Celestia Forums

Fresh from the press: http://www.cordis.lu/science-society/descartes/finalists2003.htm --> Pinpoint positioning in a wobbly world "This European-led international collaboration has resulted in the development of a new model for nutation (small periodic motions - 600 metres - of the Earth's axis as i...

Not that the respective people can't do it on their own, but maybe someone is still asking for this... cheers, Fotis In distfile, change this line: MD5 (celestia-1.2.5.tar.gz) = 23b525a431cf9be66f4f943c131a47bb In Makefile, change this line: PORTVERSION= 1.2.5 And fix the following 2 files # replace...

our (human race) eclipse predictions are fairly accurate, because the near-earth celestial mechanics model would be erroneous only if an event happened that gave energy to the system of planets like earth-sun-moon (and the ones nearby, truly). It requires excessive amount of energy in order to chan...

Celestia was using the VSOP87 series that gave the Earth's position referred to the ecliptic and equinox of date. In 1.2.5pre7, I changed it to the VSOP87 series referred to the J2000.0 ecliptic and equinox (which is very close to the International Celestial Reference Frame). Which series to use is...

all i'm saying is, if these 1000s-of-terms orbit remain valid over several millennia, i am nothing short of amazed. If someone has any comment on the uncertainty of our current solar system models, it would be great to present it here... It appears to me that selden had recently "accessed" such inf...

In 1.2.5 prerelease 7, I increased the accuracy of orbits even further, so you should get better results with 1.2.5. The prerelease can be found here, albeit for Windows only right now: http://www.shatters.net/celestia/files/celestia-win32-1.2.5pre7.exe --Chris Hi Chris, may I ask what kind of adju...

also, I am wondering how nasa can be so confident about plotting eclipse paths as far back as 2000 BC.... since there is no exact solution for the evolution of the solar system, and eclipses are very delicate to calculate. Eclipse events follow very regular patterns, called "saros" series and have ...

all i'm saying is, if these 1000s-of-terms orbit remain valid over several millennia, i am nothing short of amazed. FYI, I've been involved in geological projects a few times, and everything is unbelievably "linear": continent X goes to that direction with this speed, mountain Y goes there (every y...

also, I am wondering how nasa can be so confident about plotting eclipse paths as far back as 2000 BC.... since there is no exact solution for the evolution of the solar system, and eclipses are very delicate to calculate. Good question. I was wondering the same, while providing that URL on Xerxes'...

well, I must say, this is a sobering experience as far the reliability of the anglo-saxon chronicle is concerned... [...] it seems that there must have been some rough idea at least about the predictabilityof eclipses... It wasn't very unlikely: Thales of Melitus (6th century BC), had succesfully p...

Celestia 1.2.4 and before had some problems with the orbit of the Earth, and calculations for eclipses were unreliable far in the past. The latest prerelease has a fix, and I can now reproduce, for example, the path of the eclipse of Xerxes in 479 B.C.E.: http://sunearth.gsfc.nasa.gov/eclipse/SEhis...

This brings to mind, would it not make sense to display the Julian calendar for dates earlier than Oct 1582? The Gregorian dates are simply misleading. IMHO, the primary Celestia screen should stick as is currently. The reasoning behind that, is that much astronomical software is working like this,...