A friend and I set ourselves the question: what if mankind knew that it would slowly and inevitably die out. What monument could we build that would be most enduring and obvious that once a civilization existed?

We agreed that it would have to incorporate knowledge of the primes and the transcendental numbers. It would have to be large enough to seen from space and to survive erosion over millions, possibly tens of millions of years. My friend suggested it be built at the equator to avoid being covered by polar ice. I suggested that latitude would be the only way of incorporating e and pi into the monument. It would have to be of a shape not naturally occurring in nature. For want of better we decided on pyramids.

We finally came up with a ring of 6 groups of pyramids at latitude arctan(e/pi) = 40.87 degrees, equally spaced in latitude. Each group would have a prime number of pyramids: 2, 3, 5, 7, 11, 13.

I then found this site which is debunking the 'face on Mars' site: The Enterprise Mission, run by Richard Hoagland. I agree that Hoagland’s city of angles relies on mathematical co-incidences, but I am surprised that his "D&M pyramid" has some relation to me and my friends proposal in that the latitude is 40.87 degrees.

Constructing these pyramids would be a huge effort for a dying civilization and surely there must be a better and cheaper way of doing things than what 2 friends can come up with in an evening.

Seeing as this bulletin board has many scientifically trained members, you and other intelligences have probably come up against this problem and solved it better.

I would be interested to hear of this solution and, if you are concerned about debunking Hoagland, it would be sensible to make this solution known. Put simply, you will be able to say “Why would an alien civilization bother to build a giant pyramid at arctan(e/pi) when it all could have been done so much more cheaply.”

I'm sorry I can't offer a prize for the best solution.

Regards

John

Welcome to BABB.

Degrees? What kind of a mentally-challenged civilization would use degrees for angular measurement, these little arbitrary angles, 360 of which fit into 2*pi radians, a circle?

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I think that a truly intelligent species would sculpt an enormous set of buttocks on the surface of Ganymede, the largest moon in the solar system, as it were....

It is not that the angle is 40.87 degrees or 45.41 grads or 0.7133 radians (which it is), but that the tangent of this angle equals e/pi. Of course the question could also be asked, "why the tangent?" since e/pi is less than one and so the sine or cosine could just as easily have been used.

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The bar has been lowered for the promotion of ATM ideas; the bar for the acceptance of ATM ideas must remain high.

Welcome aboard, hammo1j. =D>

I am not very good on this stuff but I'm taking a lunch break.

The "e/pi" issue seems superfluous to me. The prime numbers alone does the trick in my book. Also, their value of pi could be 2pi, assuming they prefer to work with radii in lieu of diameters.

The pyramid location might be more an issue of "low overall bid" and not a specific lattitude. Then there is the issue as to what message they want to convey. Pyramids are poor representations of advanced civilizations (Vegas not withstanding).

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Here we go folks - just looking at one of your signatures gave me this idea

.11011101111101111111011111111111 in base 2 = prime number encoding = .8670649526175111 in base 10

Get the arctan and we have 40.92 degrees just a little bit north of the pyramid 40.87 and south of the face 41.185 degrees. Shows how easy it is even for an amateur like me to come up with results.

Interestingly in reply to a previous post, arcsin and arccos don't work as well because they produce results very close to 60 and 30 degrees and the obvious ratio is 1/2. arctan does tend to suggest an orthogonal co-ordinate system as well.

Hey fellas I thought we were supposed to be coming up with stuff to beat my crappy pyramids. Come up with something better or I will set up a website asking for contributions to build mankind's own monuments...

Just a question: what about the continental drift? In some tens millions years your pyramids will move significantly from 40.87 degrees...

I think that if we want to leave some traces we should build something on the moon (not geological active and not too much erosion also) or better place it in one of the stable Lagrange point of Earth-Moon system. Its artificial origin will be obvious. Still we should point somehow that the thing was placed there by earthlings...


Edited for spelling.

that was my thought, too, Baloo, since the science I know best is geology.

and yes, welcome.

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Gillian

"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"

"You can't erase icing."

"I can't believe it doesn't work! I found it on the internet, man!"

When pyramids erode (after more than tens of millions of years) they look like hills. I suggest building a wall with a 1*1 KM cross section, in the shape of "HELLO" with the face of Lionel Richie carved next to it

Seriously, I don't know what would be clear after a long amount of time. lakes can be flooded, wiping their form out. Objects erode or get grown over by plants. So we'd have to build something really big and really clearly artificial. And add a "the only purpose of this thing is being visible, don't attach any lousy explanations as to itss possible uses please" plate to it, just in case. Shapes, let's see. Something round can be a crater. A pyramid can be hill. I suggest something like a square spiral wall of huge dimensions. One could add extra hints, like placing respectively 1, 2 ,3 and 4 identical towers (not tot high so they are really strong) on the sides.
Plus a huge "NO PRACTICAL USE WHATSOEVER" sign, don't forget.

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To the regular visitor of internet bulletin boards it is clear that it's an excellent idea your parents get to choose your real name.

If you're really stuck on pyramids, try putting 4 triangular pyramids equally spaced, so that they form the corners of a tetrahedron just slightly larger than the planet.

It's not my idea. I read about an artist doing it, or at least contemplating it, long ago. Oops. I forgot that Google is my friend. It is described here.

Do that, only bigger. For redundancy, and if you have the budget, do a dodecahedron. Then you can still lose some of the corners and the remaining ones will still cry out.

But, plate tectonics will still drag them out of position, and the environment will tear them down.

Edit:

Nah, use .41235... That would be a sign of real intelligence. Imagine, a transcendental number that in its infinite binary expansion (.0110100110010110...) never repeats any string of bits 3 times in a row. How sublime. Much cooler than e and pi.

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I say we make a giant can of Spam, about the size of New York, and in the center place the entire DvD collection of Monty Python's Flying Circus.

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"There is no problem that cannot be solved by a suitable application of high explosives" - US Army Demolitions School

http://worldsofothersuns.home.comcast.net/

Winner!

No..no..no...what we need is a giant solar powered beacon that perpetually broadcasts Beavus and Butthead episodes over and over again.

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Anything may be possible, but not everything actually is. Some things are true and some things are not. Wisdom is knowing the difference.

What if we spread a zillion plastic ducks over the ocean? UV degradation would be a show stopper, project cancelled. Sorry. SHould have thought about that first.

(seriously, with so many identical lifeless objects, they might think they are naturally formed. All those efforts, for nothing! )

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To the regular visitor of internet bulletin boards it is clear that it's an excellent idea your parents get to choose your real name.

I hate to say it but pyramids are starting to sound less dorky by the post! :wink: Rubber ducks? heh .. why not "faces?" :P

I think Baloo had the best concept if we wanted to preserve our heritage --> off-world.

I second the idea of building it on the moon. Also, whatever we create should be made out of a man-made material that is not naturally present on Earth, perhaps something that takes a lot of technological sophistication to make.

Taking a cue from the survivability of newly hatched turtles, instead of building large monumental pyramids, encode whatever intelligent messages you want in billions of tiny spheres and scatter them around the planet. No matter what happens over eons or time, some will survive, perhaps to be discovered by others later.

Nicolas wrote:
Chip wrote:
The problem with this approach is that a little change in Earth ecosystem could destroy everything: imagine that, since those little spheres are so many, some bacteria will adapt to use them as food. Or some sharks will adapt to eat rubber ducks (well, maybe not sharks, but some algae could do it).

So I suggest to add a little capability to those ducks that they could reproduce (oh, wait...we already have ducks that are doing that ).
Anyway, if we could build billions of robots that could reproduce themselves (adapting to environmentally changes) maybe they could make it for millions years (after all that's how the life has evolved). We should take care that they're multiplying rate is not too big but no too low also. The main problem is that it won't be clear if those who made the robots where earthlings or some other species that, passing by our solar system, decided to do a little experiment. Maybe we could program the robots to keep recordings with Earth's history.

I believe this was already addressed by the Great Star Trek. Ok, it wasn't Earth but ditto TOS.

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You're a coward and a liar and a thOOF - Bart Sibrel

Combined plan for leaving your mark on the solar system:

The mark should be left on a world that is geologically dead, with no significant erosional processes, and no possibility of indigenous life. At the same time it should be either interesting in its own right, or located closely enough to an interesting or possibly life-bearing target in the solar system that an exploring species will take a look at it. Mars is a poor choice, it's not quite geologically dead and has active erosional processes. Earth and Venus are right out, their surfaces are constantly being eroded and Venus's is hidden from direct view. Mercury is energetically inconvienent to visit. Earth's moon is probably the best choice - geolocially dead, no life and little erosion, and close to a likely target of interest. An airless moon of Jupiter or Saturn would also be a possibility.

You will want to leave markings on the target world that will be obviously artificial and visible from orbit. Place identical monuments equally spaced in a three dimensional pattern on the world's surface. There should be enough of them so that a recognizably artificial pattern remains even if some are destroyed by meteor hits, earthquake, or erosion. Twelve or twenty monuments spaced at the points of a regular polyhedron around the world should do nicely. The monuments should be a shape recognizably artificial even after damage and erosion. A pyramid is not a good choice as it can resemble a normal mountain, especially if damaged. A mound in a spiral shape will be recognizably artificial even if partially oblitherated. The material for the mound shouldn't need to be anything more than surface material pushed into shape.

Inside each monument embed millions of identical message capsules. The message capsules should be durable and radiation-resistant, and encoded with information in a way that is fairly obvious and easy to read. Metal plates engraved with microscopic symbol language, or patterns of etched pits, would be one way to do it.

Depending on the desity of the encoding, size of the plates, and your goals for the project, the message capsules can be encoded with anything from a simple "We wuz here" message to the entire contents of the encyclopedia galactica.