From: Ivan Marti-V. <i.m...@go...> - 2012-05-07 09:13:07
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Dear all, By the way, I would like to ask you if someone has considered the possibility of using the ephemeris files from the Jet Propulsion Laboratory in Stellarium. These files are given for free and are extremely precise (e.g., they consider the orbital precessions due to Relativity, perturbations between the planets, and so on). Also, the algorithms to compute planets positions from the provided tables are *extremely* fast. I used these ephemeris for my works on Astrometry and I am very happy of them. I think that a good choice for Stellarium would be the ephemeris DE423 (which run from year 1799 to year 2200). Out of this ephemeris time range, we could come back to the predictions by the plain Kepler's equations. Of course, I would be glad to help with the implementation of the new code in the core, if you would be interested. Best Wishes! Ivan |
From: Alexander W. <ale...@gm...> - 2012-05-10 02:55:55
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Hi! 2012/5/7 Ivan Marti-Vidal <i.m...@go...>: > I used these ephemeris for my works on Astrometry and I am very happy of > them. I think that a good choice for Stellarium would be the ephemeris DE423 > (which run from year 1799 to year 2200). Out of this ephemeris time range, > we could come back to the predictions by the plain Kepler's equations. DE423 run from year 1800 to year 2200 and have 36 Mb. More correct use for Stellarium DE422 because this DE run year -3000 to year 3000 and our planetarium used archeoastronomers too. But size DE422 are 532 Mb. This ephemeris may be used only as pluggable module. -- With best regards, Alexander |
From: JBerthier <ber...@im...> - 2012-05-10 06:49:57
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Hi, If you are interested I can provide the files of coefficients of the new VSOP analytical planetary theory (Stellarium uses VSOP87 until now, right?). But I'm not qualified to write any code for stellarium. The advantage of an analytical theory is that there's almost no limit in time. cheers, jerome > Hi! > > 2012/5/7 Ivan Marti-Vidal<i.m...@go...>: >> I used these ephemeris for my works on Astrometry and I am very happy of >> them. I think that a good choice for Stellarium would be the ephemeris DE423 >> (which run from year 1799 to year 2200). Out of this ephemeris time range, >> we could come back to the predictions by the plain Kepler's equations. > > DE423 run from year 1800 to year 2200 and have 36 Mb. More correct use > for Stellarium DE422 because this DE run year -3000 to year 3000 and > our planetarium used archeoastronomers too. But size DE422 are 532 Mb. > > This ephemeris may be used only as pluggable module. > -- --- Dr. Jerome Berthier ------------------ Phone: +33 (0)14051 2261 -- Institut de mecanique celeste Fax: +33 (0)14633 2834 -- 77 av. Denfert Rochereau Mailto:jer...@im... -- --- 75014 Paris - France --------------------- http://www.imcce.fr/ -- |
From: Alexander W. <ale...@gm...> - 2012-05-10 07:17:55
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Hi Jerome! 2012/5/10 JBerthier <ber...@im...>: > If you are interested I can provide the files of coefficients of the new > VSOP analytical planetary theory (Stellarium uses VSOP87 until now, > right?). But I'm not qualified to write any code for stellarium. The > advantage of an analytical theory is that there's almost no limit in time. Yes, VSOP87 used by Stellarium until now and we interested to getting new coefficients for the new VSOP analytical planetary theory. Maybe we can get this files from ftp.imcce.fr? -- With best regards, Alexander |
From: JBerthier <ber...@im...> - 2012-05-10 07:38:52
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On 05/10/2012 09:17 AM, Alexander Wolf wrote: > Hi Jerome! > > 2012/5/10 JBerthier<ber...@im...>: >> If you are interested I can provide the files of coefficients of the new >> VSOP analytical planetary theory (Stellarium uses VSOP87 until now, >> right?). But I'm not qualified to write any code for stellarium. The >> advantage of an analytical theory is that there's almost no limit in time. > Yes, VSOP87 used by Stellarium until now and we interested to getting > new coefficients for the new VSOP analytical planetary theory. Maybe > we can get this files from ftp.imcce.fr? > I'm not sure that it's already available on our ftp server. If not, I will ask my colleague to put the files on the ftp. But as I used it, I can send you an archive. cheers, jerome -- --- Dr. Jerome Berthier ------------------ Phone: +33 (0)14051 2261 -- Institut de mecanique celeste Fax: +33 (0)14633 2834 -- 77 av. Denfert Rochereau Mailto:jer...@im... -- --- 75014 Paris - France --------------------- http://www.imcce.fr/ -- |
From: Georg Z. <geo...@un...> - 2012-05-10 07:59:17
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Hi! As far as I know, also the VSOP87 has a temporal limitation and was derived to provide good results for about the years -4000...+8000. But I don't know the exact behaviour, i.e. how fast it diverges from nature beyond that range. Or can you please define "almost no limit"? An improved VSOP solution with known behaviour and longer range of validity would be very fine, but also a connection (plugin/optional data file) with DE423 for the present, and any long-term variant for historical applications, would be fine! There was a DE408 that covers years -10000...10000 (I think) as extension of DE406, however it has not been formally published (?) Also, reference frames and Earth's rotational behaviour (DeltaT, obliquity, precession, nutation, ...) must all reliably fit together to make sense of the higher accuracy. Kind regards, Georg On Do, 10.05.2012, 09:38, JBerthier wrote: > On 05/10/2012 09:17 AM, Alexander Wolf wrote: >> Hi Jerome! >> >> 2012/5/10 JBerthier<ber...@im...>: >>> If you are interested I can provide the files of coefficients of the >>> new >>> VSOP analytical planetary theory (Stellarium uses VSOP87 until now, >>> right?). But I'm not qualified to write any code for stellarium. The >>> advantage of an analytical theory is that there's almost no limit in >>> time. >> Yes, VSOP87 used by Stellarium until now and we interested to getting >> new coefficients for the new VSOP analytical planetary theory. Maybe >> we can get this files from ftp.imcce.fr? >> > > I'm not sure that it's already available on our ftp server. If not, I > will ask my colleague to put the files on the ftp. But as I used it, I > can send you an archive. > cheers, > jerome > > -- > --- Dr. Jerome Berthier ------------------ Phone: +33 (0)14051 2261 -- > Institut de mecanique celeste Fax: +33 (0)14633 2834 -- > 77 av. Denfert Rochereau Mailto:jer...@im... -- > --- 75014 Paris - France --------------------- http://www.imcce.fr/ -- > > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Stellarium-pubdevel mailing list > Ste...@li... > https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel > -- DI Dr Georg Zotti LBI ArchPro Franz-Klein-Gasse 1/III A-1190 Wien |
From: Gour <go...@at...> - 2012-05-10 09:15:33
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On Mon, 7 May 2012 11:13:01 +0200 Ivan Marti-Vidal <i.m...@go...> wrote: > By the way, I would like to ask you if someone has considered the > possibility of using the ephemeris files from the Jet Propulsion > Laboratory in Stellarium. These files are given for free and are > extremely precise (e.g., they consider the orbital precessions due to > Relativity, perturbations between the planets, and so on). Also, the > algorithms to compute planets positions from the provided tables are > *extremely* fast. May I suggest using Swiss Ephmeris library: http://www.astro.com/swisseph/swephinfo_e.htm?lang=e ...using less space than JPL (they're compressed) and there are even Moshier algorithms included which do not require ephemeris data. Sincerely, Gour -- Therefore, without being attached to the fruits of activities, one should act as a matter of duty, for by working without attachment one attains the Supreme. http://atmarama.net | Hlapicina (Croatia) | GPG: 52B5C810 |
From: Georg Z. <geo...@un...> - 2012-05-10 09:33:57
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Even though they used DE405/406, I feel uneasy when I read its target audience: "The Swiss Ephemeris is not a product for end users. It is a toolset for programmers to build into their astrological software." Just my 0.02... G. On Do, 10.05.2012, 11:15, Gour wrote: > On Mon, 7 May 2012 11:13:01 +0200 > Ivan Marti-Vidal <i.m...@go...> > wrote: > >> By the way, I would like to ask you if someone has considered the >> possibility of using the ephemeris files from the Jet Propulsion >> Laboratory in Stellarium. These files are given for free and are >> extremely precise (e.g., they consider the orbital precessions due to >> Relativity, perturbations between the planets, and so on). Also, the >> algorithms to compute planets positions from the provided tables are >> *extremely* fast. > > May I suggest using Swiss Ephmeris library: > > http://www.astro.com/swisseph/swephinfo_e.htm?lang=e > > ...using less space than JPL (they're compressed) and there are even > Moshier algorithms included which do not require ephemeris data. > > > Sincerely, > Gour > > -- > Therefore, without being attached to the fruits of activities, > one should act as a matter of duty, for by working without > attachment one attains the Supreme. > > http://atmarama.net | Hlapicina (Croatia) | GPG: 52B5C810 > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. > http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/_______________________________________________ > Stellarium-pubdevel mailing list > Ste...@li... > https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel > |
From: Thomas M. <tom...@gm...> - 2012-05-10 09:55:48
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I share Georg's feeling on this. The Swiss Ephemeris website seems to be targeted towards an astrological audience rather than an astronomical one. Thanks, Thomas On 10 May 2012 10:33, Georg Zotti <geo...@un...> wrote: > Even though they used DE405/406, I feel uneasy when I read its target > audience: > > "The Swiss Ephemeris is not a product for end users. It is a toolset for > programmers to build into their astrological software." > > > Just my 0.02... > > G. > > On Do, 10.05.2012, 11:15, Gour wrote: >> On Mon, 7 May 2012 11:13:01 +0200 >> Ivan Marti-Vidal <i.m...@go...> >> wrote: >> >>> By the way, I would like to ask you if someone has considered the >>> possibility of using the ephemeris files from the Jet Propulsion >>> Laboratory in Stellarium. These files are given for free and are >>> extremely precise (e.g., they consider the orbital precessions due to >>> Relativity, perturbations between the planets, and so on). Also, the >>> algorithms to compute planets positions from the provided tables are >>> *extremely* fast. >> >> May I suggest using Swiss Ephmeris library: >> >> http://www.astro.com/swisseph/swephinfo_e.htm?lang=e >> >> ...using less space than JPL (they're compressed) and there are even >> Moshier algorithms included which do not require ephemeris data. >> >> >> Sincerely, >> Gour >> >> -- >> Therefore, without being attached to the fruits of activities, >> one should act as a matter of duty, for by working without >> attachment one attains the Supreme. >> >> http://atmarama.net | Hlapicina (Croatia) | GPG: 52B5C810 >> ------------------------------------------------------------------------------ >> Live Security Virtual Conference >> Exclusive live event will cover all the ways today's security and >> threat landscape has changed and how IT managers can respond. Discussions >> will include endpoint security, mobile security and the latest in malware >> threats. >> http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/_______________________________________________ >> Stellarium-pubdevel mailing list >> Ste...@li... >> https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel >> > > > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Stellarium-pubdevel mailing list > Ste...@li... > https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel |
From: Gour <go...@at...> - 2012-05-10 10:46:53
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On Thu, 10 May 2012 10:55:37 +0100 Thomas Morris <tom...@gm...> wrote: > I share Georg's feeling on this. The Swiss Ephemeris website seems to > be targeted towards an astrological audience rather than an > astronomical one. Have you, at least, tried to read these few paragraphs: The Swiss Ephemeris is based upon the latest planetary and lunar ephemeris, DE405/406, developed by NASA's Jet Propulsion Laboratory. The original integration, DE405, covered the years 3000 BC to 3000 AD and required 550 Mb of disk space. DE406 is a compressed version of DE405 which requires 200 MB while maintaining a precision of better than 1 m for the moon and 25 m for the planets. These data have been further compressed with sophisticated compression techniques developed by Astrodienst. The ephemeris now requires for the complete 6000 years only 5 Mb for all planets except the Moon, and 13 Mb for the Moon. This compressed ephemeris reproduces the JPL data with 0.001 arcseconds precision. We have extended the timespan of the JPL ephemeris by numerical integration, so that Swiss Ephemeris covers the years 5400 BC to 5400 AD, a total of 10'800 years. For this extended timespan the ephemeris requires 32 Mbytes of ephemeris files. All transformation steps from the inertial timeframe of the JPL DE406 integration to the reference frame for astrological coordinates (true equinox of date), all corrections like relativistic aberration, deflection of light in the gravity field of the Sun etc. have been performed with utmost care and precision so that the target precision of 0.001 arcsec is maintained through all transformation steps. Never before has such a high precision ephemeris been available to astrologers. Swiss Ephemeris contains three ephemerides. The user can choose whether he/she wants to use the original JPL DE406 data (if available at his/her site), the compressed Swiss Ephemeris data (the default) or a built in semianalytic theory by Steve Moshier. The Swiss Ephemeris package switches automatically to the available best precision ephemeris dependent on which installed ephemeris files it finds. Even without any stored ephemeris files, using the Moshier model, planetary positions with better than 0.1 seconds of arc precision are available (3 arcsec for the Moon). or it is just prejudice considering that astronomy & astrology does not have anything in common? Sincerely, Gour -- As a strong wind sweeps away a boat on the water, even one of the roaming senses on which the mind focuses can carry away a man's intelligence. http://atmarama.net | Hlapicina (Croatia) | GPG: 52B5C810 |
From: Thomas M. <tom...@gm...> - 2012-05-10 12:11:52
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Hi Gour, Yes, I did read the information you have quoted. I agree that the Swiss Ephemeris looks useful to Stellarium and has a compatible (GPL) license. However, as a trained research scientist I am very fussy about sources and accuracy and I would like to see at minimum a peer-reviewed paper discussing the extension of the JPL ephemeris and discussion of algorithms used both in the integration and the data compression. Thanks, Thomas On 10 May 2012 11:46, Gour <go...@at...> wrote: > On Thu, 10 May 2012 10:55:37 +0100 > Thomas Morris <tom...@gm...> > wrote: > >> I share Georg's feeling on this. The Swiss Ephemeris website seems to >> be targeted towards an astrological audience rather than an >> astronomical one. > > Have you, at least, tried to read these few paragraphs: > > The Swiss Ephemeris is based upon the latest planetary and lunar > ephemeris, DE405/406, developed by NASA's Jet Propulsion Laboratory. The > original integration, DE405, covered the years 3000 BC to 3000 AD and > required 550 Mb of disk space. DE406 is a compressed version of DE405 > which requires 200 MB while maintaining a precision of better than 1 m > for the moon and 25 m for the planets. These data have been further > compressed with sophisticated compression techniques developed by > Astrodienst. The ephemeris now requires for the complete 6000 years only > 5 Mb for all planets except the Moon, and 13 Mb for the Moon. This > compressed ephemeris reproduces the JPL data with 0.001 arcseconds > precision. > > We have extended the timespan of the JPL ephemeris by numerical > integration, so that Swiss Ephemeris covers the years 5400 BC to 5400 > AD, a total of 10'800 years. For this extended timespan the ephemeris > requires 32 Mbytes of ephemeris files. > > All transformation steps from the inertial timeframe of the JPL DE406 > integration to the reference frame for astrological coordinates (true > equinox of date), all corrections like relativistic aberration, > deflection of light in the gravity field of the Sun etc. have been > performed with utmost care and precision so that the target precision of > 0.001 arcsec is maintained through all transformation steps. Never > before has such a high precision ephemeris been available to > astrologers. > > Swiss Ephemeris contains three ephemerides. The user can choose whether > he/she wants to use the original JPL DE406 data (if available at his/her > site), the compressed Swiss Ephemeris data (the default) or a built in > semianalytic theory by Steve Moshier. The Swiss Ephemeris package > switches automatically to the available best precision ephemeris > dependent on which installed ephemeris files it finds. Even without any > stored ephemeris files, using the Moshier model, planetary positions > with better than 0.1 seconds of arc precision are available (3 arcsec > for the Moon). > > > or it is just prejudice considering that astronomy & astrology does not > have anything in common? > > > Sincerely, > Gour > > -- > As a strong wind sweeps away a boat on the water, > even one of the roaming senses on which the mind > focuses can carry away a man's intelligence. > > http://atmarama.net | Hlapicina (Croatia) | GPG: 52B5C810 > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Stellarium-pubdevel mailing list > Ste...@li... > https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel > |
From: Alexander W. <ale...@gm...> - 2012-05-10 12:17:09
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Hi Jerome! 2012/5/10 JBerthier <ber...@im...>: > I'm not sure that it's already available on our ftp server. If not, I > will ask my colleague to put the files on the ftp. But as I used it, I > can send you an archive. For note - which VSOP you use - 2000, 2002, 2002b or 2004? -- With best regards, Alexander |
From: JBerthier <ber...@im...> - 2012-05-12 15:25:59
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On 05/10/2012 02:16 PM, Alexander Wolf wrote: > Hi Jerome! > > 2012/5/10 JBerthier<ber...@im...>: >> I'm not sure that it's already available on our ftp server. If not, I >> will ask my colleague to put the files on the ftp. But as I used it, I >> can send you an archive. > For note - which VSOP you use - 2000, 2002, 2002b or 2004? > The latest was VSOP09 (2009), but the final version should be published soon. jerome -- --- Dr. Jerome Berthier ------------------ Phone: +33 (0)14051 2261 -- Institut de mecanique celeste Fax: +33 (0)14633 2834 -- 77 av. Denfert Rochereau Mailto:jer...@im... -- --- 75014 Paris - France --------------------- http://www.imcce.fr/ -- |
From: Gour <go...@at...> - 2012-05-10 12:59:53
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On Thu, 10 May 2012 13:11:40 +0100 Thomas Morris <tom...@gm...> wrote: Hello Thomas, > However, as a trained research scientist I am very fussy about sources > and accuracy and I would like to see at minimum a peer-reviewed paper > discussing the extension of the JPL ephemeris and discussion of > algorithms used both in the integration and the data compression. Good. Download Swiss Ephemeris lib, run make and then test results using swetest program against JPL data. (there are ready-made executables if you're on Windows) ;) Or even simpler, you can download calculated Ephemeris data from http://www.astro.com/swisseph/swepha_e.htm and compare. Sincerely, Gour -- The senses are so strong and impetuous, O Arjuna, that they forcibly carry away the mind even of a man of discrimination who is endeavoring to control them. http://atmarama.net | Hlapicina (Croatia) | GPG: 52B5C810 |
From: JBerthier <ber...@im...> - 2012-05-12 15:25:04
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Hi, > As far as I know, also the VSOP87 has a temporal limitation and was > derived to provide good results for about the years -4000...+8000. But I > don't know the exact behaviour, i.e. how fast it diverges from nature > beyond that range. Or can you please define "almost no limit"? "Almost no limit" in the sense that the accuracy of the trigonometric series (which define the elements of the theory) is timeless (e.g. truncature at 10.e-15 for the best accuracy). So you can compute the position of a planet at any epoch. But if you want to compare that position to the actual position of the planet ... it's an issue. From a strict scientifical point of view, it is impossible, because we don't have direct measurements to compare to the elements of the theory (e.g. a direct measure of the Earth-Sun distance doesn't exist). That means that the comparaison must be done on derived measurements, which have themselves errors. The VSOP theory can be used on the period -10000 ... +10000 with the lowest level of uncertainty one can expect to have. For this time span, there's also the numerical solution named INPOP (http://www.imcce.fr/inpop/), which is handled by the Calceph library (http://www.imcce.fr/inpop/calceph/index.php) (which handle also JPL's DExxx solutions), as well JPL's solutions. Both VSOP and INPOP provide ephemeris of planets with respect to the ICRF. For ephemeris calculation on a larger period of time (tens of thousand to millions of years), it exists dedicated planetary theory such as TOP82 (and newest version), usually limited to the motion of the 4 main planets (http://adsabs.harvard.edu/full/1983A%26A...120..197S). cheers, jerome -- --- Dr. Jerome Berthier ------------------ Phone: +33 (0)14051 2261 -- Institut de mecanique celeste Fax: +33 (0)14633 2834 -- 77 av. Denfert Rochereau Mailto:jer...@im... -- --- 75014 Paris - France --------------------- http://www.imcce.fr/ -- |
From: Georg Z. <geo...@un...> - 2012-05-13 19:52:55
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Dear Jerome, thanks for the info and links, looks interesting! Kind regards, Georg On Sa, 12.05.2012, 17:24, JBerthier wrote: > Hi, > >> As far as I know, also the VSOP87 has a temporal limitation and was >> derived to provide good results for about the years -4000...+8000. But I >> don't know the exact behaviour, i.e. how fast it diverges from nature >> beyond that range. Or can you please define "almost no limit"? > > "Almost no limit" in the sense that the accuracy of the trigonometric > series (which define the elements of the theory) is timeless (e.g. > truncature at 10.e-15 for the best accuracy). So you can compute the > position of a planet at any epoch. But if you want to compare that > position to the actual position of the planet ... it's an issue. From a > strict scientifical point of view, it is impossible, because we don't > have direct measurements to compare to the elements of the theory (e.g. > a direct measure of the Earth-Sun distance doesn't exist). That means > that the comparaison must be done on derived measurements, which have > themselves errors. > > The VSOP theory can be used on the period -10000 ... +10000 with the > lowest level of uncertainty one can expect to have. For this time span, > there's also the numerical solution named INPOP > (http://www.imcce.fr/inpop/), which is handled by the Calceph library > (http://www.imcce.fr/inpop/calceph/index.php) (which handle also JPL's > DExxx solutions), as well JPL's solutions. > > Both VSOP and INPOP provide ephemeris of planets with respect to the ICRF. > > For ephemeris calculation on a larger period of time (tens of thousand > to millions of years), it exists dedicated planetary theory such as > TOP82 (and newest version), usually limited to the motion of the 4 main > planets (http://adsabs.harvard.edu/full/1983A%26A...120..197S). > > cheers, > jerome > > -- > --- Dr. Jerome Berthier ------------------ Phone: +33 (0)14051 2261 -- > Institut de mecanique celeste Fax: +33 (0)14633 2834 -- > 77 av. Denfert Rochereau Mailto:jer...@im... -- > --- 75014 Paris - France --------------------- http://www.imcce.fr/ -- > > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Stellarium-pubdevel mailing list > Ste...@li... > https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel > -- DI Dr Georg Zotti LBI ArchPro Franz-Klein-Gasse 1/III A-1190 Wien |