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View Full Version : Where can I find online gas giant generator ?



orinetz
2009-Apr-08, 02:09 AM
Hi, everyone

I am Fendy a new member here. At the moment I am looking for online tools for generating images for gas giant type planets for my klemperer rosette computational experiment (http://orinetz.com/planet/animatesystem.php?ephid=F4YFA49QGIJGYSAHCIFQ4JH1S0 0001).

So far I just found the one for generating terrestrial type planet in eldritch.com (http://www.eldritch.org/erskin/roleplaying/planet.php)

If someone know where to look for it, please tell me. If not I plan to make one in my own web later.


Thank you,

Fendy

HenrikOlsen
2009-Apr-08, 10:56 PM
How can you have a Klemperer rosette with an odd number of orbiting objects?

If you read his original paper (http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1962AJ.....67..162K) you'll see that they are specifically even numbered, it says so right in the second sentence of the abstract:)

mike alexander
2009-Apr-09, 01:49 AM
A guess; orinetz is modeling the rosette of Puppeteer worlds from Niven's Ringworld. Since the Puppeteers had the technology to move and set in motion a five-membered rosette (using the Outsider's reactionless drive) in the first place, they could probably damp out any emergent instabilities as they arose.

tdvance
2009-Apr-10, 12:15 AM
If it's just images--there's a Gimp tutorial on drawing space scenes with gas giants.

http://www.solarvoyager.com/images/tutorials/gasgiant.jpg

Note this tutorial "document" is a jpeg image--on my Firefox, I do have to hit the "zoom" to undo its automatic "fit big jpeg into smaller window so it can't be read" habit. Alternatively, save it to disk and use, say, Gimp to zoom in on the text!

Still, I've followed this one before, it's reasonably straightforward and gives pretty good results. Actually, it might be written for Photoshop, can't remember, but it worked in Gimp for me.

tdvance
2009-Apr-10, 12:18 AM
A guess; orinetz is modeling the rosette of Puppeteer worlds from Niven's Ringworld. Since the Puppeteers had the technology to move and set in motion a five-membered rosette (using the Outsider's reactionless drive) in the first place, they could probably damp out any emergent instabilities as they arose.

Actually, it was 7 planets, sun in center. Perhaps the sun in the center makes a difference? The Puppeteer worlds were 6 with no sun, then later 5 with no sun when those darn humans made off with one of the planets....

orinetz
2009-Apr-10, 03:31 AM
How can you have a Klemperer rosette with an odd number of orbiting objects?

If you read his original paper (http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1962AJ.....67..162K) you'll see that they are specifically even numbered, it says so right in the second sentence of the abstract:)

Good Question. This question had been asked in other forum as well. The answer is if you want alternating m1,m2 body, your planetary system will indeed have to consists of even numbered orbiting body.

When we are talking about stability and instability in n-body simulation, there could be more than one kind of stability. The purpose of that simulation is to find out what kind of instability Klemperer rosette with odd number of orbiting objects are going to exhibit.

This is of course assuming that no other object without the same rosette configuration is going to disturb the stability.

With said assumption in place, for objects with equal mass, I suspect that the reason of instability observed in Odd-Bodies Klemperer Rosette (lets call this OBKR) simulation is somehow unphysical. Here is my explanation:

Klemperer Rosette is in itself is an unstable arrangement due to the fact that gravity get stronger as you get nearer and weaker as you get farther from a body with mass. As such a little discrepancy from the perfect polygonal arrangement is going to grow into big one over time. This is true for both Even-Bodies Klemperer Rosette and OBKR.

This perfect polygonal arrangement pose a serious problem due to the nature of how we represent floating-point vector in binary format. No matter what you do we never get an irrational number (and sin(2*Pi/N) value for odd-N are usually irrational numbers) represented in unlimited accuracy. This is going to be the cause of the little discrepancy that later going to grow bigger and bigger.

As long as we use floating-point-vector based simulator, we are going to observe non-polygonal instability occurring in OBKR. If instead we use simulator specialized to run klemperer rosette, we could see that the OBKR is stable for infinite period of time. Or if there are more than one set of Klemperer Rosette, the system could show polygonal instability instead of non-polygonal instability.

In reality however, a klemperer rosette would always require active maintenance from the civilization creating it. If for one or many reason the civilization collapse, the alien visiting said civilization millions years later is going to find the klemperer rosette evolve into something else.

HenrikOlsen
2009-Apr-13, 03:31 PM
Actually my point is that the setting with only one size of orbiting masses is not a Klemperer Rosette and calling it that is perpetuating the second error Niven made about them. (The first was calling him Kemplerer)