365DaysDate: February 27, 2009


Title: The Dawning of the Age of Aquarius. Or is it? (Astrology Part 1)

Podcaster: Patrick McQuillan

Organization: Incorporated Research Institutions for Seismology (IRIS)

Description: Most everyone has heard the term: the Age of Aquarius. But do you know what it means? Are we in the Age of Aquarius? Did I miss it? Or if not, when will it begin? Do astronomers measure time by it? Do they even care about? Will I get that song stuck in my head? We will take a look at the astronomical background behind the marking of astrological signs. The have a very definite origin in the complex motions of the Earth, the Moon, the planets and the Sun with respect to the background stars. And we will try not to get the song stuck in your head along the way!

Bio: Patrick McQuillan earned a B.S. degree in Physics from the College of William and Mary. His senior research project involved determining the period of variable stars, most notably Alpha Auriga. This was at a time when collecting data meant going to the roof of the physics building, locating the research star by hand, and tracking the star manually by following a guide star in the finder scope. No GPS-auto-guiding-from-a-climate-controlled-remote-location! In the twenty plus years since then, he has explained astronomy to the general public as a Planetarium Director, the Education Manager for Challenger Center for Space Science Education, a NASA Solar System Ambassador, and currently explains Earth Science as Education and Outreach Specialist for IRIS. You can view current earthquake activity using the Seismic Monitor located on the IRIS website.

Today’s Sponsor: This episode of ‘365 Days of Astronomy” is sponsored by the American Astronomical Society, the major organization for professional astronomers in North America, whose members remind everyone that One Sky Connects Us All. Find out more or join the AAS at


Hello, I’m Patrick McQuillan, Education and Outreach Specialist with IRIS, the Incorporated Research Institutions for Seismology, a NASA Solar System Ambassador and a former Planetarium Director. Welcome to the February 27th edition of the 365 Days of Astronomy podcast. I’m sure you’ve heard the phrase “the Age of Aquarius.” In case you’ve forgotten, it has something to do the night sky.

You know like:

When the Moon is in the 7th house

and Jupiter aligns with Mars

Then peace will guide the planets

And love will steer the stars.

This is the dawning of the Age of Aquarius.

Aquarius….Aquari….ooh, sorry about that. Although, if you really want to get the entire song stuck in your head, it is available on iTunes.

Anyway, if you believe the song, its like the beginning of the Age of Aquarius and peace, love and prosperity are going to rule the universe. Well, we are heading towards what astrologers call the Age of Aquarius, but don’t hold your breath for that happy little universe of yours. We don’t actually enter the Age of Aquarius for another 600 years.

Bummer dude!

Its all the fault of precession. Precession is the wobble in the tilt of the Earth’s axis.

I know what you’re saying. Whoa. The Earth isn’t wobbling. I would feel that.

It takes 26,000 years for the Earth to complete one wobble, so it is a very slow process. But it is responsible for the changing astrological ages. It is also responsible for throwing off everything that astrology is supposedly based upon.

If you go out and watch the night sky on any evening you will quickly come to the conclusion that it is not doing anything. It is just sitting there.

While the groups of stars that we can see at night do change over the course of a year, due to the Earth’s rotation and revolution, the locations of the stars relative to each other do not change much over our lifetimes. The patterns we see today are basically the same ones that were seen 6000 years ago.

Against this background of fixed stars, the ancients noticed that a handful of objects did change their positions. One of the easiest to find is the object closest to Earth: the Moon.

Everyone knows the Moon changes its position and shape each night, repeating the process each month.

The ancients also noticed that the location of the Full Moon against the fixed stars changed by one constellation each month. A cycle that repeats year after year. The Full Moon appears in front of 12 different constellations. And in a similar fashion, it was noticed that the Sun also changes its position relative to the fixed stars, and passes in front of the same 12 constellations.

The Sun, Moon and lets not forget the planets, follow a similar path across the sky. This path is known as the ecliptic. The ecliptic traces the plane of the solar system. As the Earth and other planets orbit the Sun, and as the Moon orbits the Earth — the Sun, Moon and planets will appear at different locations on or near the ecliptic.

The constellations along the ecliptic gained special significance to the ancient astrologers because all the celestial objects that moved passed in front of these few constellations year after year. The ancient Greeks called these constellations the zodiakos kyklos, the circle of animals. Today they are commonly referred to as the zodiac constellations.

According to astrology, the constellation that the Sun was in on the day of your birth will have a great influence on the rest of your life.

Let’s look at the astrology column in the newspaper for today. If you were born today, February 27, you would be a Pisces. Pisces are anyone born between February 20 and March 20. The horoscope for Pisces says,  “Universal secrets will be revealed to you.”

Hey, we may learn something yet.

If we went out side today, and if we could dim the Sun enough so that the stars were visible, we would see that the Sun in NOT located in the constellation of Pisces. On February 27, the Sun is located in the constellation of Aquarius.

Since we have no way to dim the Sun and since looking directly at the Sun will damage your eyes we need a safe way of seeing this.

A number of good planetarium software programs are available for free on the internet. Just google “planetarium software programs online”. One of my favorites is Stellarium.

Using the software program’s controls, set the date to February 27, turn on the constellation outlines, and locate the Sun.

Hey, you will notice something’s wrong. February 27 is located in the astrological sign of Pisces, however the Sun, on February 27, is located in the astronomical constellation of Aquarius.

I hear what you are saying, “that’s way wrong dude!”

That’s the effect of precession, dude!

Two thousand years ago – when the birth dates corresponding to each sign were determined – the signs matched the constellations. Since then the wobble of the Earth’s axis has moved the location of the Sun over by one constellation.

A further change from ancient times is the location of the Sun on the first day of Spring.

Using your planetarium software, turn on the line called the celestial equator. This line marks the projection of the Earth’s equator out into space.

Compare the celestial equator to the ecliptic. You will notice they do not line up. That is because the Earth is tilted 23 and a half degrees.

Even though they don’t line up they do cross at two points, once in March and once in September. In the northern hemisphere, the first day of Spring officially begins when the Sun, traveling northward on its apparent path, crosses the celestial equator. In  2009 the Sun reaches this point on March 20.

The Earth is doing all the moving as it orbits the Sun, of course. But, from our perspective on the surface of the Earth, it appears as though the Sun changes its position.

Set your planetarium program to March 20, 2009. Then find the Sun. I’ll wait for you.

Ok, here we are. This point is known as the vernal equinox. Two thousand years ago, the vernal equinox was located in the constellation Aries the Ram. It was the Age of Aries. The vernal equinox moves westward through the stars due to precession.

Today it is in Pisces the Fish and this is the age of Pisces. I bet you can guess which constellation is west of Pisces.

That right! Aquarius!

That is why we are heading towards the dawning of the Age of Aquarius.

Precession will carry us there, and in the process, move the constellations even further away from the correct birth sign dates. Until they line up again 24,000 years from now. Which is WAY too long to have that song stuck in your head!


End of podcast:

365 Days of Astronomy
The 365 Days of Astronomy Podcast is produced by the New Media Working Group of the International Year of Astronomy 2009. Audio post-production by Preston Gibson. Bandwidth donated by and wizzard media. Web design by Clockwork Active Media Systems. You may reproduce and distribute this audio for non-commercial purposes. Please consider supporting the podcast with a few dollars (or Euros!). Visit us on the web at or email us at Until tomorrow…goodbye.