Several cultures have helped develop the art of astrology: Babylonia, China, Greece, and India, plus the medieval Islamic world. While their existences collectively span centuries of human history, they all have one thing in common – they’re located north of the equator. Since our modern astrological practices have roots in these cultures, it’s also more focused on the Northern Hemisphere. But how does astrology work for those living south of the equator? The answer to this question may surprise you.
The Zodiac on the Ecliptic
When we think about the zodiac, we may picture the band of 12 constellations circling Earth. At least that’s how they appear to us. EarthSky contributor Christopher Crocket tells us that the ecliptic is the apparent path of the sun across our sky. It also defines which part of the sky we see at any given time. From our perspective, the constellations look like a giant band that revolves around our planet. Just like Earth’s rotation and orbit make it look like the Sun is moving, the same effect happens with the constellations.
Tropical Astrology and Axial Tilt
Have you had your birth chart done? If so, it probably used tropical astrology for sign, house, and planet placements. That doesn’t mean your astrologer composed it while drinking jaguar coladas on a sandy Costa Rican beach. The word “tropical” refers to how astrologers define the year – in this case, the 12-sign zodiac starts at zero degrees Aries on the date of the spring equinox. The tropical zodiac doesn’t really change, regardless of where the constellation Aries actually appears in our night skies. And there’s where differences between the Northern and Southern Hemispheres first show up.
Mystic Medusa Astrology explains that we tend to think of the tropical zodiac corresponding with Northern Hemisphere seasons. Aries starts spring, Cancer begins the summer, Libra kicks off the fall, and Capricorn marks the beginning of winter. Yet it works differently south of the equator. In the Southern Hemisphere, the summer and winter solstices are on December 21 and June 21 respectively.
Why do these differences exist? The answer lies in our planet’s axial tilt, currently at 23.4 degrees. Encyclopedia Britannica mentions that this tilt plus our Earth’s solar orbit affect which of its poles is closer to the sun. They also shift how the sun’s rays strike Earth’s surface – directly overhead at the Tropic of Cancer on June 21 and the Tropic of Capricorn on December 21.
Oh, Mirror in the Sky
Northern Hemisphere observers see the Sun rising the east and setting in the west, moving from left to right in the southern sky. In the Southern Hemisphere, the sun moves from right to left across the northern sky. These movements are clockwise and counterclockwise respectively. So what does this mean for our tropical zodiac? Right now, most astrologers don’t think that people in the Southern Hemisphere are born under opposite signs than in the North. So a Leo is still pretty much a Leo, whether that person was born in Chicago, Illinois, or Sydney, Australia.
Meanwhile, Mystic Medusa points out that some differences will exist between their charts. Their lunar nodes are reversed – the Chicago individual’s lunar North Node would be the South Node for the person in Sydney. Southern Hemisphere birth charts should also show the horoscope houses in counterclockwise order. And thanks to the Sun’s right-to-left movement, the Ascendant should appear on the right side of the chart instead of the left.
One Planet, Many Realities
Astrology involves some science, but it’s also a matter of perspective. We have billions of people living on a spherical planet, seeing only part of the sky at any given time. Holding space for those differences is key to a broader understanding of this fascinating art.