Hello, I have found some data errors and missing designations and classifications in the Solar System objects data. I did already post some of that on the thread "General questions about SpaceEngine". I have been busy for some time so I was unable to post this before. I did also discuss this on the thread "COMMUNITY ADDON - Double/Multiple Asteroids fixes for SE" primarily concerning bug in the addon on barycenters.

Mosfet did already make a fix concerning Hygiea, but I think the other problems I have found have not yet been fixed. I did also find some new problems conserning comets. It seems that the diameter gained from absolute magnitude calculations seem to be off for some comets. For example comet C/1995 O1 (Hale-Bopp) is given nucleus magnitude in JPL small body database as 6.1 and albedo as 0.04. Calculation gives comets diameter as 400km but studies on this comet have revealed that its size is probably about 60 km.

Some other comets on Space Engine, not C/1995 O1 itself have been given this kind of mega-sized diameter values which are probably wrong considering C/1995 O1 (Hale-Bopp). These most obviously wrong diameters given to comets in SE are C/2010 U3 (included as 470 km!!) and 110P/Hartley (included in SE as 439 km!) when it really is estimated to be only 4,3 km in diameter. Comet C/2006 S3 (LONEOS) is in SE as diameter 295 km, I am not sure but that may be wrong, seems quite large for a comet considering the error on comets 110P and C/2010 U3. Other curious comet is C/2009 P1 (Garradd) that is listed in SE as 115 km that seems also a bit large.

Following is a list of objects included in SE with errors that I have discovered so far:

Following comets have inaccurate properties:

Comet C/2010 U3 - diameter wrong: 470 km / correct: ? km

https://ssd.jpl.nasa.gov/sbdb.cgi#topComet C/1995 O1 (Hale-Bopp) - Included in SE as 66 km, that is the value given by studies but magnitude gives 400 km

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Hale-Boppww.physics.sfasu.edu/astro/asteroids/sizemagnitude.html

Comet 110P/Hartley - diameter wrong 439 km / correct: 4.3 km (13.3 mag)

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=110PComet 47P/Ashbrook-Jackson - diameter wrong: 386.57 km/ correct: 5.6 km

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=47PComet 9P/Tempel - diameter wrong: 67 km / correct: 6.0 km

Rotation wrong: 2.559 d / correct: 40.7 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=9pComet 10P/Tempel - diameter wrong: 83.85 km / correct: 10.6 km

rotation wrong: 42 h / correct: 8.93 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=10pComet 31P/Schwassmann-Wachmann - diameter wrong: 74.38 km / correct: 6.2 km

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=31pComet 117P/Helin-Roman-Alu - diameter wrong: 205.59 km / correct: 9 km

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=117PComet 74P/Smirnova-Chernykh - diameter wrong: 72 km / correct: 4.46 km

rotation wrong: d / correct: h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=74PComet C/2011 KP36 (Spacewatch) - diameter wrong: 93 km / correct: 55.100 km

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C/2006 S3 (LONEOS) - diameter probably wrong: 295 km / correct: ? km

https://ssd.jpl.nasa.gov/sbdb.cgi#topComet C/2009 P1 (Garradd) - Is the diameter wrong?: 115 km

https://ssd.jpl.nasa.gov/sbdb.cgi#topFollowing asteroids have inaccurate properties:

Hygiea - diameter wrong: 862 km /correct: 407 km

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=HygieaInteramnia - diameter wrong: 181.76 km /correct: 306.313 km

rotation wrong: 7.922 d /correct: 8.727 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=InteramniaDavida - diameter wrong: 132.49 km / correct: 270.327 km

rotation wrong: 9.258 d /correct: 5.1297 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Davida Cybele - diameter wrong: 106.82 km / correct: 237.26km

rotation wrong: 10.335 d /correct: 6.0814 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=CybeleEuropa (asteroid) - diameter wrong: 142.67 km / correct: 303.918 km

rotation wrong: 8.952 d /correct: 5.6304 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=EuropaHebe - diameter wrong?: 167.29 km / correct: 185.18 km

rotation wrong: 8.24 d /correct: 7.2745 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=HebeAstraea - diameter wrong?: 109.82 km / correct: 106.699 km

rotation wrong: 10.175 d /correct: 16.806 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Astraea Iris - diameter wrong?: 204 km / correct: 199.83 km

rotation wrong: 7.457 d /correct: 7.139 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=IrisFlora - diameter wrong?: 136.87 km / correct: 147.491 km

rotation wrong: 9.104 d /correct: 12.865 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=FloraMetis (asteroid) - diameter wrong?: 137.19 km / correct: 190 km

rotation wrong: 9.083 d /correct: 5.079 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=MetisParthenope - diameter wrong?: 124.55 km / correct: 142.887 km

rotation wrong: 9.560 d /correct: 13.7204 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=ParthenopeVictoria - diameter wrong?: 80.2 km / correct: 115.087 km

rotation wrong: 11.893 d /correct: 8.6599 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=VictoriaEgeria - diameter wrong?: 104.67 km / correct: 222.792 km

rotation wrong: 10.429 d /correct: 7.045 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=EgeriaIrene - diameter wrong?: 144.88 km / correct: 152 km

rotation wrong: 8.864 d /correct: 15.028 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=IreneEunomia - diameter wrong?: 217.17 km / correct: 231.689 km

rotation wrong: 7.255 d /correct: 6.083 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=EunomiaPsyche - diameter wrong?: 166 km / correct?: old estimate 253 – new 196 km

rotation wrong: 8.295 d /correct: 4.196 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Psychehttp://www.occultations.org.nz/planet/2 ... psyche.htmPhilippina - diameter wrong?: 45.82 km / correct: 50.491 km

rotation wrong: 15.828 d /correct: 5.899 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=PhilippinaNemesis - diameter wrong: 69.73 km / correct: 162.515 km

rotation wrong: 12.79 d /correct: 77.81 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=NemesisLutetia - diameter wrong?: 84.73 km / correct: 95.76 km

rotation wrong: 11.571 d /correct: 8.1655 h

(Realistic shape and texture are missing.)

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=LutetiaFollowing TNO:s have inaccurate properties:

Chaos - diameter wrong: 238.43 km /correct: 600+140−130 km

https://arxiv.org/pdf/1204.0697v1.pdfHuya – rotation wrong? 13 h / correct? 5.28 h

http://www.johnstonsarchive.net/astro/a ... 38628.html Sedna – diameter wrong: 1700 km / correct: 995 ± 80 km

rotation wrong: 2.6 d / correct: 10.273 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Sednahttp://adsabs.harvard.edu/abs/2012A&A...541L...6PQuaoar – diameter wrong? 1250 km / correct: 1073.6 ± 37.9 km

rotation wrong? 17 h/ correct: 8.839 h?

http://www.aanda.org/articles/aa/pdf/20 ... 329-13.pdfhttp://www.johnstonsarchive.net/astro/a ... 50000.htmlhttps://ssd.jpl.nasa.gov/sbdb.cgi?sstr=QuaoarVaruna – rotation wrong: 3.5 d / correct: 6.3436 h

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Varuna2010 EK139 – diameter wrong? 414.77 km /correct:? 470+35-10 km

rotation wrong: 5.266 d / correct: 7.07 h

minor planet designation (alternate name) is missing, that is: (471143) 2010 EK139

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=471143http://adsabs.harvard.edu/abs/2012A&A...541L...6PFollowing dual classification objects (minor planet and comet) are missing one or another designation. One is shown with only its minor planet designation, others are displayed with comet designations only (inconsistent data in game). Some of them also have incorrect properties:

Chiron / (2060) Chiron - comet designation is missing, that is: 95P Chiron

Also Chiron's coma is missing

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Chironhttp://www.minorplanetcenter.net/iau/li ... tatus.htmlhttps://www.researchgate.net/publicatio ... d_its_comaEcheclus / 174P Echeclus - diameter wrong: 8.57 km / correct: 59 km

rotation wrong: 16 h /correct: 26.802 h

minor planet designation (alternate name) is missing, that is: (60558) Echeclus

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Echeclushttp://www.minorplanetcenter.net/iau/li ... tatus.htmlElst-Pizarro / 133P Elst-Pizarro - diameter wrong: 0.774 km / correct: 3.200 km

pyörähdysaika väärä: 20 h /correct: 3.471 h

minor planet designation (alternate name) is missing, that is: (7968) Elst-Pizarro

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=133Phttp://www.minorplanetcenter.net/iau/li ... tatus.htmlLINEAR / 176P LINEAR - diameter wrong: 0.763 km / correct: 3.5 km

minor planet designation (alternate name) is missing, that is: (118401) LINEAR

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=176Phttp://www.minorplanetcenter.net/iau/li ... tatus.htmlWilson-Harrington / (4015) Wilson-Harrington / 107P Wilson-Harrington – is missing entirely from the game

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=107Phttp://www.minorplanetcenter.net/iau/li ... tatus.htmlDwarf planets and TNO:s have their minor planet designations (alternate names) shown in the game. Following dwarf planets are missing their minor planet designations (inconsistent data in game):

Pluto - Minor planet designation (alternate name) is missing, that is: (134340) Pluto

https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=Plutohttp://www.minorplanetcenter.net/iau/lists/TNOs.htmlhttp://www.minorplanetcenter.net/dwarf_planetshttp://www.minorplanetcenter.net/db_sea ... _id=134340http://www.minorplanetcenter.net/iau/mp ... 06R19.htmlPluto's moon Nix seems to be missing realistic shape and texture. Following moons/dwarf moons are missing their satellite designations (inconsistent data in game):

Galilean moons of Jupiter

Dysnomia of Eris

Moons of Pluto

Moons of Mars

https://planetarynames.wr.usgs.gov/Page/PlanetsFollowing interesting objects are missing from SE:

Moon of TNO 1998WW31 is missing, TNO:s Arawn, 1992 QB1, 1993 RO and 1993 SB are missing. 1992 QB1, 1993 RO, and 1993 SB are all early discovered TNO:s and so it would be nice if they would be included. Arawn was studied realively close by by New Horizons spacecraft so there is relatively accurate info on its properties.

Asteroids Steins, Mathilde, Annefrank and Braille are missing. These asteroids have been studied close by by spacecrafts, so there is accurate data on them.

Comets 81P/Wild and 103P/Hartley that were studied close by spacecrafts are missing.

Also, considering their diameters, why are Neptune's Nereid and Proteus classed as moons but Eris' Dysnomia as a dwarf moon?