Question

Arrange the following values of 'Laṅkōdaya' (rising times of signs at the Equator) in their correct order for the signs starting from Aries (Mēṣa) through Virgo (Kanyā):
A. 323
B. 299
C. 278
D. 323
E. 299

• A. C, B, A, D, E
• B. B, D, C, A, E
• C. E, C, D, B, A
• D. A, E, C, D, B

Hint:

To remember Laṅkōdaya: Think 278, 299, 323. The signs near the Equinoxes (Aries/Libra) rise fastest. The signs near the Solstices (Gemini/Cancer/Sagittarius/Capricorn) take the longest to rise.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
In Indian Mathematical Astronomy (Siddhānta Jyōtiṣa), 'Udayamāna' refers to the time taken by each zodiac sign (Rāśi) to rise completely above the eastern horizon. Because the ecliptic is tilted relative to the celestial equator (obliquity), and because the earth is a sphere, different signs take different amounts of time to rise. 'Laṅkōdaya' specifically refers to these rising times as calculated for a place on the Earth's equator (symbolized by the ancient city of Laṅkā). These values are measured in 'Asu' (a unit of time where 6 Asu = 1 Vināḍī, and 360 Asu = 1 Ghaṭī).

Step 2: Detailed Explanation:
The calculation of Laṅkōdaya is the foundation for finding the rising times at any other latitude (Svadeśōdaya). Due to the symmetry of the celestial sphere, the rising times follow a specific pattern of expansion and contraction.

1. The First Triad (Aries to Gemini): As we move from the vernal equinox toward the summer solstice, the rising times increase.
- Mēṣa (Aries): 278 Asus.
- Vṛṣa (Taurus): 299 Asus.
- Mithuna (Gemini): 323 Asus.

2. The Second Triad (Cancer to Virgo): The values then mirror themselves in reverse order as the sun moves back toward the autumnal equinox.
- Karka (Cancer): 323 Asus.
- Siṃha (Leo): 299 Asus.
- Kanyā (Virgo): 278 Asus.

Mapping these to the provided letters:
- Aries is C (278).
- Taurus is B (299).
- Gemini is A (323).
- Cancer is D (323).
- Leo is E (299).
(Virgo would be 278).

The sequence for the first five signs provided in the options is therefore C, B, A, D, E. These values are derived using spherical trigonometry, specifically involving the 'Cara' (ascensional difference) and the right ascension (Vishuval-lagnas) of the signs. At the equator, the 'Cara' is zero, so the rising times are equal to the differences in right ascension of the endpoints of the signs. These standardized values (278, 299, 323) are used by almost all traditional Pañcāṅga makers to calculate the local Lagna (Ascendant) by applying a latitude correction called 'Carakhaṇḍa'.

Step 3: Final Answer:
The correct chronological order of the values for the signs Aries to Leo is C, B, A, D, E.