Tom Burns: Jupiter, astrology and the constellations


Anyone who has taken a quick trip outside during morning twilight lately has seen the planet Jupiter shining brightly in the east. It’s hard to miss above even-brighter Venus. So go out and look.

Then, that evening, go out just after dark and view the V-shaped head of Taurus the Bull, and its bright star Aldebaran as it rises in the east.

I take particular notice because Jupiter was in Taurus on the day I was born. The last time the planet passed through the constellation, there was a period around my birthday when Jupiter was perched precisely on the Bull’s shoulders.

Now, they are on opposite sides of the sky, with Jupiter in the constellation Leo.

All of this points to the rather strange relationship between astrology and astronomy.

Jupiter’s occasional presence in Taurus or Leo is no surprise. Because the planets orbit the sun, they slide along a band of constellations called the Zodiac. Jupiter takes about a dozen years to orbit the sun and thus about the same time making one passage around the sky. The planet is bound to spend just under a year in Taurus before it moves on.

The ancients were unaware of the true motions of the planets around the sun.

Jupiter was the king of the gods. Presumably, he could meander around the sky any way he wanted. Why does he spend so much time in, say, Taurus?

One explanation consisted of Jupiter’s frequent marital infidelities, despite the watchful eye of Juno, his rightfully jealous wife. One ominous day he fell in lust with Io, the stunningly beautiful daughter of the river god Inachos. Io couldn’t resist the charms of Jupiter. Power, as Henry Kissinger once said, is a powerful aphrodisiac. Still, Io had to be cautious. Juno could make powerful mischief for Io if she found out. Jupiter was not so squeamish. Io was a priestess in Juno’s temple, which added to the allure as far as Jupiter was concerned.

When Juno inevitably found out, she turned poor Io into a white heifer, a relationship killer if there ever was one. Because she didn’t trust her philandering husband even under these strange circumstances, she also instructed Argus, a giant with 100 eyes, to watch the imprisoned heifer. Argus made a good prison guard. Because a few of his eyes were always open, he didn’t get a whole lot of sleep.

Jupiter figured the least he could do was to free Io from prison. He demurred at the thought of doing his own dirty work, so he send Mercury, the fleet-footed messenger of the gods, to kill the huge, hairy insomniac.

This was no mean task. Argus literally had eyes in the back of his head. In this case, lightning speed triumphed over 20-20 vigilance. Mercury lopped off the giant’s head before he knew what hit him.

Juno was furious, of course, but she couldn’t do much to punish her more-powerful husband. In one version of the myth, she contents herself by placing the slain giant’s 100 eyes in the sky as the tail of the constellation, Pavo, the Peacock.

In another version, Io escapes to Egypt, where Jupiter returns her to human form.

As repayment for her considerable troubles, the god allows her to give birth to Epaphus, a lovely daughter who eventually becomes ruler of the Nile Valley.

In my favorite rendition of the story, Juno exacts a certain measure of revenge.

Just as Io is freed from imprisonment, Juno sends a gadfly to bedevil the heifer.

Io jumps into the sea to escape the annoyance. She tries to swim away, and she can be found in the sky immersed in the ocean up to her shoulders to this very day.

Despite his many flaws, Jupiter is, if nothing else, loyal to his fallen lovers. As he moves among the stars of the Zodiac, he is driven occasionally to revisit the beauty of the constellation. He will do so again from May 2023 to May 2024.

I’ve always wondered about the logic of astrology. How is it that a given god’s presence influences our conduct on Earth? I asked my second favorite classical scholar, Donald Lateiner, for an answer when he was at Perkins recently. (Sorry, Don. My favorite classicist is my daughter, Krishni.)

He speculated about an old notion of the Roman Stoic philosophers. They believed that humans were a “divine spark” of the gods. Everything that affects them emotionally is bound to affect our attitudes and behavior, that is, if you still believe in the old gods.

Of course, astronomers no longer believe in Jupiter. The point of light we see is a ball of liquid hydrogen and helium and not the grand deity of old.

However, remnants of the old beliefs remain. Otherwise rational people still check their horoscopes every day. If you are one of them, you might consider rereading this column to find out where you beliefs come from.

Even modern astronomy is strangely tied to the old traditions. The early astronomers who discovered and named their telescopic discoveries knew the old mythology well. Binoculars reveal four, tiny points of light huddled around the planet. They are the four brightest moons of the erstwhile god. One of them is called Io, who still orbits the planet in eternal fidelity to her lost love.

Tom Burns


Tom Burns is director of the Perkins Observatory in Delaware.

No posts to display