[Advaita-l] Velocity of the planets as told by Aryabhata

[Raghav Kumar Dwivedula]

On Sat, 19 Sep, 2020, 4:08 PM P R via Advaita-l, <
advaita-l at lists.advaita-vedanta.org> wrote:

> *Velocity of the planets in a yuga from Aryabhatiya*
>
>
>
> The velocity of the planets, that is the number of revolutions in a yuga (
> 432 * 10^ 4) are mentioned in the aryabhatiya gitika shloka 3 and 4
>
> The planets are arranged in the increasing order if their velocity, along
> with explanations
>
> The rule *अङ्कानाम् वामतोगतिः* is used invariably here
>
>
> 1.  Saturn ( Shani) दुङ्विध्व
>
> ढ् (उ) + ङ् (इ) + व् (इ) + घ् (अ) +व् (अ)
>
> 14( 10^4) + 5 (10^2) + 6(10^3) +4(1) +6(10)
>
> = 1,46,564


Namaste Sri PR ji
I have not seen the Aryabhatiya.

Thanks for sharing your interesting explanation of the chaturyuga cycle
measured in terms of number of planetary orbits.

If we wish to check with modern figures, I  observed that 146564*29 yrs
(orbital period of Saturn from modern observation) gives 4,250,356 which is
a close fit for one chaturyuga cycle. That is neat. This tally with modern
observation is a testimony to a fairly reasonable precision in ancient
Indian observational astronomy.

>
> 2. Guru ( Jupiter) ख्इच्युभ
> ख(इ) + र् (इ) + च् (उ) + य्(उ) + भ् (अ)
>
> 2(10^2)+ 4(10^3) + 6 (10^4) + 3(10^ 5) +24(1)
>
> = 3,64, 224
>

This gives us 4,297,843 yrs agsin a decent fit for a 11.9 yr orbit of
Jupiter.


> 3 Mangala ( Mars) भद्लिझुनुखृ
>
> भ(उ) +द्(इ) +ल् (इ) + झ् (उ) + न् (उ) + ख(ऋ)
>
> 24(10^0) + 18(10^2) + 5(10^3)+ 9(10^4)+20(10^4) +2(10^6)
> = 22,96,824
>

Multiplying by 687 days martian orbit/365 we get 4323063 years which is
also close to the chaturyoga time.


> 4. Ravi (sun) ख्युघृ
>
>  ख् (उ) +य् (उ)+घ्(ऋ)
> 2(10^4) + 3(10^3)+ 4(10^6)
>
> = 4320000
>
> 5. Soma (moon) चयगियिङुशुछृलृ
>
> च्(अ) +य्(अ) +ग्(इ) +य्(इ) +ङ्(उ) + श्(उ) + छ् (ऋ) +ल् (ऋ)
>
> 6(1)+3(10)+3(10^2)+3(10^3)+5(10^4)+7(10^5)+7(10^6)+5(10^7).


This gives 5,77,53,336 lunar revolutions times 27.3 days per lunar orbit
gives 43,19,633 years - again a good match.

*अङ्कानाम्
> वामतोगतिः* rule is used here
>
> Just a small observation and calculation done while reading the aryabhatiya
> with the commentary bhaTTa deepikA by paramadievara
>

I wish to ask you a question.
Do you happen to know if any of the ancient astronomical treatises mention
a heliocentric model?

We did know for example, that the lunar nodes created by the inclination of
the lunar orbit with the ecliptic plane gives rise to the Rahu and Ketu
nodal points which themselves move due to precession of the lunar orbital
plane w.r.t. the ecliptic plane . Thus we were able to accurately predict
solar and lunar eclipses. Many modern Indians don't know that the ancient
astronomers of India clearly knew the cause of eclipses as the shadow of
the moon and Sun. The popular folktale of Rahu and ketu being monsters
swallowing the sun and moon was treated as just a folktale. At least by
Aryabhata and Varahamihira's time in c.500 AD, the cause and occurrences of
eclipses was clearly understood.

My request is about a different issue -  if you could share with us
whether, a heliocentric theory was in vogue in any of these ancient texts
like AryabhaTIya or brihatsamhitA etc . ( I have only heard of these texts
, never studied them.)

I do appreciate that a driggaNita based observational astronomical model is
sufficient and even quite convenient for say, astrological uses. But that
(the chart looks geocentric) need not imply that they (Aryabhata etc)
actually believed in a geocentric theory in recording their ephemeris - it
may have been only for practical convenience.

So, is there any mention of heliocentrism anywhere?

Thank you
Raghav




_______________________________________________
> Archives: https://lists.advaita-vedanta.org/archives/advaita-l/
> http://blog.gmane.org/gmane.culture.religion.advaita
>
> To unsubscribe or change your options:
> https://lists.advaita-vedanta.org/cgi-bin/listinfo/advaita-l
>
> For assistance, contact:
> listmaster at advaita-vedanta.org
>