Rules: Aries (and classically Scorpio) / 1st house (and classically 8th house)
Natal significance: Mars shows your drive, how and where you exert your energy, including both aggressiveness and sexual drive. Where you find Mars is where you are likely to be energetic, assertive, impulsive and even -- depending on aspects -- cruel or violent. Unsurprisingly, it also represents the "masculine" principle -- in a man's chart, how he sees himself a man; in a woman's chart, what she seeks from men or maleness and her inner "masculinity."
Transiting significance: Where Mars moves through your chart is where you are likely to concentrate your drive and energy for a period of roughly two months. Aspects between the Moon and Mars can lead to tension and anger; between Venus and Mars, to sexual sparks. Extremely difficult Mars aspects can contribute to cruel or violent tendencies.
