Galatic Shift

IF you're a regular follower of astrology you should know that your horoscope could well be 2000 years out of date.

The star signs we are used to are based on constellations observed by the ancient Babylonians two millennia ago.

And according to some astronomers the astrological calendar has moved on – potentially by as much as a whole month.

The debate has created a storm on the internet after Minnesota Planetarium Society board member Professor Parke Kunkle pointed out the potential problem.

"When [astrologers] say that the sun is in Pisces, it's really not in Pisces," he said.

Professor Kunkle says the phenomenon is the result of something called “precession” caused by the wobble of the Earth affecting how we see the distinctive patterns in the night sky.

Sydney University’s Professor Tim Bedding said the Earth rotates on its axis but the axis does not point in the same direction all the time.

“What that means is that the time of year in which a sun passes through a constellation changes,” Professor Bedding said.

This action causes a change of one degree every 70 years in our viewpoint and while this is so small it is hardly noticeable after 2000 years it all starts to add up, he said.

We now see the star signs in different positions to when they were first observed.

Astrologers have hit back saying the debate is revived every few years to discredit their practice.

Ed Tamplin says the problem is one that actually confuses Babylonian “sun signs” with modern “star signs”.

“Sun signs do not correspond to constellations in the sky,” Mr Tamplin said.

“[They] share the same name as constellations only because the Sun, Moon and planets travel through a similar area of the sky.

“They actually define the equinoxes and the solstices.”

Mr Tamplin said while the constellations have moved from their original positions the pieces of sky (the signs) are still on the equinox and solstice positions.

“Ancient monuments like Newgrange, or Chichen Itza built by the astronomer priests still accurately measure the equinoxes and solstices to this very day,” he said.


That location in the sky has slowly drifted westward because of something called "precession" -- the earth continually wobbles (a scientific term for a slight motion) every 26,000 years. Since the constellations were first identified, they have shifted some 30 degrees. Translation: The signs have slipped about a month westward, relative to the stars.