Mercury Mahadasha, Moon Antardasha (Budh–Chandra)

The Moon antardasha is the fifth of the nine sub-periods inside the Mercury mahadasha. 17 × 10 ÷ 120 makes the Mercury–Moon sub-period 1 year 5 months on the classical year of twelve thirty-day months, which is how the texts state it, or 517 days on the solar year of 365.2425 days that the dasha calculator uses.

The Moon’s turn in the Mercury mahadasha comes only after Mercury, Ketu, Venus and the Sun have run, which takes 7 years 1 month. When the Mercury–Moon sub-period gives way to Mercury–Mars, 8 years 6 months of the Mercury mahadasha remains.

The Moon’s 10 years make every Moon antardasha 10/120 of the mahadasha containing it, so inside Mercury’s 17 years the Mercury–Moon sub-period is the sixth-longest of the nine.

The Nine Pratyantardashas of Mercury–Moon

A pratyantardasha of Mercury–Moon is 17 × 10 × its own lord’s years ÷ 14,400, and the nine run in cycle order starting from the Moon. Venus’s is the longest inside Mercury–Moon at 85 days and the Sun’s the shortest at 26 days, on the classical year and rounded to the day.

How Mercury and the Moon Stand to Each Other

On the natural friendship table, Mercury counts the Moon an enemy while the Moon counts Mercury a friend. The table is not symmetric, so the Mercury–Moon relationship has to be quoted in both directions, as it is here, rather than as one word.

Counted between the signs they own, Cancer is the 2nd from Mercury’s Gemini and Cancer is the 11th from Mercury’s Virgo. Whatever the ascendant, the houses Mercury rules and the houses the Moon rules sit at those same distances from each other in the chart, so the Mercury–Moon sub-period always joins lordships that far apart.

The Same Pair the Other Way Round: Moon–Mercury

17 × 10 equals 10 × 17, so the Mercury antardasha of the Moon mahadasha is exactly as long as Mercury–Moon: 1 year 5 months. Nothing else about Moon–Mercury matches. It is the sixth sub-period of the Moon’s 10 years rather than the fifth of Mercury’s 17; it opens after 5 years 10 months of the Moon mahadasha, against 7 years 1 month here; and its pratyantars start from Mercury instead of the Moon.

What the Texts Assign to Mercury and the Moon

The karaka list the tables give Mercury, the mahadasha lord, is speech, writing, trade, accounts, mathematics, maternal uncles and students; for the Moon, the lord of the Mercury–Moon sub-period, it is mother, the mind (manas), water, milk, the public, comfort and the home. Parashari practice reads the sub-period through the houses each of the two owns and occupies in the birth chart, and through where the Moon stands counted from Mercury there. None of that is a forecast, and this page makes none: without a chart, Mercury–Moon is a length and a position, and the 1 year 5 months above is the whole of what can be said about it in general.

A birth with the Moon in Ashlesha, Jyeshtha or Revati opens life inside the Mercury mahadasha itself, part-way through, and whether the Mercury–Moon sub-period is still ahead depends on how far the Moon had gone into the nakshatra. For a birth in Rohini, Hasta or Shravana, the Moon mahadasha comes first, and the Mercury mahadasha is the sixth in that sequence.

The Other Sub-Periods of the Mercury Mahadasha

The full table for the Mercury mahadasha, with where each sub-period opens and closes, is on the Mercury mahadasha page. How the Mercury mahadasha is read as a whole is in our Mercury mahadasha article, and the system itself in Vimshottari dasha explained. This page in Hindi: बुध महादशा में चन्द्र अंतर्दशा.