any good introduction on Astronomical Ephemeris?
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I want to create a program for Astronomical Ephemeris, but I don't know much about it. My real intention is to understand this software astrolog at this Any recommendations on some quick tutorials on this topic?
diligent hands rule....
You need to understand the file format. I converted their programs from c and doubles, to c# and decimals a few years back. Government software is mostly in the public domain; I tried a few until it matched the observatories and Chinese calendars. [Format of the JPL Ephemeris Files](https://www.celestialprogramming.com/jpl-ephemeris-format/jpl-ephemeris-format.html)
"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I
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Stellarium (stellarium.org) has an observability plugin you might be interested in. I haven't used it, so cannot comment further.
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
I regularly use Stellarium from Portable Apps website. It is pretty straight forward but user interface is a little difficult at first. When you initially run it, it starts slow but be patient. When it first comes up it will be full screen. If move the mouse to bottom of window a popup will display some options. Move cursor all the way to left corner. Another vertical menu will pop up. Select the top of the menu to get to the location specification interface. It's tricky, but you can enter your location by city name. Move cursor to bottom again, horizontal menu comes up. On the right is date and time scroll buttons. It's a great tool. And I have confirmed its star and moon locations by going outside and observing them. To end the program hit the power button on far right of lower horizontal menu.
"A little time, a little trouble, your better day" Badfinger
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I regularly use Stellarium from Portable Apps website. It is pretty straight forward but user interface is a little difficult at first. When you initially run it, it starts slow but be patient. When it first comes up it will be full screen. If move the mouse to bottom of window a popup will display some options. Move cursor all the way to left corner. Another vertical menu will pop up. Select the top of the menu to get to the location specification interface. It's tricky, but you can enter your location by city name. Move cursor to bottom again, horizontal menu comes up. On the right is date and time scroll buttons. It's a great tool. And I have confirmed its star and moon locations by going outside and observing them. To end the program hit the power button on far right of lower horizontal menu.
"A little time, a little trouble, your better day" Badfinger
If you have a tracking telescope, Stellarium can control it for you. It is extremely powerful, and good enough for archaeoastronomy work. You can see some of it's archaeoastronomy abilities in the 'Our Forgotten Astronomy' link in my signature, if you are interested in such endeavors.
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
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If you have a tracking telescope, Stellarium can control it for you. It is extremely powerful, and good enough for archaeoastronomy work. You can see some of it's archaeoastronomy abilities in the 'Our Forgotten Astronomy' link in my signature, if you are interested in such endeavors.
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
I do not have a tracking telescope. Glad that Stellarium has such a feature. I have listened to some of your lectures about history, astronomy and religion. Pretty complicated but interesting about the links. Funny how the stars and our lives can get intermixed. I remember seeing Haley's comet "many moons ago", one of my favorite expressions. Thanx
"A little time, a little trouble, your better day" Badfinger
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I do not have a tracking telescope. Glad that Stellarium has such a feature. I have listened to some of your lectures about history, astronomy and religion. Pretty complicated but interesting about the links. Funny how the stars and our lives can get intermixed. I remember seeing Haley's comet "many moons ago", one of my favorite expressions. Thanx
"A little time, a little trouble, your better day" Badfinger
My favorite will always be the night I got to watch the Northern Lights almost all night long. I've only seen them that once - Incredible!
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
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I want to create a program for Astronomical Ephemeris, but I don't know much about it. My real intention is to understand this software astrolog at this Any recommendations on some quick tutorials on this topic?
diligent hands rule....
Agree specially if you have been working with all of your effort but still no one appreciate it. 스포츠중계
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My favorite will always be the night I got to watch the Northern Lights almost all night long. I've only seen them that once - Incredible!
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
I have seen Aurora Borealis multiple times. In Canada and U.S. The last were huge white curtains with tinge of green that lasted for hours. I was told it happens quite often at northerly latitudes above 50 deg. BTW Aurora Australis is the southern latitude version. Not seen those. Enjoyed your discussion on the potential roots of the Samson story.
"A little time, a little trouble, your better day" Badfinger
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I have seen Aurora Borealis multiple times. In Canada and U.S. The last were huge white curtains with tinge of green that lasted for hours. I was told it happens quite often at northerly latitudes above 50 deg. BTW Aurora Australis is the southern latitude version. Not seen those. Enjoyed your discussion on the potential roots of the Samson story.
"A little time, a little trouble, your better day" Badfinger
Mine were green and red sheets, dancing all night. Little to no white. It was amazing!
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
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Mine were green and red sheets, dancing all night. Little to no white. It was amazing!
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
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I have written several ephemerides over the years, the first being for an HP75C, using the 'Low-precision formulae for planetary positions' by van Flandern and Pulkkinen (Astrophysical Journal Supplement Series, vol. 41, Nov. 1979, p. 391-411). The paper provides a good introduction to the general problems of ephemerides, and the stated accuracy of +/- one minute of arc is extremely conservative, and for the current era +/- six seconds of arc is realistic. This ephemeris also calculates the 'First point of Ares', enabling star positions to be computed. I used this method to navigate my small yacht by sextant from Southampton UK to Pireaus Greece, with my worst landfall being one third of a nautical mile out. That was in pre-GPS days. A more accurate methodology, but also much more compute intensive, is Pierre Bretagnon's VSOP82, subsequently developed and refined to VSOP87. The raw data tables which make the basis for the computations are out there on the web somewhere, I'm sure. When written into a program, it is spritely enough on a PC, but might tax all but top-end mobile devices. A very good source of foundational information is the US Navy's Nautical Almanac, particularly in the 'Explanatory Supplement', a separate publication. Any year will do. Also, get a thorough understanding of the 'equation of time', as it occurs in just about every ephemeris calculation. A couple of years ago I rewrote my original HP75C program to run on Android, and expanded it to cover not just the sun, moon, six navigational planets, fifty-eight navigational stars and Polaris, but included all ten thousand stars visible to the naked eye (given very good eyes and excellent viewing conditions :-\ ). Even on an old Android phone it runs fast enough to be useful, although the virtual graphical sextant 'scope view is distinctly laggardly when scanning the sky.
thank you! all these sources are very useful for me.
diligent hands rule....
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You need to understand the file format. I converted their programs from c and doubles, to c# and decimals a few years back. Government software is mostly in the public domain; I tried a few until it matched the observatories and Chinese calendars. [Format of the JPL Ephemeris Files](https://www.celestialprogramming.com/jpl-ephemeris-format/jpl-ephemeris-format.html)
"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I
just be curious: why do you check that it meets Chinese calendar? also I want to convert this astrolog program to C#, but I think it is too complex for my needs...
diligent hands rule....
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Stellarium (stellarium.org) has an observability plugin you might be interested in. I haven't used it, so cannot comment further.
Our Forgotten Astronomy | Object Oriented Programming with C++ | Wordle solver
thank you!:rose:
diligent hands rule....