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'Mathematically perfect' star system being investigated for potential alien tech

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Re: 'Mathematically perfect' star system being investigated for potential alien tech

#201
post #47

Earlier quoted context omitted.

As detailed in the companion article [1], for every 54 orbits of planet 1, planets 2..6 orbit 36, 24, 16, 12, and 8 times respectively, giving successive ratios of 2/3, 2/3, 2/3, 3/4 and 3/4. After those 54 planet 1 orbits, all planets are in the same relative position. [1] https://www.space.com/six-sub-neptunes-found-100-light-years...

If a K1.5 wanted to do that just for shits and giggles, is there a viable way to slow down or speed up orbits of rocky planets? Like, wouldn't they be shooting a bunch of mass out of their system to even attempt this? If one could build a Dyson sphere, is that more difficult or less difficult than engineering a system like this? The sphere/swarm has some absurd amount of mass all in a very uniform orbit around the su…

There's some principle that for a chaotic system, if the accuracy with which you can measure it is smaller than the largest perturbations you can make to it, you are willing to wait many Lyapunov times, and you have enough compute; then you can control the system. With this after a few dozens of millions of years you could control the small bodies of the solar system using relatively small thrusters and a big radar installation, and then put them all on aldrin cycler orbits to move momentum between the larger bodies.

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#202
post #47
post #17

What is the "mathematically perfect" aspect of this system? I don't see it in the article.

As detailed in the companion article [1], for every 54 orbits of planet 1, planets 2..6 orbit 36, 24, 16, 12, and 8 times respectively, giving successive ratios of 2/3, 2/3, 2/3, 3/4 and 3/4. After those 54 planet 1 orbits, all planets are in the same relative position. [1] https://www.space.com/six-sub-neptunes-found-100-light-years...

Neat. Is this something that tends to happen if there are large planets close to the star? In our solar system, the inner planets are small and the big outer planets are too far out to affect each other much.

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#203

Earlier quoted context omitted.

What is the mechanism by which orbiting bodies exchange energy?

Gravitational waves.

Gravitational waves from planets are undetectably small. They do it through gravity directly, as sandworm101 says. You can model it with pure Newtonian gravity and get resonance effects just fine.

See for instance: https://www.youtube.com/watch?v=Qyn64b4LNJ0

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#204

Reminds me of Titius–Bode law[1], where simple equation correctly gave orbits of all the known planets, while predicting one more in asteroid belt and correct distance to Uranus. Only was considered disproven when Neptune didn't work. I would not trust these relations even existing (other than by pure chance). Even less I'd trust any intelligent design behind it [1] https://en.wikipedia.org/wiki/Titius%E2%80%93Bode_l…

> other than by pure chance Barring intelligent design, there's an extremely good chance that at least one of these systems exist, and an equally good chance that only one exists, and we're just lucky enough to have observed it.

[dead]

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#205
post #97

Earlier quoted context omitted.

I’m not sure I want to meet the alien species that can arrange a star system into a prime sequence.

Especially if the universe really is a dark forest. Although, if you wanted to stay undetected, why would you advertise your solar system like this?

honeypot

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#206

I think the authors do not understand how planetary resonances work and how precise (or imprecise) the orbits need to be for the resonance to hold. Resonances are very common. We have lots of resonances in our Solar system in all different places between bodies. For the resonance to be stable, two bodies do not need to have mathematically precise orbits in relation to each other. There is quite a wide margin for erro…

>HD 110067 (TIC 347332255) is a bright K0-type star with a mass about 80% that of the Sun, located at 12h39m21fs50, 20°01'40farcs0 (J2000). Breakthrough Listen (BL) is observing additional targets selected from the Exoplanet Follow-up Observing Program for TESS (ExoFOP-TESS) in addition to the nearby star sample described by Isaacson et al. (2017). HD 110067 is valuable as a technosignature target not only because of its interest for biosignature searches. First, Earth views the system edge-on, which increases the likelihood of detecting radiation from any transmitters present whether intentional (Traas et al. 2021) or resulting from planet-to-planet transmissions which could be observed by their "spillover" during planet–planet occultations (Ashtari 2023); second, the large number of planets regardless of their position in the star's habitable zone increases the likelihood that an advanced civilization could have spread technology to neighboring planets, as has happened in our own solar system (Wright et al. 2022).

https://iopscience.iop.org/article/10.3847/2515-5172/ad235f

Nobody is suggesting the resonances are unnatural. The edge on aspect helps the search in other ways.

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#207
post #191

Earlier quoted context omitted.

Isn’t that the expected outcome when energy production eventually outpaces the planet’s ability to dissipate energy into space?

No. The temperature of the atmosphere has nothing to do with whether or not aliens are harvesting the energy. At equilibrium, all of the incoming energy has to get radiated back out into space eventually whether there are aliens harvesting that energy or not. The problem with an atmosphere hotter than lava is that very few materials are solid at those temperatures, and it's hard to imagine how a civilization could bu…

Secondarily, thermodynamics and other effects make many processes much less efficient at higher temperatures, examples including engines and solar panels.

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#208
post #191

Earlier quoted context omitted.

Isn’t that the expected outcome when energy production eventually outpaces the planet’s ability to dissipate energy into space?

No. The temperature of the atmosphere has nothing to do with whether or not aliens are harvesting the energy. At equilibrium, all of the incoming energy has to get radiated back out into space eventually whether there are aliens harvesting that energy or not. The problem with an atmosphere hotter than lava is that very few materials are solid at those temperatures, and it's hard to imagine how a civilization could bu…

Sure, energy in equals energy out at equilibrium, but another option is to have a steady state solution where energy is generated leading to potentially large temperature gradients.

Re: 'Mathematically perfect' star system being investigated for potential alien tech

#209
post #191

Earlier quoted context omitted.

No. The temperature of the atmosphere has nothing to do with whether or not aliens are harvesting the energy. At equilibrium, all of the incoming energy has to get radiated back out into space eventually whether there are aliens harvesting that energy or not. The problem with an atmosphere hotter than lava is that very few materials are solid at those temperatures, and it's hard to imagine how a civilization could bu…

This is a great video that touches on your point, the Earth must radiate the heat it receives to stay in equilibrium, even if it uses it to do work in the process. https://www.youtube.com/watch?v=DxL2HoqLbyA

If we extract the maximum possible entropy of the incoming radiation wouldn't that mean we radiated at high-intensity but low-temperature?
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