Antarctic Space Nazis Across the Multiverse

[tshiggins]

Originally Posted by Icelander

(SNIP)

What ought the salient feature of ASN underground defenses be, in case the PCs try to be sneaky and subtle?

Well, the Germans did invent Bouncing Betties.

https://en.m.wikipedia.org/wiki/S-mine

[Icelander]

Originally Posted by tshiggins

Well, the.Germans did invent Bouncing Betties.

https://en.m.wikipedia.org/wiki/S-mine

Indeed.

But if you just place them on the ice, won't they be incredibly obvious?

Whereas if you conceal them under ice, they will be prevented from bouncing, which makes them less effective.

Directional anti-personnel mines can be concealed in icy tunnel walls or under an inch or two of re-frozen ice under potential intruders, without losing much, if any, of their effectiveness.

Of course, a TL5^ Fougasse could be built in place into the ice, using iron projectiles and black powder propellant. Use a minor Conditional cantrip of a brief flame to trigger it and you've got a pretty cheap, but reliable mine, as long as you have the magical ability to make the ritual trigger.

Unfortunately, while the occultists of the Ahnenerbe are providing lots of magical support, they are not going to be living in Kadath, let alone patroling ice tunnels below it. A squad of Aghartan combat engineers from Svartálfrheim, specialized in tunnel warfare, might include a trapsmith with minor sorcerous abilities, but somehow I doubt such a guy would want to stay there.

So, whether the magical triggers were made specific enough and long-lasting enough to use without an assigned occultist, or the ASNs would give their allies something to convince them to assign a sorcerous demolition expert to Kadath on a permanent basis, I guess a magical solution would cost at least what a more mundane, technological solution would cost.

And that would probably be a design of landmine known to German engineers who left Earth for good at the end of WWII, either triggered by a typical mine detonator or command detonated by a nearby soldier by pulling a wire, as the first step of an ambush.

Kadavergehorsham stormtroopers can be assigned to permanent sentry posts, with occasional patrols, and they ought to be able to handle pulling a wire, as long as they are allowed to charge afterwards.

[Icelander]

While Germania Hyperborea is not Earth, as any astronomer can determine, it is a close enough mimicry to have a moon that matches Earth's in orbit. The external signs of orbiting the sun also seem identical, i.e. seasons and climate by location on the planet, length of days, etc.

It might thus occur to bright historians and/or students of astronomy among the ASNs to look for local records of solar and lunar eclipses, partial or total, and compare them with the state of the art of their 1945 calculations of the dating of historical eclipses.

Does anyone happen to know how precise these calculations were in 1945? I can find evidence that even at the end of the 20th century, historians and astronomers disagreed fiercely on the dating on given astrological phenomena and what signs would have been visible to people on the ground.

How close to our 2010s dating of historical eclipses would the ASNs be if they had taken copies of the state of the art in astronomy textbooks and theories in the 1940s, but made no special efforts to recruit practising astronomers?

[johndallman]

Originally Posted by Icelander

I can find evidence that even at the end of the 20th century, historians and astronomers disagreed fiercely on the dating on given astrological phenomena and what signs would have been visible to people on the ground.

There is some weirdness in your usage of English "astronomy" and "astrology." Can you give examples of what you're considering examples of each?

[Icelander]

Originally Posted by johndallman

There is some weirdness in your usage of English "astronomy" and "astrology." Can you give examples of what you're considering examples of each?

Sorry, it would have been clearer to use 'astronomy' across the board, there. I was imprecise in that the people who historically recorded the eclipses would have been practising Astrology, but the 1940s calculations on dating historical eclipses would be Astronomy, and so that is the terminology I should have gone with.

'Astrology' is meant to refer to the historical mixture of observational astronomy and pseudoscience that is to Astronomy skill as Esoteric Medicine is to Physician.

Basically, I'm asking about the ability of the ASNs to date Germania Hyperborea, at least as a mimicry of Earth, by comparing Earth calculations for historical eclipses, derived using Astronomy/TL7 (early), to local records of eclipses or other celestial phenomena observed and recorded using Astrology/TL1+.

[johndallman]

Originally Posted by Icelander

Does anyone happen to know how precise these calculations were in 1945? I can find evidence that even at the end of the 20th century, historians and astronomers disagreed fiercely on the dating on given astronomical phenomena . . .

The main cause of that is imprecise historical descriptions of the positions of celestial bodies, plus things like accounts of total solar eclipses taking place at combinations of places and times when they definitely didn't.

The biblical accounts of darkness at the time of the crucifixion are often interpreted as a solar eclipse, but it was known at the time that this could not have been the case: solar eclipses can only happen at the new moon, and Passover can only happen at a full moon.

As regards calibration, did the ASN think to bring high-quality chronometers with them? Or are they finding that Germania Hyperborea's rotation period is the same as Earth's to within the limited precision with which they can measure it, and assuming that it is actually the same?

If the latter applies, they'll use it to calibrate their clocks, and then they can try to locate themselves in time by finding the planets in the sky, getting their positions reasonably accurately and extrapolating their movements backwards from the orbital information for Earth. There are margins of error in that orbital information, but within a few months of observations, they'll be able to locate themselves to the day if they're within -10k to +10k years. Or know that they aren't in that range, or if the periods of any planets are significantly different, that this is not Earth.

It gets slowly vaguer outside that kind of range, as margins of error accumulate, and once you get to tens of millions of years, you can't date anything, because mutual perturbations make the positions of the planets along their orbits unpredictable on that timescale.

[Icelander]

Originally Posted by johndallman

The main cause of that is imprecise historical descriptions of the positions of celestial bodies, plus things like accounts of total solar eclipses taking place at combinations of places and times when they definitely didn't.

The biblical accounts of darkness at the time of the crucifixion are often interpreted as a solar eclipse, but it was known at the time that this could not have been the case: solar eclipses can only happen at the new moon, and Passover can only happen at a full moon.

Indeed.

I take it that this means the ASNs would have pretty good calculations on when eclipses should occur on a planet matching Earth, but may have difficulty reconciling this with ancient systems for measuring time or the precise dating of historical events?

But is the discrepancy between calculated dates of historical eclipses from astronomy and possible historical events that might coincide with them likely to be a matter of days, months, years, decades or centuries, when trying to fix a specific era that corresponds with some time in the first millenium BCE?

Originally Posted by johndallman

As regards calibration, did the ASN think to bring high-quality chronometers with them? Or are they finding that Germania Hyperborea's rotation period is the same as Earth's to within the limited precision with which they can measure it, and assuming that it is actually the same?

Yes to both.

They have naval chronographs (certified as chronometers and possibly some equipment to perform tbeir own certifiactions) for navigation and to the precision they can measure, the rotational periods are identical.

Originally Posted by johndallman

If the latter applies, they'll use it to calibrate their clocks, and then they can try to locate themselves in time by finding the planets in the sky, getting their positions reasonably accurately and extrapolating their movements backwards from the orbital information for Earth. There are margins of error in that orbital information, but within a few months of observations, they'll be able to locate themselves to the day if they're within -10k to +10k years. Or know that they aren't in that range, or if the periods of any planets are significantly different, that this is not Earth.

It gets slowly vaguer outside that kind of range, as margins of error accumulate, and once you get to tens of millions of years, you can't date anything, because mutual perturbations make the positions of the planets along their orbits unpredictable on that timescale.

Yeah, this is one of the parts that doesn't work, as the position of the planets, while individually fairly plausible, is not in line with any Earth date when considered as a whole.

Which is why I thought of eclipses, as even if the stars and even planets are different (or even don't exist except as glamour), the moon seems to be real or at least close enough so that it might cover the sun at the same time in this place as on Earth.

So, even if Germania Hyperborea is not Earth, learning if it has any recorded eclipses before the ASNs arrived that might correspond with historical eclipses could narrow down the point in historical time which Germania Hyperborea is meant to represent... if any.

The ASNs have seen no eclipse in the fifty years they've been there, but if there are astrologers among the native cultures, it's plausible that they'd have some form of record of any that might have occurred within their collective cultural memory.

[johndallman]

Originally Posted by Icelander

I take it that this means the ASNs would have pretty good calculations on when eclipses should occur on a planet matching Earth, but may have difficulty reconciling this with ancient systems for measuring time or the precise dating of historical events?

Solar eclipses are used as calibration points for figuring out historical calendars. Those tend to work on things like "In the tenth year of King Foo, after he had married Bar of Egypt. . ." but they often mention eclipses. Since a solar eclipse is only total over a long narrow strip of Earth's surface, whose position can be precisely calculated, a total eclipse is much more spectacular than a partial one, and it's often easier to know where historical events took place than when, eclipse calculations are considered far more trustworthy than adding up years in ancient records.

The ASN will be able to develop the capability to do these calculations. The mathematics is not trivial, but they have textbooks.

But is the discrepancy between calculated dates of historical eclipses from astronomy and possible historical events that might coincide with them likely to be a matter of days, months, years, decades or centuries, when trying to fix a specific era that corresponds with some time in the first millenium BCE?

Solar eclipse calculations can readily be accurate to a minute and a mile. If the historical records are both trustworthy and incompatible with the eclipse calculations, then something's wrong. It's easy to assume that someone dropped a year, or a few days, in a historical record.

So, even if Germania Hyperborea is not Earth, learning if it has any recorded eclipses before the ASNs arrived that might correspond with historical eclipses could narrow down the point in historical time which Germania Hyperborea is meant to represent... if any.

This works better the closer you are in time to the event, and the more precisely you can place the location.

The ASNs have seen no eclipse in the fifty years they've been there, but if there are astrologers among the native cultures, it's plausible that they'd have some form of record of any that might have occurred within their collective cultural memory.

Indeed, but there is a kind of eclipse that the ASN will have seen several of, and that's lunar eclipses. Now, those are visible over a much large area, and are much less spectacular. However, the ASN can determine their latitude on GH quite precisely by astronomical observations, and can determine the Moon's orbit fairly accurately in the same way. With those, and the intervals between the lunar eclipses they've seen, they can start to eliminate periods of history within the first millennium BCE. They can compare those results with the timing of predicted solar eclipses and iterate towards a date.

[Icelander]

Originally Posted by johndallman

Solar eclipses are used as calibration points for figuring out historical calendars. Those tend to work on things like "In the tenth year of King Foo, after he had married Bar of Egypt. . ." but they often mention eclipses. Since a solar eclipse is only total over a long narrow strip of Earth's surface, whose position can be precisely calculated, a total eclipse is much more spectacular than a partial one, and it's often easier to know where historical events took place than when, eclipse calculations are considered far more trustworthy than adding up years in ancient records.

The ASN will be able to develop the capability to do these calculations. The mathematics is not trivial, but they have textbooks.

Solar eclipse calculations can readily be accurate to a minute and a mile. If the historical records are both trustworthy and incompatible with the eclipse calculations, then something's wrong. It's easy to assume that someone dropped a year, or a few days, in a historical record.

This works better the closer you are in time to the event, and the more precisely you can place the location.

Indeed, but there is a kind of eclipse that the ASN will have seen several of, and that's lunar eclipses. Now, those are visible over a much large area, and are much less spectacular. However, the ASN can determine their latitude on GH quite precisely by astronomical observations, and can determine the Moon's orbit fairly accurately in the same way. With those, and the intervals between the lunar eclipses they've seen, they can start to eliminate periods of history within the first millennium BCE. They can compare those results with the timing of predicted solar eclipses and iterate towards a date.

Ah, excellent. And when they have a working hypothesis, they can send expeditions to places where an eclipse is predicted, to confirm or refute.

Which ought, at the very latest by Year 42, have given them a match between two partial eclipses visible in the analogues to Norway and Russia by the border with Finland in 504 BCE. As part of their arctic exploration, I expect they could have built an airship base in Norway in time for the February eclipse and then travelled by airship to see the July eclipse to the east.

This would have been as the new generation of Elemental Furnace powered rigid airships were being trialed, finally having enough power and thrust for lengthy expeditions without ground support and only supplies for the crew limiting the airship range.

So, local time in Germania Hyperborea is 495 BCE. Which, of course, makes no sense, as there is not even the semblence of a Persian empire, Greek civilization, Rome or a multitude of other things which indubitably belong to that time in history on Earth.

Not to mention that individual artists and craftsmen among pseudo-Celts seem to be making items every bit as materially advanced as examples identified with La Téne, sometimes even arguably better, and the art is undeniably remniscient of La Téne (which should not even exist yet, let alone be fairly widely distributed). There are also societies influenced by the Minoan/Pelasgian religious caste which have a material culture inconsistent with such an early date, in that their metallurgy, smithing and general craftsmanship is in no way inferior to medieval archaelogical remains.

Architecture and social organization, however, seems broadly in line with 6th or 5th century BCE, perhaps even a bit earlier. A lot of tribal societies, kinship-based groups and generally small polities. No lack of trade or travel, but a conspicious lack of vast empires. The largest polities seem to be city-states or tribal confederations, depending on whether we measure by population or territory.

Well, the Rasna, in where Italy should be, are some form of allegiance between city-states, and various city-states in the eastern Mediterranean and Black Sea have allegiances with local tribal confederations (usually against others), but these hardly seem close enough to warrant being considered unified as one polity.

[johndallman]

Originally Posted by Icelander

So, local time in Germania Hyperborea is 495 BCE. Which, of course, makes no sense, as there is not even the semblence of a Persian empire, Greek civilization, Rome or a multitude of other things which indubitably belong to that time in history on Earth.

There are doubtless explanations for that.

However, I forgot something simple which would give an approximate date much sooner: the precession of Earth's axis. There is an important starting point in the sky for both astrology and astronomy, the First Point of Aries, which moves slowly through the sky, going round it in about 25,772 years. Locating it takes some care with positional measurements over a few months, but is not difficult: it was defined by Hipparchus in 130 BCE.

The ASN astrologers would have been keen to get this kind of basic measurement done early on, so that they could cast horoscopes properly. I can see several possible answers:

• It's consistent with the eclipse-based date.
• It's exactly where Hipparchus placed it, and does not move.
• it's where it was in April 1945, plus time passed since then.

It will doubtless occur to someone to cast a horoscope for someone "born" at the Externsteine at the time the first ASN explorers appeared there in Germania Hyperborea.