core.  The sheer power of a field that could do that to other stars in a space sector suggests it's powered by more than just ordinary radioactivity.  Instead, perhaps that erratic magnetic field was an early indicator of Krypton's coming nuclear explosion.  Certainly, the Guardians were aware of this.

The question I originally asked was, if planetary density is greater as a result of heavier elements in the uranium core, how would that affect calculations about Krypton's size and circumference, if we need to have it be brown dwarf mass to produce a superbeing? In other words, how BIG was Krypton?

Here's one interesting point about how Krypton may have been liveable despite a Uranium core - wasn't gold the most common element on Krypton, found extensively in the planet's crust and mantle? Gold has a property of absorbing radiation, like lead - in fact, use of gold sheets around uranium was how the current atomic model was formed and the nucleus was discovered. It may have been the case that the gold absorbed much of the radiation and made life on the surface possible for hardy beings.

Many life forms have different tolerance to radiation; bacteria can absorb nearly a thousand times as much as mammals can, and reptiles have shown resistance as well. It's not inconceiveable Kryptonian life, with a shield of gold, has such an immunity.

There are many, MANY problems with Maggin's "A Name is Born" story.

For instance, how could a whole race spring from just two people?

If Kryptonians sprang from space explorers, why did they spend so much of their history in a primitive state?

If all Kryptonians sprang from two space explorers, why is there so much variation in Kryptonian appearance if they didn't evolve on the planet? For instance, the blackskinned inhabitants of Varaho.

Here's the big objection: if Kryptonians came from elsewhere, and are not a product of evolution on Krypton...why would ANY of them exhibit unusual powers and abilities of the kind Superman does as a result of the red sun, just like Kryptonian animal and plant life has been shown to do so? Why would any of them be vulnerable to Kryptonite?

It also conflicts with the fact that except for a few comments told well, well after the story, there's no sign of Kryptonians even BEING from space, nothing to show this in their civilization or culture or tradition. It conflicts with established stories, unusual for Maggin, who usually understands previous rules.

Quick and dirty answer: I stick by the 0.26 Sun radius size I've posted elsewhere.  Krypton cannot be much smaller or less massive or else we couldn't build it with normal matter or have a 35 G gravity.  We can compensate for the uranium in the core several ways which I've posted earlier.

I'll post on your other comments later.

Great theory on how gold, and possibly other heavy elements, helped shield life from the radiation brewing in the core.  I like it.  Remind me to quote you on it in the future, Julian.

Re: a whole race springing from two people: That could be the result of genetic engineering  from their parent world for just such a possibility.  It may more logically be the result of the outworlder colonists' initial lack of adaptation to the relatively higher radiation and other mutagenic factors in the environment that caused a higher mutation rate in the early generations.  That would allow for the genetic diversity needed here.  While the heavy elements would shield life from the nuclear reactor in the core, the overall radiation levels would tend to be higher on a high-G world from the higher proportion of radioactives on the surface itself.  Conceivably, a space-faring race would have engineered their astronauts to have higher radiation tolerance though the mutation rate would still be higher for their offspring.  The inhabitants of Vathlo island may be an extreme case of genetic variance due to the higher background radiation.

Of course, it's entirely possible that others were marooned on Krypton so they weren't the only two, though that's not documented.

Despite our 'high' tech compared with our ancestors, one good nuke war and we'd be back to the Stone Age.  IIRC, someone once said WW 3 would be fought with nukes and WW 4 would be fought with sticks.  The same could apply to the colonists.  They didn't have the infrastructure to create nor maintain what they had.  They had no way to rebuild sophisticated microciruits when they inevitably failed.  They had no means of reproducing high-grade alloys.  The list goes on.  Without the infrastructure of their homeworld's eventually everything they brought with them would fall into disrepair.  Only after civilization had been regenerated to the point of their homeworld's could this occur.

Kryptonian humanoid powers are mostly based on gravitational adaptation according to LSOK, with the sun amplifying those base abilities to an incredible degree.  LSOK also does mention Krypton being colonized from outside twice: Once on the opening page of the story, and twice when Jor-El tells Einstein about the legends surrounding Krypton's origin.

Kryptonite happens to be the antidote to the Daxamite lead vulnerability.  Daxam is the parent world of Krypton according to TOLSH #325. It may be the generations of undirected Kryptonian evolutionary descendants both acquired the normal reaction to lead and an unexpected counter vulnerability to the once beneficial kryptonite.  Hey, we can't breathe water anymore like our fishy ancestors.  Also, Daxam has always been a pioneer in bioengineering.  The powers from gravity and sun differences may have been engineered so though they might not have anticipated the drastic effects of a yellow sun environment.  Others have suggested that it seems quite artificial for a potentially powerful race like the Daxamites to both be vulnerable to common lead yet be on a world curiously lacking in that very element.  The same goes for the powers of Kryptonians.  They suggest an Oan offshoot like the Guardians were behind both races, much like the Oans once created the Psion race.  We do know 10,000 odd offshoots of Oans departed Maltus and we only know the fates of about half a dozen of them (Guardians, Controllers, Zamarons, Leprechauns, Krona, mortal Maltusians).

Of course krypton was not made of ordinary matter.  Everything from krypton becomes super when under a yellow sun.  That includes totally inanimate objects.

Absolutely true, Ilozymandias.

But under red solar influence, it does behave like our matter.

It only acquires super characteristics outside Rao's influence.

Where in the comics have any kryptonians called their sun RAO?  According to E Nelson Bridwell Rao was originally the name of a sun-god.  In ancient times a moses-like figure made Rao krypton's name for GOD.  When Superman says Great Rao, that is basically the same thing as us saying good God or good lord.  


   Why super-matter (for want of a better name) would have such different properties under different stars?  No idea, but it should be treated as one of the biggest mysteries in the DC Multiverse.

Mysterious...impossible is more like it...matter having "stronger" properties under a yellow sun and a bunch of the planet tying together mythos of the 70s and beyond stretched real science to a dumb point, and it killed the cool fantasy as well...oh, and is Superman's costume strong on Neptune, or proportionately weaker?  Dumb and dumber...

As far as the founding of Krypton, it seems better thought of as a Romulus and Remis myth, I hope so, anyways... :D

I like the fact that all that old comic book science doesn't make any sense, it makes the stories even more fun for me, it makes me laugh, and laughing is a good thing.

I like how it makes no sense meself...trying to make sense of it makes it impossibly stupid...LOL... 8)

Anyone want to take a crack at the science behind the first sacking of Troy? :lol:

I think it was Einstein who said it.

Trying to make sense of it makes it impossibly stupid? Does that make those of us who try to anyway for the sake of fun, impossibly stupid? :P

no, just bored  :wink:

This is just me, no, not impossibly stupid, but trying to find continuity or real science is going to be an impossible chase...why not enjoy the fantasy and the fun?

For me, I have no problem with the interaction of Supes and the Green Lantern Corps, I have no real problem with the crisis (except what happened after), but overwrought explanations of the origins of the universe coupled with exact hominid duplicates all over the place in unlikely places and elements that are universal but somehow "stronger" in certain solar systems are NOT worth trying to explain. It doesn't make the fantasy any better, and the world of science laughs...

More accurately, you laugh (and others of the same mindset), MatterEaterLad.  Real scientists have held courses on comicbook science and written books on the matter and even discussed it on the internet and journalism articles.  Given your abhorrence of this matter, I think I can safely say you are not amongst the scientific community.  Do please refrain from speaking for it, then.

Yes, let's forget all the brilliant stories from the S.F. greats like Fox and Hamilton that did indeed examine the scientific implications of comics super-heroes.  Let's toss out Flash's aura, vibrating through walls, super-speed time travel, vibrating to invisibility, and Superman's heat vision 'cause they 'just don't make sense'.  Those are examples of brilliant scientific extrapolations from what the powers are about and could possibly do.

I agree with JulianPerez that scientific extrapolation in comics for its own sake is somewhat sterile and useless.  It must be coupled with adding value to the stories (which the above examples abundantly do).

But to disregard scientific extrapolation altogether is sliding much too far into the other extreme.  As abundantly proven by these examples -- which I've posted ad nauseaum -- the great Silver Age writers and the legendary editor, Julius Schwartz, all subscribed to this kind of thinking.  This is, afterall, a site devoted to celebrating the Silver Age.  To denigrate this aspect of it is not in keeping with that spirit.

Look, I'm not trying to start a fight.  I like you MELad and a lot of what you have to say.  But can you and the others please get over this?  Julian posted a legitimate question.  If you don't like it, then just stay out of the thread.  No one forced you to get involved in a topic that you don't subscribe to.

:D

Hmm, maybe I'm coming off as more adversarial than I mean, but that can happen with writing posts on the internet...

I intended to disagree with trying to find real science behind a lot of the comic's plot devices (many of which I have always liked), but I wasn't trying to muzzle what others like or get personal...my apologies if this is how it came across to anyone...

We've had this discussion before, Ilozymandias, or at least someone else has had it with me here re: Rao = Krypton's sun.

To rehash it a second time ...

(http://superman.nu/tales2/chronicles/3/26.gif)

Quote from above scan:

RAO - In the mythology of ancient Krypton, the sun-god, who was deemed the chief of all gods.  So great was the respect for the red sun of Krypton that any soldier of Erok's time automatically became an officer if he had red hair.  When Jaf-El preached the worship of the One god, he gave Him the name of Rao, though no longer identifying Him specifically with the sun.  Note that in the wedding ceremony, the phrase used was "Rao, who kindled the sun," showing Him to be the sun's creator, but not the sun itself.

Note below how Erok, the founder of the House of El, describes Rao as the sun itself in the scan below.

(http://superman.nu/tales2/chronicles/3/23.gif)

If you don't want to accept it that's your business.  But I know I've posted this stuff before re: Rao.

Trying to rationalize the Silver Age Krypton and Superman is ALWAYS a daunting task....

    For instance, Kryptonian MATTER seems to be a little different from normal matter, in the Silver AGe....as soon as it was under a yellow sun, it became invulnerable.

     For instance, the Silver AGe Superman's costume, the rocket, etc.

     My own pseudo-scientific explanation is that the Sun-Beings who created Krypton made the internuclear bonds of the atoms from which they FORMED Krypton dependent on solar radiation---so if Krypton ever becomes a danger,  they could withhold solar radiation and Krypton would disperse into subatomic particles.  A side-benefit of that is that, under the more energetic radiations of a yellow sun, those bonds are made much more powerful---rendering the material invulnerable. (Since the "ultra solar rays" from Earth's sun goes right THROUGH Earth) I have to assume  that they're really talking about neutrinoes---that yellow suns put out a different "flavor" of neutrinoes than red suns, or at least in differing quantities.

    And the relevance to this discussion? That all the elements would be ANALOGS to normal matter elements---sort of how anti-matter "iron" is possible---but might have differing properties. So it really MIGHT be composed most of "uranium", or rather the Kryptonian matter equivelent....which might have different properties from the uranium we know

    Of course, it's all pseudo-science, but it SOUNDS plausible, anyway.---Al

I *do* remember said post that gave Krypton the .24 of the Sun, CaptainKal, I'm curious how your calculation would be affected by the fact that Krypton's core, supposedly, is made of uranium as our buddy Weisenger told us, a particularly dense metal.

(Einstein once said "do not worry about your problems with mathematics, I assure you mine are much greater." Yeah, easy for YOU to say, you're EINSTEIN.  :mrgreen: )

As for the fact that Krypton's metals and materials ALSO became "super," perhaps this may not be a case necessarily, of it being instantly super as a result of being exposed to red sun rays, but the fact that worlds like Krypton and Daxam are so much DENSER than earthlike planets, and so have probably a higher concentration of heavier elements, substances and materials, than can be found on earth. The most common element in the earth's crust is silica; gold is said to be the equivalent on Krypton. Now, in terms of density, silica is 2 1/3 g/cm3, whereas gold is 19.3 g/cm3, a much denser substance by a factor of more than 8:1. In our own earth's formation, the lighter materials rose above the heavier ones. A tougher world probably yields denser and harder substances and materials.

Hey, Julian, I was rethinking your question last night and I believe the higher uranium density of 19.1 g/cm^3 compared with iron's 7.87 g/cm^3 would reduce Krypton's radius from 0.26 to 0.16 or so.

As I said earlier, it's not far from the original figure but it is affected.

I'll think this through in more detail to see what I come up with.

One possible reason for super-matter having different properties under a red sun than under a yellow sun.  Or green sun, orange sun, blue sun, white sun, etc..  Magic.  The energies used for magic exist throughout the DC Multiverse.  Those energies could be generated by the stars.  Maybe those energies come from some other as yet unidentified source & pervade the universe.  According to some stories magic like cosmic rays travels throughout the universe in waves.  Maybe those "waves" interact with stars in some way.  Thus, red-sun rays, ultra-solar rays etc. are not really solar energy, but are different forms of magical energy.


    Yes i am aware that ancient kryptonians associated Rao with their sun.  However in more modern times Rao was kryptonese for God.  I have never seen a silver-age story where modern kryptonians called their sun Rao.  Actually in most stories about krypton, it was never specified what krypton's sun was named.

I like it...magic is present in the DC universe and its an explanation that has some elements of parsimony...

Oh, and I have to admit that I'm not a fan of the Julius Schwartz era, it is my perogative to have likes and dislikes, and that doesn't mean I am denigrating the Silver Age, I was there in the 60s reading comics, and I thought the 70s took the mythos way too seriously...made connections that put DC in an awkward, pseudo science but not really science position...

That's MY story, and I'm sticking with it... 8)

OK, guys, disregard my last muddled post on Krypton's uranium core and the adjustment to its radius.  I made the mistake of starting from the brown dwarf figure when I should just have used the vanilla calculations.

If we maintain the same proportionate density, then to double the gravity means eight times the mass with twice the radius.  Though the planet has 8 x more mass the distance to the core is doubled, and gravity obeys the inverse square law so the relative gravity is reduced by a factor of four.  8 / 4 gives us 2.

Following that same reasoning, a 35 G world with the same density as Earth would have 35 x the radius and 42,875 x the mass.  Clearly, this cannot be so since this would give a planet well beyond the brown dwarf range and it would be a small red dwarf star.  Hence, I adjusted my old figures based on the idea that a brown dwarf would be the max value for a planetary mass.

But we've specified a uranium core that suggests an overall density that's about 2.42 x greater than Earth's. (Uranium density = 19.1 g/cm^3 vs Iron density = 7.87 g/cm^3.)  That reduces the mass by that 2.42 factor to 17,666 x Earth's.

To achieve that 35 G gravity with that mass we divide 17,666 by 35 and take the square root of that.  That gives us a radius factor 22.46 x Earth's.  That's nearly 0.21 x the Sun's radius.

So, a uranium core implies a mass of 17,666 x Earth's, or 0.053 x the Sun's mass, and a radius 0.21 x the Sun's.

I knew intuitively the figures wouldn't be that different but it 's reassuring the math actually works out.

Hey, Gary, when you see this, do the double-check for me, please?  Thanks in advance.

Not to add another layer to what is already a complex problem, but ... ;)

One of the things that jumped out at me in the Krypton Glossary is the fact that eighteen Kryptonian years is equal to 25 Earth years.  Basically, this means that by the time Earth has complete 25 orbits of the sun, Krypton had completed 18 of its primary.

All well and good, but when one takes into account the massive nature of the planet as calculated, one discovers that Krypton is screaming around its primary at a velocity unheard-of for a planet that massive.  By way of comparison, the massive planets of our own solar system orbit their primaries in periods better-measured by Earth decades.

This naturally brings to mind speculation about the distance between Krypton and its primary.  Krypton's primary must have been a red giant, after all -- meaning the star was far more massive than our own G-type yellow sun.  I don't know the math to check this, but I would have to assume that a planet that massive careening around its primary at that speed would have to be an inner planet, otherwise its velocity would overcome the gravitic pull of the primary and send it off into space.

Again, I don't know the math, but since you've calculated both the mass and size of Krypton, it might be interesting to know just how close it would have to be to the primary to keep from flying off into space.

The known factors in the equation are the mass of Krypton and its orbital period (one orbit of the primary every 1.3889 Earth years).  The unknown factor is the mass of Krypton's primary.  One could substitute the mass of a known red giant for Krypton's primary and see where the figures take you.

Dakota Smith

Ah, DakotaSmith, you do know how to pose the tough questions, huh? :)

The figures would vary depending on the star Krypton was orbiting around.

If it were in our solar system, it would have to be 1.24 x as far from the sun than Earth is to have that orbital period.

The mass of the orbiting planet is largely irrelevant assuming the central star is the dominating gravitational partner.  Even for Jupiter and Krypton we can ignore their respective masses in the calculations.  What's important is the star mass and the orbital distance.

But we have to factor in the 'habitable zone' where liquid water could exist on a planet around a star.  I've already figured this out for Krypton in our solar system.  I'll have to ponder this some more for red dwarf and red giant stars to see what boundaries we can put on Krypton's orbit there.  It may be one or the other type of star may not be possible to both have that orbital period and be in the habitable zone.

I'll probably need a day or few days for this.

In the comics krypton's sun was a red giant.  It just strikes me as weird to think that the kryptonians would give their sun the same name as the "creator" of the universe.  I imagine this coming up when Lois (or any other reporter) interviews Kal.  Lois: What did the kryptonians name their sun?  Kal: Rao.  Lois:  Isn't Rao kryptonese for God?  Kal: It is.  Lois:  Why would your people name their sun after God?  Kal:  It's complicated.


     According to Maggin Kal's body has the density of white-dwarf-star-material.  Or something near that.  I imagine that the planet itself would be even denser.  Also keep in mind that super-matter seems to have anti-gravity properties.  Would a core of Uranium augment the heat krypton received from its sun?  If krypton were real, it would be interesting to see what it would really be like.

No it's not, The Romans called Apollo "Phoebus".
Phoebus means Shining-one, it was also used by poets to describe the Sun.

In greco/roman mythology Apollo was not the "creator" of the universe.  Saying that something is weird, is not saying that it can't happen.  In reality people do weird things all the time.

I never said he was, but both Apollo and Rao are Sun Gods.

Heck, most of the planets and moons in our very own solar system are named after Roman gods, least us not forgot! :)

So it would make sense to name their sun after their sun god.

Rao was only the name of a sun-god in ancient times.  When kryptonians became monotheistic Rao became their name for the creator of the universe; iow God.  In the silver-age (at least) krypton seemed a lot like an idealized Israel.  After Jaf-El's time Rao became kryptonese for God.


    Krypton should have had many civilizations & cultures coexisting.  At least in ancient times.  Kryptonians should have had many religions & mythologies.  Which means many pantheons of mythological gods.  Rao should have been only one of many sun-gods.  That kryptonian civilization would be so relatively homogenized almost from the beginning, weird.  Funny thing is the writers seemed to be of two minds about krypton's size.  On the one hand; they established that krypton's size was somewhere between 5xearth & jupiter. Otoh; most of their maps, geographies, & histories seem better suited for an earth-size planet. :roll:   That thing about 18 kryptonian years equalling 25 earth years also seems more suited for an earth-size planet.  Seems the writers (& editors) never imagined that krypton as a giant planet has more ramifications than just super-gravity. :twisted:

Is it any less weird that we humans generally refer to the name of our planet as Earth, the same name that we would label some lesser plot of land (but usually without a capital "E")?

I agree, let's rename it "Hooston."

:s:

The problem I discovered when figuring out Krypton's orbit for DakotaSmith was that 25:18 Earth year:Krypton year ratio pretty much made it very difficult if not outright impossible for me to put the planet in a habitable zone around any normal red star -- red dwarf or red giant.

It actually came closest with a red dwarf star verging on an orange dwarf at 0.33 solar masses and an orbit about 0.86 of our own distance from our sun.  But that would give a very feeble 2.7% of the solar energy that our own world receives from our sun.  If we took a red giant then we get the opposite problem that an orbit consistent with that year ratio give a planet that should have its oceans and atmosphere burned off by being too close to that darned red giant sun.  If we accept the red dwarf option, then not only were Kryptonians exposed to solar radiation that had an overall lower energy spectrum, but the actual intensity was a tiny fraction of ours.  The difference in solar energy coming to our world would be a lot more dramatic than just exchanging a red lamp for a yellow one.

One compromise is that the red dwarf figures I gave are augmented in three ways.  Krypton had a higher carbon dioxide content in its atmosphere hence having a much more pronounced greenhouse effect.  Al Schroeder speculated as much in one of his internet articles (though until now I really leaned towards the red giant option).  This is consistent with Krypton's red sky (carbon dioxide scatters red light more giving mars a red sky) and "The Sun of Superman" story where we learn without Krypton artificially affecting their sun that its natural state is an orange dwarf star.  The other factor is Krypton's own internal heat from that natural uranium reactor in its core was helping keep the temperature habitable on the planet surface.  Krypton was almost a failed star afterall and it likely had a lot of trapped heat from planetary formation and fizzled fusion reactions.

Another option is their sun was still a red giant star but the artificial presence of the Sun-Thrivers feeding on that solar energy reduced the output sufficiently to let Krypton hold onto its water and air.  For a 2 solar mass red giant star Krypton's orbit would be 1.56 x ours from our sun, FYI.

Thoughts?

(Oh, BTW, if anyone wants, I can post the calculations and formula this is based on so they can play with it to see what other possibilities they can come up with.)

Okay, so I'm somewhat slower than a speeding bullet.... :)



So far so good....



The Earth's not solid iron, and has a density of 5.515 g/cm^2 according to Wiki, but I think you're assuming that the other stuff has the same density ratio as well.



Here's where I had a problem with this. Your mass calculation above was based on the premise that you were changing the mass but not the radius.  If you now change the radius, the mass is going to change proportionally, and you don't have 35x Earth gravity any more.

Or something. Actually, I'm kinda scratching my head trying to figure out what you did here. So I'll just tell you how I would answer this, and maybe you can figure out where we disagree.

The gravitational attraction of a planet is proportional to (mass) / (radius) ^ 2. Since the mass goes like (density) x (radius) ^ 3, in terms of density and radius the gravitational attraction is proportional to (density) x (radius).

This is why, as any college physics teacher will tell you, it's better to do algebra and not put in actual numbers until the very end. :)

Anyway, you want an overall ratio of 35 for the gravitational attraction. The densities are in a ratio of 2.42. So you would need the radii in a ratio of 35 / 2.42 ~= 14.5. Krypton would need a radius of 14.5 Earths, or about 0.13 Suns.

Here's a possibility concerning the destruction of Krypton, and why it was so catastrophic:

Earth, with its comparatively low gravity, has almost none of the lighter gases, which when heated achieve escape velocity from earth. This accounts for why Helium was found on the sun before it was discovered on the earth, but why gas giant planets, like Jupiter, with far greater gravity than our planet, have helium and hydrogen in their atmospheres. Krypton, with its far greater gravity, might be able to keep on to these kinds of "light" gases.

Thus, explosions would be far more destructive on Krypton than on earth, as they would cause the hydrogen in the atmosphere to ignite.