raptop changed the topic of #kspacademia to: https://gist.github.com/pdn4kd/164b9b85435d87afbec0c3a7e69d3e6d | Dogs are cats. Spiders are cat interferometers. | Космизм сегодня! | Document well, for tomorrow you may get mauled by a ネコバス. | <UmbralRaptor> egg|nomz|egg: generally if your eyes are dewing over, that's not the weather. | <ferram4> I shall beat my problems to death with an engineer. | We can haz pdf
<_whitenotifier> [Principia] kc9jud commented on issue #1936: [Request] Multiple nodes editing - https://git.io/fh5zV
UmbralRaptop is now known as ObservatoryRaptor
* ObservatoryRaptor feels anxious about operating ~40 GMU student-years worth of telescope
<B787_300> what is that unit of measurement in non univeristy specific terms?
<ObservatoryRaptor> $800k
<B787_300> nice
<B787_300> which scope are you running?
<ObservatoryRaptor> The 0.8 m on the roof of one of the buildings.
<ObservatoryRaptor> … I think the tracking software is hitting a singularity or bug or something.
<ObservatoryRaptor> Oh, good. Aiming works.
<egg> yay
<egg> ObservatoryRaptor: is it a cat
<ObservatoryRaptor> RCT
<egg> bofh: whitequark ObservatoryRaptor: https://twitter.com/presentcorrect/status/1096423185388654593
<kmath> <presentcorrect> A new book documenting the cat ladders of Switzerland. ⏎ https://t.co/JjvStRT7n3 https://t.co/LY8L0ac8V6
<ObservatoryRaptor> cat and cat†?
<egg> "Synopsis - The example of the city of Bern is used to research Swiss cat ladders"
<egg> bofh: potential principia contributor?! https://www.researchgate.net/profile/Patrick_Fasano
<egg> (just commented on an issue asking how to help :-p)
<_whitenotifier> [Principia] eggrobin commented on issue #1936: [Request] Multiple nodes editing - https://git.io/fh5g4
e_14159 has quit [Ping timeout: 190 seconds]
e_14159 has joined #kspacademia
ObservatoryRaptor is now known as CursedRaptor
* egg meows at CursedRaptor
<CursedRaptor> The software, uh, really died.
<CursedRaptor> So we got 0 observations of the target star
<egg> ow
<CursedRaptor> Also, the telescope is probably inoperable for a while.
<CursedRaptor> This meant fun things like the observatory director walking me through some troubleshooting steps, and then how to manually close the dome.
<_whitenotifier> [Principia] eggrobin commented on issue #2074: An API to get geopotential coefficients for analytic perturbation theories - https://git.io/fh5gx
<egg> CursedRaptor: were hadrosaurs involved
<CursedRaptor> The dome was loud enough that there might have been.
<egg> <bofh> (i.e. I got distracted but I found the references I was looking for, so maybe another hour TT?) << haha
<_whitenotifier> [Principia] eggrobin opened pull request #2079: Geopotential API - https://git.io/fh52o
<_whitenotifier> [Principia] eggrobin edited pull request #2079: Geopotential API - https://git.io/fh52o
<egg|zzz|egg> EDC?
<egg|zzz|egg> !acr -add:EDC EUROLAS Data Center
<galois> Definition added!
<egg|zzz|egg> bofh: do you know whether there are SP3 files for GNSS satellites with V records and not just P records?
<egg|zzz|egg> I can find mentions of SP3 velocities in "GPS Satellite Velocity and Acceleration Determination using the Broadcast Ephemeris" but I can't find any SP3 with velocities for those satellites?!!
<egg|zzz|egg> bofh: MEOW
egg|zzz|egg has quit [Ping timeout: 183 seconds]
<kmath> <WalrockHomebrew> Though the Opportunity rover has gone on to robot heaven, it can live on in your #dnd game. ⏎ ⏎ Here's a fairly-accura… https://t.co/5Y8qWrwyrG
<bofh> 01:20:46 <@egg> bofh: potential principia contributor?! https://www.researchgate.net/profile/Patrick_Fasano
<bofh> Huh, interesting. Let's hope so? :P
<bofh> What the hell, there *should* be SP3 files for at least GPS
<bofh> one sec, I'm curious, I *swear* I actually saw some once.
<bofh> like you can't really calibrate DOP for GPS receivers without accurate velocities, so those *better* be available
<bofh> ftp://ftp.nga.mil/pub2/gps/navdata/2019/ worst-case scenario assemble them from RINEX? but that sounds absolutely vile
<bofh> http://www-app2.gfz-potsdam.de/pb1/igs/index_IGSP.html claims to have SP3s but the ftp is down?!
<bofh> AHH
<bofh> FOUND THEM
<bofh> ftp://ftp.nga.mil/pub2/gps/apcpe/2019apc/
<bofh> http://earth-info.nga.mil/GandG/sathtml/PEexe.html and hilariously, self-extracting ZIP files for some of the older ones (redundant with ftp, but hilarious)
ferram4_ has joined #kspacademia
ferram4 has quit [Ping timeout: 198 seconds]
egg|zzz|egg has joined #kspacademia
<egg> gah, WGS84
<egg> bofh: thanks
<egg> bofh: I'm surprised there aren't any V records in the IGS data
<egg> bofh: this has plenty of SP3-c files, but they're all P only ftp://cddis.nasa.gov/gnss/products/
<egg> bofh: what's the difference between the pe and apc solutions? ftp://ftp.nga.mil/pub2/gps/pedata/2019pe/nga20342.eph vs. ftp://ftp.nga.mil/pub2/gps/apcpe/2019apc/nga20342.apc
<CursedRaptor> sometimes this bot nails it https://botsin.space/@problembot/101607329043219227
<egg> hm, I see a GNSS data processing exercise book mentioning APC http://gage.upc.edu/sites/default/files/TEACHING_MATERIAL/GNSS_Book/ESA_GNSS-Book_TM-23_Vol_II.pdf
<egg> !acr -add:APC Antenna Phase Centre
<galois> Definition added!
<egg|zzz|egg> SP3?
<galois> SP3: Standard Product 3
<egg|zzz|egg> SINEX?
<galois> SINEX: Solution (software/technique) INdependent EXchange format
<egg|zzz|egg> !acr -add:ANTEX ANTenna EXchange format
<galois> Definition added!
<egg|zzz|egg> !acr -add:CODE Centre for Orbit Determination in Europe
<galois> Definition added!
<egg|zzz|egg> bofh: meow
<egg|zzz|egg> ;8ball is bofh awake
<kmath> egg|zzz|egg: Yeah
<egg|zzz|egg> bofh: hm, http://earth-info.nga.mil/GandG/sathtml/ephemeris.html pedata has centre of mass precise ephemerides, whereas the other is APCs
<egg|zzz|egg> "Note: Unlike the IGS igs15681.sp3 file, the satellite coordinates in the apc15681 file are relative to the satellite’s APC. Therefore, the APC correction must be applied to the IGS file to relate both coordinates to their respective APC."
<egg|zzz|egg> ah, that's what the SATCOM and SATAPC in the comment lines mean
<egg|zzz|egg> bofh: e.g. here in the com* files, there are positions for all of GPS, ГЛОНАСС, and Galileo, but no velocities ftp://igs.ensg.ign.fr/pub/igs/products/mgex/1700/
<egg|zzz|egg> !acr -add:KASI Korea Astronomy and Space science Institute
<galois> Definition added!
egg|zzz|egg has quit [Ping timeout: 202 seconds]
egg|zzz|egg has joined #kspacademia
<egg|zzz|egg> !acr -add:PRN Pseudo-Random Noise
<galois> Definition added!
<egg|zzz|egg> bofh: do you think it is meaningful to interpolate the velocities by a high-order difference formula from those P-only SP3 files?
<egg|zzz|egg> (they have data every 15 min)
<egg|zzz|egg> !acr -add:NAVSTAR NAVigation System using Timing And Ranging
<galois> Definition added!
<egg|zzz|egg> !acr -add:MGEX Multi-GNSS EXperiment
<galois> ...
<egg|zzz|egg> !acr -add:QZSS Quasi-Zenith Satellite System
<galois> ...
<egg|zzz|egg> bofh: actually ever 5 min from CODE since week 1962 http://mgex.igs.org/IGS_MGEX_Products.php
<egg|zzz|egg> + 81 G01G02G03G04G05G06G07G08G09G10G11G12G13G14G15G16G17 + G18G19G20G21G22G23G24G25G26G27G28G29G30G31G32R01R02 + R03R04R07R08R09R10R11R13R14R15R16R17R18R19R20R21R22 + R23R24E01E02E03E04E05E07E08E09E11E12E14E18E19E21E24 + E26E30C06C07C08C09C10C11C12C13C14J01J02 0 0 0 0
<egg|zzz|egg> the SP3-c format is doing a lot of work
<_whitenotifier> [Principia] pleroy commented on issue #1936: [Request] Multiple nodes editing - https://git.io/fh56g
<bofh> egg|zzz|egg: meow
<egg|zzz|egg> bofh: meow
<bofh> is there much of a difference between an APC and a Centre-of-Mass one? Yes I know what the difference is, and I think you'd be interested in the latter and me in the former, but from what I can tell the ccorrection is of a very smol magnitude?
<bofh> 14:21:39 < egg|zzz|egg> bofh: do you think it is meaningful to interpolate the velocities by a high-order difference formula from those P-only SP3 files?
<bofh> should be meaningful, I mean they're... hourly? or apparently even every 5 mins?!?
<egg|zzz|egg> is there much of a difference between an APC and a Centre-of-Mass one? well you can compare them yourself ftp://ftp.nga.mil/pub2/gps/pedata/2019pe/nga20342.eph vs. ftp://ftp.nga.mil/pub2/gps/apcpe/2019apc/nga20342.apc
<_whitenotifier> [Principia] pleroy commented on issue #2063: Principia DLL failed to load - https://git.io/fh56M
<bofh> yeah, the corrections seem very smol :P
egg|zzz|egg has quit [Ping timeout: 180 seconds]
<kmath> <bofh453> Huh, I didn't know 𒀭𒉀 still lived among us & apparently was responsible for YAML's numeric parsing behaviour… https://t.co/7o3gtBWpNp
<_whitenotifier> [Principia] pleroy reviewed pull request #2079 commit - https://git.io/fh5iE
<_whitenotifier> [Principia] pleroy reviewed pull request #2079 commit - https://git.io/fh5iu
<_whitenotifier> [Principia] pleroy labeled pull request #2079: Geopotential API - https://git.io/fh52o
egg|zzz|egg has joined #kspacademia
<egg> <bofh> should be meaningful, I mean they're... hourly? or apparently even every 5 mins?!? << used to be every 15 min, now every 5 min from CODE for MGEX (but every 15 min for a lot of other stuff still)
egg|zzz|egg has quit [Ping timeout: 202 seconds]
<bofh> Every 5 mins seems weirdly frequent tbh.
<bofh> egg: https://twitter.com/sigfig/status/1093291620328448000 I feel like the top one is you and the bottom one me
<kmath> <sigfig> me after skipping a meal: feelin great, energetic, starving has mysteriously cured all my ailments ⏎ ⏎ alice after ski… https://t.co/SeKHRaGB1Y
<egg> pretty much
<_whitenotifier> [Principia] eggrobin synchronize pull request #2079: Geopotential API - https://git.io/fh52o
<egg> bofh: hm, I feel like the best way to test https://github.com/mockingbirdnest/Principia/issues/2072 is going to be to build a transporter-erector launcher and drive it to the beach
<_whitenotifier> [Principia] Pending. Build queued… - 
<_whitenotifier> [Principia] Pending. Building… - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3450/
<egg> NGA?
<egg> !acr -add:NGA National Geospatial-intelligence Agency
<galois> Definition added!
<egg> STARLETTE?
<galois> STARLETTE: Satellite de Taille Adaptée avec Réflecteurs Laser pour les ÉTudes de la TErre
egg|zzz|egg has joined #kspacademia
<bofh> egg: LOL
<egg> bofh: LOL at what specifically
<bofh> building a TEL and driving it to the beach to test parachute effectiveness at low heights :P
egg|zzz|egg has quit [Ping timeout: 189 seconds]
<_whitenotifier> [Principia] Failure. Build finished. - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3450/
<egg> bofh: well it's really all intrinsic forces being ignored
<egg> bofh: so the missile should flop to the ground
<_whitenotifier> [Principia] eggrobin synchronize pull request #2079: Geopotential API - https://git.io/fh52o
<_whitenotifier> [Principia] Pending. Build queued… - 
<_whitenotifier> [Principia] Pending. Building… - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3451/
<egg> hm I can't seem to control the steering of my TEL
<bofh> I'm sorry, I still can't get over the concept of a TEL in Principia
<egg> hey now it steers \o/
<egg> hm also it has fewer wheels on the right side
<_whitenotifier> [Principia] Success. Build finished. - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3451/
<egg> ... and having run into a bump into the runway, it has more on the right side.
<_whitenotifier> [Principia] pleroy reviewed pull request #2079 commit - https://git.io/fh5XQ
<_whitenotifier> [Principia] pleroy opened pull request #2080: Fix a link error found on Linux - https://git.io/fh51y
<_whitenotifier> [Principia] Pending. Build queued… - 
<_whitenotifier> [Principia] Pending. Building… - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3452/
<bofh> yeah I assume it having unequal numbers of wheels on each size would lead to steering difficulties :P
<_whitenotifier> [Principia] Success. Build finished. - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3452/
<_whitenotifier> [Principia] eggrobin synchronize pull request #2079: Geopotential API - https://git.io/fh52o
<egg> bofh: unfortunately the cunning TEL plan did not work
<_whitenotifier> [Principia] Pending. Build queued… - 
<_whitenotifier> [Principia] Pending. Building… - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3453/
<bofh> egg: oh?
<egg> the things launched fine even if the TEL was floating
<egg> I think that's because for a few frames Principia doesn't control the missiles
<egg> and then they're above 8 m
<egg> bofh: so I just ended up parachuting a capsule to test the parachute issue, which is boring
<egg> I did build a TEL though
egg|zzz|egg has joined #kspacademia
egg|zzz|egg has quit [Ping timeout: 180 seconds]
egg|zzz|egg has joined #kspacademia
<_whitenotifier> [Principia] Success. Build finished. - http://casanova.westeurope.cloudapp.azure.com:8080/job/Principia/3453/
egg|zzz|egg has quit [Ping timeout: 189 seconds]
<bofh> egg: I mean parachute-delivered missiles are a thing, I think.
<bofh> still cackling at building a TEL
<bofh> next up: over-the-horizon radar in Principia? :P
<bofh> I have an HF propagation model here somewhere that I wrote ages ago (it's in Fortran, mind you)
<bofh> It mostly implements f0F2 so it's not very useful during the day, but OTOH neither are the bands I care about so.
egg|zzz|egg has joined #kspacademia
<_whitenotifier> [Principia] eggrobin labeled pull request #2080: Fix a link error found on Linux - https://git.io/fh51y
<_whitenotifier> [Principia] eggrobin closed pull request #2080: Fix a link error found on Linux - https://git.io/fh51y
<_whitenotifier> [Principia] eggrobin pushed 4 commits to master [+0/-0/±11] https://git.io/fh5yw
<_whitenotifier> [Principia] pleroy 2a5e0ee - Fix a link error found on Linux.
<_whitenotifier> [Principia] pleroy 7f75e37 - Remove useless dependencies.
<_whitenotifier> [Principia] pleroy c3e2680 - Usages.
<_whitenotifier> [Principia] eggrobin 60d9122 - Merge pull request #2080 from pleroy/Linux Fix a link error found on Linux
<_whitenotifier> [Principia] eggrobin closed issue #2074: An API to get geopotential coefficients for analytic perturbation theories - https://git.io/fhQfk
<_whitenotifier> [Principia] eggrobin closed pull request #2079: Geopotential API - https://git.io/fh52o
<_whitenotifier> [Principia] eggrobin pushed 5 commits to master [+0/-0/±10] https://git.io/fh5yr
<_whitenotifier> [Principia] eggrobin 633e018 - Geopotential API
<_whitenotifier> [Principia] eggrobin 80daecb - after pleroy's review
<_whitenotifier> [Principia] eggrobin 381a8b1 - rename in the test too
<_whitenotifier> [Principia] ... and 2 more commits.
CursedRaptor has quit [Remote host closed the connection]
<egg|zzz|egg> bofh: should I use a difference formula on the ECEF positions to get ECEF velocities, or convert and differentiate the ECI positions to get ECI velocities
<egg|zzz|egg> bofh: (not an urgent question since now I need to finally get around to writing an SP3 parser)
<egg|zzz|egg> whitequark: do you like specs ftp://igs.org/pub/data/format/sp3c.txt
<egg|zzz|egg> oh interesting https://cddis.nasa.gov/sp3c_satlist.html
UmbralRaptop has joined #kspacademia
* egg meows at whitequark and котеньке
<bofh> whitequark: so uh working with rotational reference frames sounds gross, I'd use the ECI positions to get ECI velocities tbh.
<egg> bofh: why should it make the differencing better or worse?
<egg> !wpn whitequark
* galois gives whitequark a hexaflexagon with a morphism attachment
<egg> !wpn bofh
* galois gives bofh a morphism
egg|zzz|egg has quit [Ping timeout: 189 seconds]
<kmath> <BeckePhysics> @Patchemup1 @BadAstronomer Unfortunately not. @ESO https://t.co/UBwhGuR7Jd
<egg> bofh: I ended up not needing it, but I made a TEL https://imgur.com/a/9JucFlp
egg|zzz|egg has joined #kspacademia
<egg|zzz|egg> !acr -add:NAVIC NAVigation with Indian Constellation
<galois> Definition added!
<egg|zzz|egg> !acr -add:IRNSS Indian Regional Navigation Satellite System
<galois> Definition added!
<egg|zzz|egg> bofh: hm, are there SP3 files for NAVIC/IRNSS
<egg|zzz|egg> bofh: they have SP3 designations, but it seems MGEX products don't have them? https://cddis.nasa.gov/sp3c_satlist.html
<egg|zzz|egg> they're mentioned on this MGEX page though http://mgex.igs.org/analysis/index.php
* UmbralRaptop 🔪 SR
<bofh> Huh, TIL IRNSS is a thing.
<egg|zzz|egg> bofh: they even have laser ranging! ftp://cddis.gsfc.nasa.gov/pub/slr/data/npt_crd/
<egg|zzz|egg> bofh: no i am not parsing normal point data to fit ephemerides to that, I have not reached that level of insanity
<egg|zzz|egg> bofh: I'll stick to SP3
<bofh> I was about to say, that's, like, at least two strata of hell lower than parsing SP3, lol.
<egg|zzz|egg> bofh: I mean the NPT format is still semidecent: ftp://cddis.gsfc.nasa.gov/pub/slr/data/npt_crd/starlette/2019/starlette_20190101.npt