Please place here comments about bugs of the current version. I’ll do the same.
This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Read More
I consent to the use of following cookies:
Necessary cookies help make a website usable by enabling basic functions like page navigation and access to secure areas of the website. The website cannot function properly without these cookies.
We do not use cookies of this type.
Marketing cookies are used to track visitors across websites. The intention is to display ads that are relevant and engaging for the individual user and thereby more valuable for publishers and third party advertisers.
We do not use cookies of this type.
Analytics cookies help website owners to understand how visitors interact with websites by collecting and reporting information anonymously.
We do not use cookies of this type.
Preference cookies enable a website to remember information that changes the way the website behaves or looks, like your preferred language or the region that you are in.
We do not use cookies of this type.
Unclassified cookies are cookies that we are in the process of classifying, together with the providers of individual cookies.
We do not use cookies of this type.
Cookies are small text files that can be used by websites to make a user's experience more efficient. The law states that we can store cookies on your device if they are strictly necessary for the operation of this site. For all other types of cookies we need your permission. This site uses different types of cookies. Some cookies are placed by third party services that appear on our pages.
Hi
Just downloaded version 473R. Great work as usual.
I check the total solar eclipse observed in Babylon 15 April 136BC with Earth static Mercator view. The path of the eclipse is correct. However at the top of the map (Mercator view), there is an horizontal line (same width and colors used for the path of the eclipse). This line is not shown for the 3 June 1239 solar eclipse for instance. Is this line an artefact due to my graphic card or is there another explanation ?
Anyway the latest version is running fine on my computer.
Best regards.
Hi,
it’s a bug, due to the fact that lines going from longitudes +180° to -179°, trespassing the right side of the map, try to connect themselves in the wrong way, and vice versa. It’s an effect similar to the cart on old typewriters. 🙂 I’ll fix that.
regards
A.C.
Anch’io l’ho scaricata, con grande soddisfazione, e confermo il bug segnalato da Bercu, verificando una eclissi anulare del 1718 BCE. In quella circostanza il Delta T riportato da Uruk-One è = 40474.5 sec., mentre Espenak dichiara 39821 sec.
Cordiali saluti
L.Torlai
Sì, su quel bug non ci piove, ho già risolto il problema con il nuovo codice. Ovviamente Espenak basa i suoi calcoli sugli algoritmi pubblicati dalla NASA, tanto è vero che se prova a settare Uruk_One su NASA per quanto riguarda il DeltaT otterrà esattamente lo stesso valore. Si tratta di una funzione parabolica che però tiene conto solo degli effetti mareali sulla rotazione terrestre. In realtà accade che iterazioni tra il nucleo fluido terrestre (la parte più esterna del nucleo) e il mantello nonché la variazione di frizione sulle coste di masse oceaniche liquide che sono andate aumentando o diminuendo nel corso dei secoli a causa di piccole glaciazioni abbia creato delle discontinuità, che sto cercando di verificare basandomi su osservazioni antiche di eclissi solari o lunari. Da qui nascono i punti di calibrazione che ho istituito e il valore cosiddetto “RC” che in genere applico.
La saluto cordialmente
A.C.
Hi
I am testing the new version and the new improvements are very useful.
Great to see the location names on the Earth map when zooming.
In a future version, do you think it is possible to add the reference for DE440 and 441 (info tab) as Uruk_One no longer uses DE430 and 431 :
The JPL Planetary and Lunar Ephemerides DE440 and DE441, Ryan S. Park et al 2021 AJ 161 105
Thank you.
Regards
Hi Bercu,
thanks for the info. I forgot to add the due reference to S.Park and his team. Just added.
regards
A.C.
Hi
The bug I reported concerned the calculation of delta T by IMCCE and not by Uruk_One. Moreover, IMCCE replied that an update will be implemented, taking into account the article published by Stephenson et al. in 2021. Fred Espenak uses values of delta T from Morrison, L. and Stephenson, F. R., “Historical Values of the Earth’s Clock Error ΔT and the Calculation of Eclipses”, J. Hist. Astron., Vol. 35 Part 3, August 2004, No. 120, pp 327-336 (2004).
I think it is very difficult to compute delta T in the past.
Now a new article by Andre Maeder, Geneva Observatory, and al. 29 October 2021 (https://link.springer.com/article/10.1007/s10509-021-04004-7) specifies “The observations of lunar occultations completed by the IERS data show for the period from 1680 to 2020 AD a variation rate of the LOD equal to 1.09 ms/cy. This rate is in agreement with the results of McCarthy and Babcock (1986) and Sidorenkov (2005). The above rate is lower than the mean of 1.78 ms/cy derived on the basis of the data for eclipses from the Antiquity to 1600 AD by Stephenson et al. (2016).
Regards
Hi,
actually Mr. Torlai was referring to the graphical bug related to the Mercator map. With regard to the estimates of the deltaT there’s a headache to come….. 🙂
regards
A.C.