Gaugamela eclipse on your desktop?

[marcus]

Hello all.I was listening to a very interesting programme on the radio yesterday, in which someone had asked a question about a rare conjunction of planets in the late 18th century. They wheeled on some astonomy professor, who explained that one can get software that allows you to gain a view of the night sky at any point in history, and I believe from any point on earth. Apparently this is available for one's home PC.It seemed a bit far-fetched ... but obviously, it being Radio 4, it must have been correct (or I had misunderstood).So, the question is: is anyone aware of the existence of this software? If so, I am assuming that one would be able to tap in the date of the eclipse that preceded Gaugamela, and 'see' the same night-sky that Alexander and his army did.ATBMarcus

[amyntoros]

Well, I found a couple of sites on this. http://www.starrynight.com/support/prod ... kstars/The first has software for sale that can do the task (and many others) and the second has a free download. However, any site that includes expressions such as "independent tarball of the KStars code" is just guaranteed to scare me away. And the fact that, on my computer at least, the left side of some of the text disappears into white space doesn't exactly inspire my confidence in their software. Then again, maybe one of our members is a computer geek who understands all this and would like to give it a try. I think I'll stick with my self-made Webshots screensaver of Alexander images. :-)Best regards,Amyntoros

[amyntoros]

Well, I found a couple of sites on this. http://www.starrynight.com/support/prod ... kstars/The first has software for sale that can do the task (and many others) and the second has a free download. However, any site that includes expressions such as "independent tarball of the KStars code" is just guaranteed to scare me away. And the fact that, on my computer at least, the left side of some of the text disappears into white space doesn't exactly inspire my confidence in their software. Then again, maybe one of our members is a computer geek who understands all this and would like to give it a try. I think I'll stick with my self-made Webshots screensaver of Alexander images. :-)Best regards,Amyntoros

[Taphoi]

The matter is far less straightforward than you might think. Firstly, Lunar eclipses are quite common (around two per year, if partial ones are included). Secondly, the Earth-Moon-Sun system behaves chaotically on long time scales. That is to say, small perturbations are readily magnified into large errors in the calculations. There is also a good possibility of unknown perturbations. For example, the close approach of an unknown comet to the Earth-Moon system could have perturbed the system, and there is some evidence for a close approach in the dark ages (forget exact date).There is a NASA catalogue of Lunar eclipses on line. It is likely that the famous one before Gaugamela is that of September 20th 331BC at 18:21UT. There is no other good candidate nearby, but the comet scenario could mean that this date/time is in error by an unknown amount.Best wishes,Andrew

[Taphoi]

The matter is far less straightforward than you might think. Firstly, Lunar eclipses are quite common (around two per year, if partial ones are included). Secondly, the Earth-Moon-Sun system behaves chaotically on long time scales. That is to say, small perturbations are readily magnified into large errors in the calculations. There is also a good possibility of unknown perturbations. For example, the close approach of an unknown comet to the Earth-Moon system could have perturbed the system, and there is some evidence for a close approach in the dark ages (forget exact date).There is a NASA catalogue of Lunar eclipses on line. It is likely that the famous one before Gaugamela is that of September 20th 331BC at 18:21UT. There is no other good candidate nearby, but the comet scenario could mean that this date/time is in error by an unknown amount.Best wishes,Andrew

[marcus]

Hmm. I did wonder if it was that straightforward, and you seem to confirm my fears. It certainly bears looking into further. I'm not sure what academic use being able to "see" the sky on that particular night would be, but it would be interesting.CheersMarcus

[marcus]

Hmm. I did wonder if it was that straightforward, and you seem to confirm my fears. It certainly bears looking into further. I'm not sure what academic use being able to "see" the sky on that particular night would be, but it would be interesting.CheersMarcus

[marcus]

Hmm, disappearing text, eh? As I'm using my mother's computer at the moment, I'm not sure I want to risk it ... but it definitely bears further investigation.Thanks, as always.Marcus

[marcus]

Hmm, disappearing text, eh? As I'm using my mother's computer at the moment, I'm not sure I want to risk it ... but it definitely bears further investigation.Thanks, as always.Marcus

[ruthaki]

I wouldn't be surprised there is some available. Once I had a question about the location of a certain constellation at a particular time for my novel. I found an astrology site, asked the question, and was amazed at the quick response. I'll see if I can find the source for this.

[ruthaki]

I wouldn't be surprised there is some available. Once I had a question about the location of a certain constellation at a particular time for my novel. I found an astrology site, asked the question, and was amazed at the quick response. I'll see if I can find the source for this.