The Nine Grahas (Planets)

The basic idea

The word graha comes from a root meaning “to seize” or “to grasp”. Grahas are the bodies that move through the zodiac and, in Jyotisha, “grasp” the signs and stars they pass through. In the chart, the grahas are the main actors. The rashis (signs) are the stage, and the bhavas (houses, a later topic) are the areas of life.

There are nine grahas:

Seven are visible bodies: Surya (Sun), Chandra (Moon), Mangala (Mars), Budha (Mercury), Guru (Jupiter), Shukra (Venus) and Shani (Saturn).
Two are shadow points (chhaya grahas): Rahu and Ketu. They are not bodies but the two points where the Moon’s path crosses the Sun’s path. They sit exactly opposite each other, 180° apart.

Calling the Sun and Moon “planets” is a Jyotisha convention. Here “graha” simply means “something that moves through the zodiac and matters in the chart.”

See how they move

Everything is seen from the Earth at the centre. Each graha travels around the twelve signs at its own pace. Click one to read about it, and use the speed slider to slow down or speed up time.

Things worth noticing as it plays:

The numbers 1 to 12 on the outer ring are the signs, starting with Mesha at the top.
The Moon is by far the fastest, going round in about 27 days. Saturn is the slowest of the seven, taking close to 30 years.
Mercury and Venus never wander far from the Sun, which is why they seem to accompany it.
Rahu and Ketu always move backwards through the signs, taking about 18.6 years for the full round.

The nine at a glance

Graha	English	Weekday	Usual nature	Own sign(s)	Exalted in	Debilitated in
Surya	Sun	Sunday	Mildly malefic	Simha	Mesha (10°)	Tula (10°)
Chandra	Moon	Monday	Benefic when waxing	Karka	Vrishabha (3°)	Vrishchika (3°)
Mangala	Mars	Tuesday	Malefic	Mesha, Vrishchika	Makara (28°)	Karka (28°)
Budha	Mercury	Wednesday	Depends on company	Mithuna, Kanya	Kanya (15°)	Meena (15°)
Guru	Jupiter	Thursday	Benefic	Dhanu, Meena	Karka (5°)	Makara (5°)
Shukra	Venus	Friday	Benefic	Vrishabha, Tula	Meena (27°)	Kanya (27°)
Shani	Saturn	Saturday	Malefic	Makara, Kumbha	Tula (20°)	Mesha (20°)
Rahu	Moon’s north node	none	Malefic	none in the basic scheme	teachers differ	teachers differ
Ketu	Moon’s south node	none	Malefic	none in the basic scheme	teachers differ	teachers differ

A few notes on reading this table:

Own sign is a sign a graha rules, where it is traditionally comfortable. You saw the rulers in the table on the rashis page.
Exalted is the sign (and exact degree) where a graha is considered strongest. Debilitated is the opposite sign, at the same degree, where it is considered weakest.
Benefic and malefic here is the simple natural classification. Whether a graha actually helps or troubles a particular chart depends on much more, such as the houses it rules and where it sits. I am leaving that for later.
For Rahu and Ketu, I have seen different traditions give different signs, so I am not copying any of them until I understand the reasons.

What each graha is traditionally linked with

These themes are called karakatva, the things a graha “signifies”. I am noting only the commonly listed basics.

Graha	Commonly linked with
Surya	Soul, vitality, father, authority
Chandra	Mind, emotions, mother
Mangala	Energy, courage, siblings
Budha	Intellect, speech, trade
Guru	Wisdom, teachers, children, fortune
Shukra	Relationships, arts, comfort
Shani	Discipline, hardship, longevity, work
Rahu	Obsession, the foreign, illusion
Ketu	Detachment, liberation, past habits

Questions I still have

How exactly are a graha’s friends, enemies and neutrals decided, and how does that change its results?
What does it mean for a graha to be retrograde (vakri), and why do Rahu and Ketu always appear retrograde?
Why do traditions disagree about the exaltation signs of Rahu and Ketu?
Which houses do the grahas rule for each ascendant?

(I will come back to these as I study further.)