Yes this is very true but there are many exceptions due to cancelation as well. And I'll present a list of the major ones.
Mind that the aspects in Vedic Astrology don't work as per Western Astrology, are considered only conjunctions (all planets in the same house) and oppositions. Saturn, Mars and Jupiter have extra special aspects.
When it's refered a trine in Vedic it's the 1st, 5th and 9th houses from the planet (house) in question.
So here it goes:
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Mangalik Dosha and Planets[/FONT]
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Mangalik Dosha is considered from the Ascendant as it signifies self, health, longevity, appearance, character, success and failure in life among other things.
Mangalik Dosha is considered from the Moon as it signifies Mind, emotions, infancy, personality, bovines, inclinations and emotions.
Mangalik Dosha is considered from Venus as it signifies marriage, sexual matters, love, beloved and bed pleasures. [/FONT]
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Cancellation Of Mangalik Dosha[/FONT]
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Following are the cases where Mars even if it is in 2nd, 12th, 4th, 7th or 8th house the manglik dosha gets cancelled: - [/FONT]
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1. When Mars is in its own sign (Aries, Scorpio), exalted (Capricorn) or in the houses owned by his friends (Sun, Jupiter, Moon) manglik dosha gets cancelled. [/FONT]
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2. If Mars is in the 2nd house but in Gemini, Virgo sign no dosha. [/FONT]
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3. If Mars is in 12th house but in Taurus, Libra no dosha. [/FONT]
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4. If Mars is in 7th house but in Cancer, Capricorn no dosha. [/FONT]
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5. If Mars is in 8th house but in Sagittarius, Pisces no dosha.[/FONT]
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6. For Cancer and Leo ascendant Mars is a yogakaraka wherever it may be no dosha at all. [/FONT]
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7. For Aquarius ascendant Mars in the 4th/8th house no dosha. [/FONT]
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8. If benefic Jupiter or Venus is in ascendant no dosha. [/FONT]
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9. If Mars is in conjunction or aspected by Jupiter or Moon no dosha.[/FONT]
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10. If Mars is in conjunction/aspected by Sun, Mercury, Saturn, Rahu no dosha. [/FONT]
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Thus we see that percentage of manglik cases decreases if we consider these factors. [/FONT]
[FONT=Arial, Helvetica, sans-serif]In consideration of marriage, various factors other than manglik dosha should be carefully be examined for a long and successful marriage.[/FONT]