egg changed the topic of #principia to: Logs: https://esper.irclog.whitequark.org/principia | <scott_manley> anyone that doubts the wisdom of retrograde bop needs to get the hell out | https://xkcd.com/323/ | <egg> calculating the influence of lamont on Pluto is a bit silly…
<queqiao-> ⟨alforath⟩ ugh ... it stops my spin stabilisation :/
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<_whitenotifier-ee4> [Principia] c6ForH66 closed issue #3811: Changing Integrator Causes Phobos to Escape from the Solar System - https://github.com/mockingbirdnest/Principia/issues/3811
<_whitenotifier-ee4> [Principia] c6ForH66 commented on issue #3811: Changing Integrator Causes Phobos to Escape from the Solar System - https://github.com/mockingbirdnest/Principia/issues/3811#issuecomment-1837027827
<_whitenotifier-ee4> [Principia] c6ForH66 commented on issue #3745: Feature request: descriptions of items in the orbit analyser - https://github.com/mockingbirdnest/Principia/issues/3745#issuecomment-1837028332
<_whitenotifier-ee4> [Principia] c6ForH66 commented on issue #3811: Changing Integrator Causes Phobos to Escape from the Solar System - https://github.com/mockingbirdnest/Principia/issues/3811#issuecomment-1837037496
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<_whitenotifier-ee4> [Principia] pleroy opened pull request #3812: A function to compute a collision between a vessel and a celestial - https://github.com/mockingbirdnest/Principia/pull/3812
<queqiao-> ⟨egg⟩ _stares at the reading comprehension skills of forumgoers_
<queqiao-> ⟨makoivis⟩ Oh, the optimization feature actually nailed a ballistic capture!
<queqiao-> ⟨makoivis⟩ Used optimization for the apogee correction burn
<queqiao-> ⟨egg⟩ Do you have a picture of the trajectory?
<queqiao-> ⟨makoivis⟩ I will once I get to my computer again
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<queqiao-> ⟨sorgan71⟩ i've heard people say that principia uses the terrain of planets in its calculations, is that true?
<queqiao-> ⟨egg⟩ Not sure where you heard that. Someone may be confused. The answer is “not yet”. But it soon will to report collisions. It has used geopotential models for years for gravity.
<queqiao-> ⟨egg⟩ * People
<queqiao-> ⟨sorgan71⟩ Wait, I dont understand, geopotential models are based on the terrain right?
<queqiao-> ⟨egg⟩ No.
<queqiao-> ⟨robbibi_⟩ they're predefined I think?
<queqiao-> ⟨robbibi_⟩ +for each planet
<queqiao-> ⟨robbibi_⟩ * body
<queqiao-> ⟨lpg4999⟩ you can't fool us, that's deimos with a weird texture
<queqiao-> ⟨sichelgaita⟩ It's a common mistake to think that the geopotential and the terrain have anything to do with one another. It's probably due to the fact that the Earth is an oblate spheroid, and the first order coefficient of the geopotential, J₂, reflects this. However, higher order coefficients are mostly influenced by the mantle, which is much denser than the crust. Counter-intuitively, mountains have buoyant roots that support them, so...
<queqiao-> ... the gravity field there is comparatively weaker.