raptop changed the topic of #principia to: READ THE FAQ: http://goo.gl/gMZF9H; The current version is Gateaux. We currently target 1.8.1, 1.9.1, and 1.10.1. <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… | <egg> also 4e16 m * 2^-52 is uncomfortably large
<discord->
Damien. — It was painful to do all the trial and error to get the ascent right
<discord->
Damien. — This was before the rotation bug was fixed so I couldn't capture using the retromotor
<discord->
egg. — do you notice a performance degradation when using the orbit analyser? trying to figure out if something I am eggsperimenting with is a problem or if it’s just my laptop being a potato
<discord->
egg. — OK it’s probably better if I don’t have three YouTube tabs
<discord->
egg. — hm, polar instead of quasi-polar for 80°–100° is an abuse of language that is quite common, but calling 10° equatorial is quite a stretch…
<discord->
egg. — well, in terms of staring at noodles in ECI it seems like a stretch; but then when you think about the sub-satellite point I guess it is still a fairly narrow band
<discord->
DRVeyl. — 10 sounds like a lot, 5 sounds a bit more like rounding error / colloquial usage. But maybe just splitting hairs here.
<discord->
egg. — @DRVeyl I’m getting that 10 just from the one definition in a book, it’d be nice to survey a bunch of applications to see what makes sense. It definitely needs to be beyond 1°.5 since there is a 北斗 GEO sat in those waters ; what is the half-aperture of the field of view of your standard-issue household parabola for instance ? since that’s one constraint on some GEO sats
<discord->
DRVeyl. — Fairly wide, typically, but that's partially because untrained users need to be able to point them. (Spacecraft makes up for some inefficiency.)
<discord->
DRVeyl. —
<discord->
DRVeyl. — Plugging in a few numbers for reference. 0.75m dish at 12GHz (approximate for DishTV) is 1.1 degree half power beamwidth
<discord->
DRVeyl. — Fairly wide, typically, but that's partially because untrained users need to be able to point them. (Spacecraft makes up for some inefficiency.)
<discord->
DRVeyl. —
<discord->
DRVeyl. — Plugging in a few numbers for reference. 0.75m dish at 12GHz (approximate for DishTV) is 2.2 degree half power beamwidth (edited)
<discord->
DRVeyl. — (So you can mis-point by 1.1 degrees for a loss of 3dB = half power)
<discord->
egg. — right, far cry from 10° though.
<discord->
egg. — the 10°ish probably makes sense when looking at an earth observation satellite : a satellite on an equatorial orbit looks at the regions with equatorial climates, see, e.g. http://css.unoosa.org/pdf/pres/stsc2007/cospar-iaf-06.pdf (though they use near-equatorial for the 10° case)
<discord->
egg. — but calling 10° synchronous circular « stationary » is silly
<_whitenotifier-9244>
[Principia] pleroy closed pull request #2800: Change the apodization functions to be centred - https://git.io/JkbFw
<_whitenotifier-9244>
[Principia] pleroy pushed 7 commits to master [+0/-0/±16] https://git.io/JkxqS
<_whitenotifier-9244>
[Principia] pleroy 23a1430 - Change the apodization functions to be centred on their intervals.
<_whitenotifier-9244>
[Principia] pleroy 8b93ba5 - Change the test to construct origin-compatible series. Fix a bug in the construction of the base. Start with more points in Clenshaw-Curtis.
<_whitenotifier-9244>
[Principia] pleroy eac6d73 - Adjust the tolerances.
<_whitenotifier-9244>
[Principia] ... and 4 more commits.
<discord->
egg. — yeah but that’s 2° of FoV, not 2° of longitude, so we still have to compute what the width of the swath is on the Earth
<discord->
Butcher. — Oh true.
<discord->
egg. — 2° of aperture or half-aperture
<discord->
Butcher. — Not sure.
<discord->
Butcher. — It's 262km wide at earth surface.
<discord->
Butcher. — But that is either half swath or full.
<discord->
egg. — ah, that makes it easy :-p
<discord->
egg. — right, so that question remains.
<discord->
Butcher. — 262km wide is just me doing trig. 😉
<discord->
Butcher. — Hmm, eyeballing the scansat map, about 6° long coverage at the equator for a swath.
<discord->
Butcher. — So half aperture.
<discord->
egg. — OK, so you get about a third of overlap at the equator.
<discord->
Butcher. — I do appear to have complete coverage at the equator, though oddly not at the tropics.
<discord->
egg. — and the subcycle tells you that if you have something in the correct (I forget how to figure out if it’s east or west) third of the image, you’ll see it again in 7 days, rather than the full 18 days of the cycle
<discord->
Butcher. — As this is for altimetry, it doesn't need frequent overflys, it's not the sort of thing that changes week to week.
<discord->
egg. — so if you can see something you’ll see it within 12 days (cycle), and with the extrawide swath that covers two grid intervals you’ll see it within 5 days
<discord->
egg. — that would be with only one satellite though, but you have 1A and 1B
<discord->
egg. — doing a pass over the two subreddits to see if there are people confused about Principia; interestingly there seems to be more people using it and less confusion than last time I did so
<discord->
Butcher. — I have bumped it to 0.005
<discord->
Butcher. — Also I'm thinking a sun synchronous orbit for power reasons.
<discord->
Butcher. — Come to think of it, I wonder how bad my solar panels will be after 20 years.
<discord->
lpg. — planning on staying below analytic warp speed for 20 years?
<discord->
egg. — is that earth observation or sky?
<discord->
Butcher. — Oh I forgot the stupid analytic mode.
<discord->
lpg. — (I put 2 up, to cut that down to 10)
<discord->
egg. — clearly @Sir Mortimer must be poked :-p
<discord->
Butcher. — I'll just add solar. 6 kW of panels is doable.
<discord->
Butcher. — @egg Sky.
<discord->
Butcher. — It's modelled on HST.
<discord->
lpg. — data throughput is another fun challenge for that one
<discord->
Butcher. — X band omni should be adequate I think.
<discord->
Butcher. — 1.13 mbps when connected.
<discord->
Butcher. — If I have a lot of data buffering I might upgrade my GEO commsat to have xband.
<discord->
lpg. — "when connected" is the rub. x band is DSN only, I think
<discord->
egg. — right; then crepuscular is a good idea I think, that also means you can always look in the direction opposite the sun
<discord->
Butcher. — It is.
<discord->
egg. — alternatively if you do a survey you can do the IRAS/COBE/明かり/WISE thing and look up at all times, scanning the whole sky over a year, and you always look at right angles to the sun in the process
* umbralraptop
wants to say that you end up looking not so much directly opposite the sun as sideways for various craft design reasons
<discord->
Butcher. — Hmm, time to see what X band relays can do.
egg|laptop|egg has quit [Ping timeout: 194 seconds]
egg|laptop|egg has joined #principia
<discord->
DRVeyl. — X is currently only configured for DSN. Same with K (or Ka, I forget which I used). Of course, could always look into the Near Earth Network, which is what Earth observation sats are going to use.
<discord->
DRVeyl. — I started on some ESTRACK but never got around to it
<discord->
egg. — do we have estrack in RSS? I—
<discord->
egg. — :D
<discord->
Butcher. — I'm just going to launch a couple of X band dishes into GEO to relay. :-p
Jesin has quit [Quit: Leaving]
egg|laptop|egg has quit [Remote host closed the connection]
egg|laptop|egg has joined #principia
<discord->
egg. — I meant to add the St Jean du Maroni flanking station for Vega launches ages ago and never got to it
<discord->
egg. — then again I guess you don’t need a flanking station until someone decides to start modelling SRB exhaust interfering with radio (cc @DRVeyl :-p)
<discord->
DRVeyl. — Maybe after I start to model the vessel itself blocking. Insert all the reasons why that is not a great idea
<discord->
egg. — eh, when we get around to attitude-keeping in Principia that should become reasonable
<discord->
DRVeyl. — Orientation of maneuver not often suitable for orientation of especially fixed antenna. Not sure what a solution would be in KSP.
<discord->
egg. — ah, you mean for downlink-dependent control, not data downlink?
Jesin has joined #principia
<discord->
egg. — (isn’t the answer to that that downlink-dependent control is silly and that you play the onboard computer?)
<discord->
DRVeyl. — You play the onboard computer, but link is still considered required.
<discord->
egg. — yeah that quickly breaks down, you’d have to drop that requirement (or at least allow control for a good while after successful AOS)
<_whitenotifier-9244>
[Principia] pleroy synchronize pull request #2801: Use parity in basis subspaces - https://git.io/JkxFH
<discord->
egg. — (but even then, unless you want players to write their own « get out of safe mode, find known stars, point at the earth » code, that’s oddly restrictive)
<discord->
DRVeyl. — Yep. Could rewrite the set of control locks that get placed, maybe, but not convinced that is sufficiently interesting or worthwhile.
<discord->
DRVeyl. — (It's currently stock behavior.)
<discord->
egg. — yeah, and definitely speculative until attitude-keeping actually eggsists
<discord->
egg. — (living with just spin-stabilization is very restrictive, especially if that starts to affect comms and not just solar panels)
egg|laptop|egg has quit [Remote host closed the connection]
<discord->
Kirk. — Modeling vessel occlusion of antennas would mean people would start covering their probes in medium gain antennas like IRL
<discord->
lpg. — Not that I'm on board with this, but if that were to be a goal, RA would more or less _have_ to give up its 'antenna parts represent all the radio hardware' approach
<discord->
Butcher. — Just put a ton of communotrons on everything. I
<discord->
[experimentalshells?]. — if I remember correctly, more than one of these were antennas
<discord->
Standecco. — not sure what's your actual plan, and if it is any different than a long button full of words, but I wouldn't add it to an already existing button, but I'd rather insert a new string, akin to the current version string, next to the flight plan button
<discord->
Standecco. — not sure what's your actual plan, and if it is any different than a long button full of words, but I wouldn't add it to an already existing button. I'd rather insert a new string, akin to the current version string, next to the flight plan button (edited)
<discord->
Standecco. — not sure what's your actual plan, and if it is any different than a long button full of words, but I wouldn't add it to an already existing button. I'd rather insert a new string, akin to the current version string, next to the flight plan (edited)
<discord->
egg. — Well, my current plan is the button full of words, akin to the plotting frame button
<discord->
egg. — A new field would mean a bigger UI, and it's annoyingly big as it is
<discord->
Standecco. — right, the entire UI needs a redesign
<discord->
DRVeyl. — Yeah. Breaking the paradigm that the electronics are an element of each antenna part and turning it into more of a system of components would be a little irritating.
<discord->
DRVeyl. — Not horrible. But irritating.
<umbralraptop>
The horrible version involves implementing Maxwell's egguations
<discord->
DRVeyl. — Well, I have them on a T-shirt for easy reference. (The better version of it had them written upside down on the front)
<umbralraptop>
But did you have the version with 4 egguations, or the relativistic one with only 2?