So, today we got up early enough to try catch a glimpse of the Venus transiting over the Sun. Venus planet was to pass over the disc of the Sun as viewed from earth. Most of the other times of such transits, Sun appears to pass over the Venus and not Venus passing over the Sun. The orbital speed of earth and Venus are so close that even though Sun and Venus come in close angles with each other as seen from earth multiple times a year, the event of Venus itself coming in between the Sun and the Earth happens only twice in around 105 years or more!!
Cloudy day as it was, the monsoon had hit just a day or two ago. Couldn't watch it because of the clouds even after waiting for a long time. Unfortunately, the June 2012 transit was not visible to us at Bangalore. The last time ,it had happened in June 2004; 8 yrs back. I don't know how we missed the 2004 event, but it was most probably the ignorance about the event itself (may be we were reading The Da Vinci Code, that was just released :-).)
This astronomical event occurs always in pairs - each event pair separated by 8 yrs. Before this 2004-2012 pair, it had occurred in Dec 1874 - Dec 1882. Next one would be Dec 2117 and Dec 2125.
That means, in my genealogy, my great grandfather (1888 born), my grandfather (1919 born), my father ('50 born), myself ('80 make-n-model) and probably my son (2010 born; unless my blessings come true and he lives for more than ~108 years) have missed witnessing the phenomenon in the sky.
Anyways, to the million dollar question - what gives? what's so different about it compared to any other day?
Like Sherlock Holmes had ignored the Copernicus theory of Solar System without affecting him or his job, it is nothing that impacts our day to day lives. It is just a rare, predictable event of astronomical significance which astronomers wait for 100's of years, to witness and make astronomical observations in the sky optionally using telescopes and other devices to record the exact start and end times of the events as seen from two different places on earth (so that they can use the parallax between the two places) to be able to calculate the distance between Sun and Earth and arrive at a more exact figure of 1 Astronomical Unit. This is one such event which doesn't repeat very often and that rareness in itself makes it worthwhile to watch.
Okay, done is done, we missed it. So did many. :)
Lets just settle for and see the Mercury transiting over Sun. Good news, that's more often. Happens nearly 15 times in 100 years. Next one sometime in 2016.
No, you can't see Mars, Jupiter, Saturn transiting over Sun's disc. They are outside earth's orbit and hence always (I mean always), Sun appears in between earth and those planets whenever they are angularly close to Sun. Example, when Jupiter is angularly close to Sun, which happens once every year, Sun is 'apparently' actually in between Earth and Jupiter. So forget about seeing Mars, Jupiter, Saturn etc transiting over the Sun's Disc, unless you are standing on the planet outside the solar orbit of the planet you want to watch - that is, standing on Mars, you can see Earth (or Mercury/Venus) transiting over Sun's disc, standing on Jupiter, you can see Mars (or Earth/Venus/Mercury) transiting over Sun's disc and standing over Saturn, see Jupiter (or Mars/Earth/Venus/Mercury) transiting over Sun's disc, etc.
But, as long as you are standing on earth, you have only two options - Venus and Mercury. AND... Today, you just missed the possibility of seeing Venus transit over Sun's disc! Congrats. Now you can never watch venus transit over the Sun's disc ever in your life and probably your children will miss it as well.
Another question. Did vedic astrologers know about this phenomenon? How do they use this? If you search the internet, they say the same old stuff - our ancient civilization did not 'probably' know about this. But, like always, I beg to differ. :-)
In Surya Siddhanta and Brihat Jaataka, we have the mention of 'adhikramana' to be considered as a negating factor for 'dagdha' and is applicable only to Shukra (Venus) and Budha (Mercury). Sounds familiar? They are talking about this very thing.
Dagdha is the 'apparent' closeness of Sun with ANY of the planets, Moon (yes, I call it planet for now), Mercury, Venus, Mars, Jupiter, Saturn. When Moon is +/- 12 deg from Sun, when Mercury is +/- 14 deg from Sun, when Venus is +/- 10 deg from Sun, when Mars is +/- 17 deg from Sun, when Jupiter is +/- 11 deg from Sun, when Saturn is +/- 16 deg from Sun, that planet is considered as Dagdha or combust with Sun. During such closeness, the effect of the planet in the horoscope is deemed to be weakened. Astrologically, it is taken as default rule that when these 'planets' are in respective close proximity with the Sun, Sun's effect supersedes their impact. I will not talk about what impact each planet can give, but the concept remains same. The only exception to this dagdha graha is for Mercury and Venus during the time of 'adhikramana'; obviously because, as viewed from earth, Mercury and Venus, even during the close proximity will continue to be visible to earth.
Now, our ancient documents record this 'adhikramana' in Ramayan as well. Probably in Mahabharat too, knowing the abundance of the astronomical events recordings throughout that scripture. So, we Indians, knew about dagdha and 'adhikramana as applied to just two planets' which means we knew the Solar System model as taught today (otherwise, there is no reason for excluding just Venus and Mercury for the concept of Dagdha at the selected 'adhikramana' times alone and the methodology that is given in panchanga calculations to arrive at the adhikramana timeframes and ignore Mercury and Venus 'dagdha' concept only during those times). So, while writing a Jaataka and pronouncing the effects and results, by default, dagdha is considered and results of the horoscope predicted likewise unless it is a adhikramana time where, the effect of the dagdha planet is taken as if it is not combust, and results calculated as-is instead of deeming it weakened.
It is pretty straight forward implication that the solar system as is knowledge (yathartha gnaana) persisted earlier than the current world thinks of.