Take a Horizontal line,the top of your monitor, edge of a window or the horizon itself. close one eye and bring one finger in front of your face in a way that it crosses the horizontal line. close the open eye and open the other one without moving your finger. you will notice that your fingers position changes relative to the horizontal line. Each eye sees a different position of the horizontal line crossed by your finger.
we have the same phenomenon with the crossing point of moons orbit and the ecliptic. Moons orbit is very close to our eyes compared to the ecliptic (which is the suns orbit).
I don't know how exactly the Rishis wanted us to calculate the position of Rahu/Ketu but as @ernst explains astrology's roots are in observation of the astronomical events. So if we take Rahu/Ketu as an astronomical observable phenomena then this must be also true for them.
when we are considering an observable astronomical event such as an eclipse then finding Moons orbit junction with the ecliptic from the observer point of view becomes very important.
I was wondering if Kala is using Swiss ephemeris which is derived from NASA JPL ephemeris then how come Kala shows an eclipse could have happened at July 14th 1787 while NASA doesn't have it in it's data base.
I believe that for this particular date, the deference from the observer position has cause the confusion, and there was no solar eclipse on July 14th 1787.
Take a Horizontal line,the top of your monitor, edge of a window or the horizon itself. close one eye and bring one finger in front of your face in a way that it crosses the horizontal line. close the open eye and open the other one without moving your finger. you will notice that your fingers position changes relative to the horizontal line. Each eye sees a different position of the horizontal line crossed by your finger.
Correct me if I'm wrong- but I think the differing observer point would change what type of eclipse we see in the skies from a place (total, partial etc), how long it can be seen and whether or not an eclipse can even be seen from a particular position (since it can't be seen before sunrise or after sunset).
Hi @leela and thank you for your comment
You are mostly Correct. lets say there is a total eclipse occurring today around the equator somewhere in Africa. The eclipse is happening, no doubt on that. If at the same time we are in a northern latitude we will not see it. This buy itself means that the relative position of Moons orbit to the ecliptic has changed as the observer has moved north. for this eclipse if you calculate the total eclipse in Kala, you will see that the Moon/Sun conjunction is very close to Rahu/Ketu. In this case you are absolutely Correct.
If the change of Moon/Sun orbit's cross point with the change of the observers position for the same moment, should be applied to Rahu/Ketu, is a matter of definition, which I'm waiting for @ernst to come back and clear me on this.
But let's say we are talking about an eclipse in the beginning of a Saros Cycle, which is a partial eclipse just falling on the north or south pole. in this case if you calculate the moment in Kala, you will see the Sun/Moon conjunction falls about 15 degrees or more in front of one of the nodes. This is OK if we are sure the eclipse has happened, but if we are not sure, then we can not become sure of it from the data Kala is providing. more data is needed. we can not just say because the Sun/Moon conjunction is occurring on the edge of the furthest distance from the nodes where usually eclipses happen so it will happen. At this point the place of the observer as well as the 3D geometry of Sun/Moon/Earth become critical.
Please also note that every thing in astrology calculations depends on the observer point of view. lets say today Sun is in 6 degrees Virgo when you see at noon. If some one is in a Starship going towards Mars and is a few 100,000 kilometers away from earth, he will see the sun in another degree or even an other sign at the exact same time.
But we, being on earth, can only be separated around 12,000 Kilometers (straight line) at a specific moment. well the question is how much a difference dose it make and is it worth calculating or not.
I calculated the approximate maximum difference in the angle of view of 2 observers at opposite sides of earth one seeing the moon rise and the other the moon set at the same moment. It is:
1 54' 52'
Meaning if one is seeing the moon at 0 Aries, the other will sea it at +/- 1 54' 52 compared to the first.
Yes, the visual of an ecplise depends on the location of observer, as does combustion and planetary war. However, planets for purposes of sign position are calculated to the center of the earth as the ecpliptic is based on the center of earth. House positions in a bhava chalita chart, SHOULD BE, calculated based on observer, but they usually are not, they are in kala though. So if we use observer or center of earth depends on the plane of reference we are examining.
Thank @ernst
What about Rahu/Ketu, Are they considered planets and Calculated from center of the Earth ?
If yes, for calculating the Start and end of Solar Saros cycles when eclipses are partial and very mild and only observable at north or south pole we may not have enough information to find out if they are happening.
For example when Sun/Moon conjunction is about 17 degrees from Rahu/Ketu then the moons orbital plane inclination to ecliptic plane (measured by Latitude) and moons distance to earth may start playing a role for the eclipse to occur.
I'll give details on the eclipses given by Nasa and Eagle and the lark in an other thread.