Saturn and Galileo

Sat­urn has returned to our cen­tral Ohio sky at last. No astro­nom­i­cal sight is more breath­tak­ing, even in a small tele­scope, than Saturn’s celes­tial hat brim. Around 10 p.m., look for the ringed planet low in the south­east­ern sky as a yel­low point of light.

Most folks imag­ine that sci­ence in gen­eral and astron­omy in par­tic­u­lar is filled with calm, single-minded peo­ple who quest unceas­ingly after truth. The fact is that the his­tory of astron­omy is filled with weird­ness on a cos­mic scale. Even the great­est dis­cov­er­ies are often cloaked in dark por­tents and strange events.

Such was the case with the dis­cov­ery of the rings of Saturn.

Sat­urn is the far­thest planet from the sun vis­i­ble to the unaided eye. At about a bil­lion miles away from our daystar, it takes almost 30 years to make one orbit. As a result, it moves very slowly against the back­ground stars, a motion that our ancient fore­bears saw as stately and beautiful.

The ancients had no tele­scopes, of course, so the rings that gir­dle the planet were unknown to them. They saw the plan­ets as per­fect and unchang­ing, their motions pre­dictable. To say oth­er­wise was heresy, a blas­phemy against the gods who cre­ated them.

That cir­cum­stance was true even up to the early 17th cen­tury, when the inqui­si­tion still wielded its velvet-gloved fist over the intel­lec­tual life of Europe.

Galileo Galilee was a fol­lower of the Coper­ni­can model of the cos­mos, which placed the sun at the cen­ter and the plan­ets revolv­ing around it. The hier­ar­chy of the Catholic Church still espoused the old Ptole­maic model, which placed Earth at the cen­ter. They saw the heav­ens as unchang­ing, per­fect reflec­tions of the power of a per­fect God.

But it was not Galileo’s sun-centered model that got him in trou­ble with the Church. You see, Galileo was a sci­en­tist. He believed that direct obser­va­tion of the uni­verse pro­duces our best under­stand­ing of its work­ings. The Church believed that the senses can trick us. Only divine rev­e­la­tion pro­duces true understanding.

When Galileo first pointed his tiny tele­scope at Sat­urn, he saw some­thing that shocked him so much that he had to tell the world: “SMAISMRMIMLEPOETALEUMIBUNENUGTTAURIAS,” he wrote.

Ha! Fool­ish Galileo. That con­clu­sion is, as you can clearly see, totally incorrect.

Con­fused? You should be. This cryp­tic mes­sage is an ana­gram — of a Latin sen­tence, no less. It says, “Altissi­mum plan­e­tam tergeminum obseruani.”

Galileo’s tele­scope was so poor by today’s stan­dards that he had not seen the rings. Instead, he had observed two cir­cu­lar lumps perched on each side of the planet like plan­e­tary Mickey-Mouse ears. As the Latin loosely trans­lates into Eng­lish, “I have seen the high­est planet [Sat­urn] to be triple in form.”

A few months later, Galileo trans­lated his ana­gram for the world. This and other tele­scopic obser­va­tions of the heav­ens got him into a world of trou­ble. He tried show­ing oth­ers what he had seen, but remem­ber, the senses can deceive us. Tele­scopes are hard to use, espe­cially when you don’t know how to look through them. Galileo’s guinea pigs were the first humans to look through a tele­scope, and they can­not be blamed for see­ing noth­ing at all.

Besides, the plan­ets had to be per­fect rep­re­sen­ta­tions of God’s power. What bet­ter rep­re­sen­ta­tion of per­fec­tion is there than a per­fect, uni­form sphere? Mickey-Mouse ears didn’t exactly fit into that picture.

By 1665, Dutch astronomer Chris­t­ian Huy­gens had devel­oped a bet­ter tele­scope, which he trained on the planet Sat­urn. Here is his star­tling dis­cov­ery in his own words: “aaaaaaacccccdeeeeeghiiiiiiillllmmnnnnnnnnnooooppqrrstttttuuuuu.”

Ha! In honor of Galileo, Huy­gens had pub­lished his obser­va­tions as another Latin ana­gram, which in Eng­lish reads, “Sat­urn is gir­dled by a thin, flat ring, touch­ing it nowhere, and tilted to the eclip­tic.” I’ll leave it to you ana­gram fans to fig­ure out what the Latin is.

Tom Burns is the direc­tor of Ohio Wes­leyan University’s Perkins Obser­va­tory, and he would be very happy to answer your ques­tions or sell you a ticket to one of its upcom­ing Friday-night pro­grams. He can be reached at tlburns@owu.edu or 740–363-1257.

Posted by Tom Burns on Apr 8 2012. You can follow any responses to this entry through the RSS Feed. Comments can be made below.