(1) Canon of Solar Eclipses from BCE 13000 to CE 17000 has been reworked. I have enhanced scanning resolution, so times of Greatest Eclipse are now correct to ± 0.05s, referred to the Lunar Center of Mass. This value is independent from DeltaT, so follows the accuracy of DE440 or DE441 through the time. I have added further information such as the location of Greatest Eclipse (these values depend on DeltaT instead) , the duration of Totality or Annularity and the Path Width again referred to the G.E. The Eclipse Magnitude should not be confused with Semidiameters ratio, generating another value. Gamma and L2 values are directly deduced from computed Besselian Elements for the Eclipse.
(2) Distance Panel: added two new values, Arc of Vision (known also as Arcus Visionis) and Azimuth Difference, useful for determination of Heliacal Rising, Setting and so on.
(3) Distance Panel: added Arcturus to the list of available objects.
(4) Polar flattening of Jupiter and Saturn is shown now on the EQT and HOR views.
(5) Added to managed objects the eight main satellites of Saturn. The rings of Saturn still remain to be managed. I have already calculated the numbers but have to find a decent way to represent them.
(6) Added Rotation Axis to Mercury and Venus.
(7) Some variation on the main window:
- Modified the color of Saturn’s disk.
- Unified into a panel the Cursor Coordinates.
- Moved Terminal Buttons to the left and made some room for future buttons.
Hi
The Distance Panel is a very useful feature.
I was using for Sirius the IMCCE formulae (2003) :
https://promenade.imcce.fr/en/pages6/724.html
Buona fortuna con tutti questi miglioramenti.
Regards.
Buongiorno.
Molto interessante il pannello distanza orizzontale per quantificare anche i fenomeni eliaci (non ancora attivo sul mio pc). Quando le sarà possibile dovrebbe aggiungere alla lista delle stelle anche Arcturus, che come è noto rivestiva grande rilevanza nei fenomeni eliaci nell’antichità.
Grazie
Luigi
Sì, grazie. Se ho dimenticato di inserire qualche astro significativo fate bene a segnalarmelo così posso aggiungerlo alla lista. In effetti popolazioni dall’agricoltura molto differenziata come i Celti usavano gli eventi eliaci di molte stelle brillanti, spero di averle incluse più o meno tutte. Non ho intenzione di creare una lunghissima lista piena di astri poi nella pratica inutili, ma quelli in effetti utilizzati vorrei ci fossero tutti.
Grazie
Alberto
Hi
Just for the record, the new ephemeris INPOP21a published by IMCCE/Paris Observatory :
https://www.imcce.fr/content/medias/recherche/equipes/asd/inpop/inpop21a.pdf
Article in English.
However time period (years from J2000) -1000 to 1000
Regards
Thanks for the info.
Thanks Bercu, I have already implemented INPOP21a in CdC.
Hi Kamil
I have not implemented INPOP21a yet. Do you find a difference with JPL DE440 and DE441 ?
I guess the results must be very close.
However, it is always interesting to compare ephemeris calculated by two different sources.
Regards
Hi
Bercu
For comparison, here are some moon positions
in the indicated range of INPOP21a ephemeris from J2000.0.
Astrometric right ascension and declination of the target center with
respect to the observing site (coordinate origin) in the reference frame of
the planetary ephemeris (ICRF).
MOON
Date: 1000-Aug-15 0h TT R.A.: 20h48m06.708s DE441 Cartes du Ciel (CdC)
DEC : -23°09’40.76”
R.A.: 20h48m06.70797s DE441 JPL HORIZONS ΔT=1656.91s
DEC : -23°09’40.75733”
R.A.: 20h48m09.068s INPOP21a (CdC)
DEC : -23°09’31.02”
Date: 1600-Aug-15 0h TT R.A.: 14h08m20.337s DE441 (CdC)
DEC : -18°26’52.52”
R.A.: 14h08m20.337244s DE441 JPL HORIZONS ΔT=109.481s
DEC : -18°26’52.51760”
R.A.: 14h08m20.356s INPOP21a (CdC)
DEC : -18°26’32.61”
Date: 1700-Aug-15 0h TT R.A.: 10h09m05.215s DE441 (CdC)
DEC : 10°35’15.12”
R.A.: 10h09m05.214537s DE441 JPL HORIZONS ΔT=14.641s
DEC : 10°35’15.12443”
R.A.: 10h09m05.222s INPOP21a (CdC)
DEC : 10°35’15.10”
Date: 1800-Aug-15 0h TT R.A.: 05h25m47.792s DE441 (CdC)
DEC : 27°37’01.42”
R.A.: 05h25m47.791855s DE441 JPL HORIZONS ΔT=18.401s
DEC : 27°37’01.422”
R.A.: 05h25m47.794s INPOP21a (CdC)
DEC : 27°37’01.42”
Date: 2000-Aug-15 0h TT R.A.: 21h32m46.319s DE441 (CdC)
DEC : -16°56’33.91”
R.A.: 21h32m46.318801s DE441 JPL HORIZONS ΔT=64.183s
DEC : -16°56’33.90793”
R.A.: 21h32m46.319s INPOP21a (CdC)
DEC : -16°56’33.91”
Date: 3000-Aug-15 0h TT R.A.: 02h13m53.334s DE441 (CdC)
DEC : 11°42’06.18”
R.A.: 02h13m53.333587s DE441 JPL HORIZONS ΔT=69.183s
DEC : 11°42’06.17771”
R.A.: 21h32m53.074s INPOP21a (CdC)
DEC : 11°42’05.35”
As can be seen, INPOP21a differs most from DE441 at both extremes of the interval from J2000.0.
Interestingly, the beginning of the interval in the past shows a much larger difference than the final limit in the future.
Regards
For the date 1600… the declension includes
DEC : -18°26’52.61″ INPOP21a (CdC)
I’m sorry.
Thank you very much Kamil for this interesting comparative table.
Using INPOP19a for 1000-Aug-15 0h TT : https://ssp.imcce.fr/forms/ephemeris
R.A. : 20h48m09.2773s
DEC : -23°09′30.154″
R.A.: 20h48m09.068s INPOP21a (CdC)
DEC : -23°09’31.02”
So INPOP21a seems consistent with INPOP19a.
I agree about the difference between INPOP21a and DE441 at the beginning of the period.
Hard to say who is right : IMCCE or JPL… not me anyway.
Regards
Thank you Bercu for the planets,
the difference is not as great as for the moon.
SATURN
Using INPOP21a for 1000-Aug-15 0h TT: (CdC)
R.A. : 05h23m02.941s
DEC : +21°34′17.55″
R.A. : 05h23m02.975s INPOP19a (CdC)
DEC : +21°34′17.59″
R.A. : 05h23m02.973s DE441 (CdC)
DEC : +21°34′17.59″
R.A. : 05h23m02.972832s DE441 JPL HORIZONS
DEC : +21°34′17.59133″
Regards
Thank you Kamil.
Unfortunately we cannot compute the Moon position before AD 1000 with INPOP.
It would have been interesting to compare INPOP21a and DE441 several thousand years ago.
Regards