Yoga — Sun + Moon Combined

We have looked at three of the five limbs so far. Tithi tells us where the Moon is relative to the Sun, by subtracting their longitudes. Vara tells us the weekday. Nakshatra tells us where the Moon is against the background stars.

We come now to the fourth limb — the yoga (योग). The Sanskrit word yoga literally means “union” or “joining,” from the root yuj, “to yoke.” In this context, the union being joined is between Sun and Moon — but unlike tithi, which considers their separation, yoga considers their combined longitude.

A note before we begin. The word “yoga” in Sanskrit has many other technical meanings — the spiritual discipline of yoga, planetary conjunction yogas in a kundli (gajakesari yoga, dhana yoga, etc.), and special panchang combinations like Amrit Siddhi yoga and Tripushkar yoga. The nityayoga of the panchang is yet another usage — the one we treat in this chapter. Each of these uses the same Sanskrit word for a different specific concept. Context disambiguates. We will explicitly call this one nitya yoga (नित्य योग)— “daily yoga” — when there is risk of confusion.

The mathematics of yoga

There are 27 yogas. The full ecliptic of 360° is divided into 27 equal segments, each of 13°20′ — exactly the same span as a nakshatra. But the quantity being divided is different.

Yoga number = floor(((λ_Moon + λ_Sun) mod 360°) ÷ 13°20′) + 1

Why divide the sum of longitudes? The astronomical motivation is subtle. The sum (λ_Moon + λ_Sun) advances at the combined rate of the Moon and the Sun together — about 13.18° per day (Moon’s daily motion) + 0.99° per day (Sun’s daily motion) ≈ 14.17° per day. So the yoga changes about every 13.20° ÷ 14.17° ≈ 22.4 hours — a bit faster than a tithi, which advances at 12.18° per day (the differential rate) and so changes every ~23.6 hours.

Yoga is thus a refinement that captures a different aspect of the Sun-Moon configuration than tithi does. Where tithi encodes the phase of the Moon (waxing or waning, how far separated), yoga encodes a different angular relationship — one that has historically been used for fine-grained muhurta selection.

Why 27 again? — the parallel to nakshatra

It is no accident that the number 27 appears for both the nakshatra (which divides the Moon’s longitude by 13°20′) and the yoga (which divides the Sun-plus-Moon longitude by 13°20′). The framework was reused for symmetry: 27 nakshatras of 13°20′ on the ecliptic, 27 yogas of 13°20′ on the combined-longitude scale.

Both yogas and nakshatras share names with ancient Vedic roots, though the lists are completely different. The 27 yogas have names like Vishkambha (obstruction), Priti (affection), Ayushman (long-lived) — these names directly encode the yoga’s nature, unlike nakshatra names which are mostly descriptive of the constellation.

The 27 yogas with their qualities

Below is the master table of all 27 yogas with their traditional natures. Out of 27, fourteen are explicitly auspicious, eight are explicitly inauspicious, and a few are mixed or context-dependent.

The seven inauspicious yogas to know

For practical panchang reading, the most important thing is to recognise the inauspicious yogas, which are flagged for avoidance during important new beginnings. These are traditionally listed as:

1. Vishkambha (1) (विष्कम्भ)— “obstruction.” Only the first 5 ghatis (~2 hours) of this yoga are considered inauspicious; the rest is normal.
2. Atiganda (6) (अतिगण्ड)— “great obstacle.” First 6 ghatis flagged.
3. Shula (9) (शूल)— “spear, piercing pain.” First 5 ghatis flagged.
4. Ganda (10) (गण्ड)— “knot, obstruction.” First 6 ghatis flagged.
5. Vyaghata (13) (व्याघात)— “striking.” First 9 ghatis flagged.
6. Vajra (15) (वज्र)— “thunderbolt.” First 9 ghatis flagged. Mixed nature; powerful for strong actions, harsh for delicate ones.
7. Vyatipata (17) (व्यतीपात)— “sudden fall.” The entire yoga is considered inauspicious and is one of the most strongly flagged panchang elements. Auspicious work is traditionally avoided throughout this yoga.
8. Parigha (19) (परिघ)— “iron bar, obstruction.” First 5 ghatis flagged.
9. Vaidhriti (27) (वैधृति)— “disconnection.” The entire yoga is inauspicious — the second of the two strongly flagged full-yoga inauspicious periods alongside Vyatipata.

Of these, Vyatipata and Vaidhriti are the two flagged through their entire duration; the others have only an initial unfavourable window of a few ghatis. The panchang on this site flags these when active.

The auspicious yogas of greatest weight

Three yogas are noted in classical texts as particularly favourable for new beginnings, and worth specifically choosing for muhurta:

• Siddhi (16) (सिद्धि)— “accomplishment.” Strongly favours endeavours that require completion of a difficult task.
• Shubha (23) (शुभ)— “auspicious.” A general-purpose favourable yoga.
• Brahma (25) (ब्रह्म) — favours scholarly, philosophical, ritual, and spiritual undertakings.

When Brahma yoga falls on a Thursday (Guru-vara) and the nakshatra is Pushya, the combination is one of the highest muhurtas in the entire calendar — a confluence of three favourable currents.

Yoga in muhurta selection

In strict muhurta practice, the panchang is consulted to find a moment when several factors line up favourably:

• The tithi is auspicious for the activity.
• The vara’s graha is favourable.
• The nakshatra is favourable for the activity type.
• The yoga is auspicious or at least not actively inauspicious.
• The karana is favourable.

The yoga is essentially a fifth filter, used to rule out moments when an otherwise fine confluence happens to fall within Vyatipata or Vaidhriti, or in the unfavourable opening ghatis of one of the other inauspicious yogas. Many marriage and major-ceremony muhurtas are explicitly checked against the yoga in addition to the other limbs.

Reading yoga in your panchang

On the daily panchang of this site, the yoga line shows the current yoga at sunrise and the time at which it ends. After that time, the next yoga in sequence begins.

If today’s yoga is Vyatipata or Vaidhriti, the entire day is flagged. If it is one of the other inauspicious yogas, the panchang notes the unfavourable opening ghati window. If today’s yoga is Siddhi, Shubha, or Brahma, the day is highlighted as particularly favourable.

What you should be able to do now

After this chapter, you should be able to:

• State the formula for nitya yoga (sum of Sun and Moon longitudes ÷ 13°20′).
• Distinguish nitya yoga from the other meanings of “yoga” in Sanskrit astrology.
• Name the seven traditional inauspicious yogas.
• Identify Vyatipata and Vaidhriti as the two yogas inauspicious throughout their entire duration.
• Name the three highly auspicious yogas (Siddhi, Shubha, Brahma).
• Read the yoga line of a daily panchang.

In the next chapter we look at the last of the five limbs — karana — which is simply half a tithi, but with a structure that is unexpectedly rich.