Summary: Covers a key component of chart interpretation – assessing the ‘strength’ or ‘power’ of a planet from its sign placement in a birth-chart. Also explains house rulership (ownership) and ‘friends and enemies’ concepts
In Jyotish, a key component of chart interpretation lies in assessing the ‘strength’ or ‘power’ of a planet.
A planet that is classified as ‘strong’ brings many benefits and signifies positive returning karmas. In general, ‘strong’ equates with ‘good’!
There are two ways in which ‘strong’ equals ‘good’
Firstly some of the benefits will be in the life areas indicated by the natural associations or indications of that planet.
For example our health, power, self-esteem, relationship with father are natural associations or indicators of the Sun. Whereas our mind, emotions, memory are associated with the Moon. (See the aricle on ‘natural indications’ of planets for details)
Secondly, a strong planet brings benefits to the Houses associated with the signs it ‘owns’ or ‘rules’ [1].
Assessing Planetary Strength from Sign Placement
Although there are numerous ways of assessing a planet’s strength, a fundamental indication of strength is to assign a particular state depending on the sign of the zodiac in which the planet is located. Sometimes even the sector of the sign (say the first 10 deg.) makes a difference to the level of ‘strength’.
In Vedic astrology there are certain signs in which a planet is said to be ‘strong’ or ‘powerful’ and so can deliver benefits, whereas in other signs it is said to be ‘weakened’ so we might expect more challenges, difficulties or negative returning karmas in the life areas associated with it. Therefore the strength of a planet depends on its relationship with the sign of the zodiac in which it is placed (or passing through).
When beginning astrology, we can make quite a good initial observation of a birth-chart simply by first looking to see if each of the nine planets is in one of the four key categories of strength.
These are called, ‘Exalted’, ‘Moolatrikona’, ‘Own House’, ‘Debilitated’ (weakened or ‘fallen’).
The state of ‘Moolatrikona’ (no direct English equivalent word) brings benefits somewhere between the best state ‘exalted’ and the good state ‘own house’.
The sign where a planet is weakest (Debilitated) is exactly 180° opposite its position of maximum strength (Exalted).
Suppose we take a naturally positive planet such as Venus. If Venus is in its sign of Exaltation (Pisces), it will bring tremendous benefits (both to its natural indicators, and also to the two houses associated with the signs it rules – Libra and Taurus; the house numbers linked to these signs will of course depend on the particular ascendant in the birth-chart). However, if Venus is located in its sign of Debilitation (Virgo), it will bring no benefits whatsoever.
Therefore the same planet can act in very different ways according to its sign placement!
Planetary Strengths or Powers by Sign Placement
Sun
Exalted sign: Aries (maximum strength at Aries 10°)
Moolatrikona sign: Leo 0° to 20°
Own sign: Leo 20° to 30°
Debilitated sign: Libra (maximum weakness Libra 10°)
Moon
Exalted sign: Taurus 0° to 3°
Moolatrikona sign: Taurus 3° to 30°
Own sign: Cancer
Debilitated sign: Scorpio (maximum weakness at Scorpio 3°)
Mars
Exalted sign: Capricorn (maximum strength at Capricorn 28°)
Moolatrikona sign: Aries 0° to 12°
Own signs: Aries 12° to 30° and Scorpio
Debilitated sign: Cancer (maximum weakness at Cancer 28°)
Mercury
Exalted sign: Virgo 0° to 15° (maximum strength at Virgo 15°)
Moolatrikona sign: Virgo 16° to 20°
Own signs: Virgo 20° to 30° and Gemini
Debilitated sign: Pisces (maximum weakness at Pisces 15°)
Jupiter
Exalted sign: Cancer (maximum strength at Cancer 5°)
Moolatrikona sign: Sagittarius 0° to 10°
Own signs: Sagittarius 10° to 30° and Pisces
Debilitated sign: Capricorn (maximum weakness at Capricorn 5°)
Venus
Exalted sign: Pisces (maximum strength at Pisces 27°)
Moolatrikona sign: Libra 0° to 15° and Taurus
Own signs: Taurus 15° to 30° and Libra
Debilitated sign: Virgo (maximum weakness at Virgo 27°)
Saturn
Exalted sign: Libra (maximum strength at Libra 20°)
Moolatrikona sign: Aquarius 0° to 15°
Own signs: Aquarius 15° to 30° and Capricorn
Debilitated sign: Aries (maximum weakness at Aries 20°)
Rahu
There are considerable differences of opinion in the ancient texts about the signs where Rahu and Ketu are strong or weak. So the following are quoted using the best sources I have available.
Exalted sign: Taurus
Debilitated sign: Scorpio
Ketu
Exalted sign: Scorpio
Debilitated sign: Taurus
House ‘Ownership’ or ‘Rulership’ Principles
A ‘strong’ planet also brings benefits to the signs associated with that particular planet. By ‘association’ we mean sign(s) the planet is said to ‘own or rule’. The Vedic seers allocated each of the signs to a particular planet:

For example, the Sun is said to be the ‘owner or ruler’ of the sign of Leo (sidereal). A strong Sun therefore brings benefits to the house number in the birth chart that corresponds with the sign of Leo. It brings benefits to all life areas that specific house indicates. The house number (1 to 12) will of course depend of on a person’s ascendant. If a person had a Cancer ascendant, then Leo becomes the second house (counting clockwise). So a strong Sun would bring benefits associated with the second house e.g. wealth
Note that in Jyotish signs and houses correspond exactly – unlike in some western astrological systems.
Suppose a person had an ascendant in Aries – this sign then becomes the first house and the sign of Leo (counting clockwise from Aries – yes clockwise, unlike in the Western system) would be the 5th house. So, if the Sun was ‘strong’ (by sign placement – see below) the affairs indicated by the 5th house e.g. children, intelligence and education, would also be supported in a positive way. This is in addition to the natural indications of the Sun (health, power, etc.) being positively supported.
Additional Measures of Strength – ‘Friends’ and ‘Enemies’
Professional astrologers add a number of other states lying between the ‘own house’ and ‘debilitated’ states. These are a bit more complicated for beginners but they ‘fine tune’ the chart interpretation.
These five intermediate states are named as follows: ‘Great Friends’, ‘Friends’, ‘Neutral’, ‘Enemies’, ‘Great Enemies’.
A planet positioned in a sign owned by a ‘Great Friend’ does well, but one in a sign owned by an ‘Enemy’ is weakened. Of course, planets don’t actually have ‘friends’ or ‘enemies’. It is just a convenient way of saying that a planet such as Venus is less ‘happy’ (so will bring less benefits) when positioned in the sign of an ‘enemy’ such as the Sun. Good Vedic astrological software will show these states for each planet in a birth-chart.
The above, together with ‘Exalted, ‘Own House’ and ‘Debilitated (‘Fallen’) are the primary planetary strengths or ‘Avasthas’.
For a proper chart interpretation we should take these nine detailed levels into account, but when we are starting to look at charts for the first time we can just use the four key states: Exalted, Own, Moolatrikona and Debilitated. They give a surprisingly accurate picture of an individual’s returning karmas! If you are in any doubts about the validity of Jyotish check these strength indicators out in the charts of your friends and family.
The sage Parashara quantifies the benefits a planet in each state can bring:
Exalted 100%, Moolatrikona 75%, Own House 50%, Friendly sign 25%, Neutral sign 12%, and Fallen/Enemies sign 0%.
This gives us a general idea of how the state of a planet affects the good it can do. We don’t have to take the above figures too literally – but they give a good illustration of the concepts.
Other Factors Which Influence Planetary Strength
There are also other factors which influence strength. For example, if the planet appears to be moving backwards against the background of the fixed stars (i.e. ‘retrograde’), if it is very close to the Sun (i.e. ‘combust’), or within about 1 degree of another planet (i.e. involved in ‘planetary war’). A planet’s position in the divisional charts (e.g. the ninth division or ‘marriage’ chart) also affects its overall power and ability to do good.
There are also other ‘Avasthas’ or ‘states’ which modify planetary strengths. Wikipedia comments: ‘Avasthas are basically secondary sources of strength which temper interpretations rather than reverse them’. If Wiki is talking about these other Avasthas (such as ‘youth’, etc.) and not the primary ones (Exalted, Own, etc.) then I agree. For those wishing to research this further, WikiZero has an interesting article on Avasthas.
These other influences on planetary strength will be covered in further articles.
Additional Resources on Jyotish
Introduction to Jyotish. A range of articles for people entirely new to Vedic Astrology. Including: Introduction, FAQs, Origins and Karmic Implications.
Key Concepts in Jyotish. Articles covering the Sidereal Zodiac, Planetary Forces, Forecasting Analogies and ‘Planetary Antidotes’.
For Western Astrologers. Articles examining major differences between the two systems and the paradigm shift needed by Western Astrologers wanting to understand the subject.
Learn Jyotish. An extensive collection of articles covering key facts, concepts and methods. Aimed at ‘foundation level’ students. Includes essential information needed before beginning chart interpretations. Covering: Chart Formats, Planets, Houses, Mahadasha Periods, Transits, Aspects, Birth-time Errors, Natural and Functional Benefics / Malefics, Chart Interpretation Basics, etc.