Connect to share and comment

Looking through Galileo's eyes

Modern astronomers marvel at what Galileo Galilei discovered with his 17th-century telescope.

The idea to re-create Galileo's telescope originated on the terrace of the Institute and Museum of Science in Florence. Museum director Paolo Galluzzi took one of the two original remaining Galilean telescopes on the museum roof to inspect the night sky.

"I have to admit, I saw very little through Galileo's telescope," Galluzzi said. “You realize how much he accomplished by trying to see what he did, the way he did.” Galluzzi, for example, strained to spot Jupiter's largest moons, noting how impressive it was that Galileo not only saw them but also calculated their phases.

Galileo's telescope has a very narrow field of view: The moon, for instance, fills it entirely. When Galileo spied the blanket of stars in the Pleiades and the Milky Way, he "got tired" of trying to sketch them all, Palla said, creating a challenge for researchers to reconstruct his accurate but incomplete observations.

Galileo also had poor eyesight and vision problems. To know precisely what Galileo saw, Galluzzi wants to open his tomb in Florence to examine his DNA. If authorities grant permission, it's up to Peter Watson, bespectacled president of the International Council of Ophthalmology, to determine whether Galileo suffered from a condition called creeping angle closure glaucoma. Galluzzi believes it might explain why Saturn has lateral bulges and not rings in Galileo's sketches.

To follow in Galileo's footsteps, the Arcetri Observatory team uses a photocopy of the original manuscript, which includes eloquent watercolors of moon phases made hastily on scrap paper.
Looking at the heavens as Galileo did requires more that just the equipment, however. On a recent night, thick cloud cover made pointing any telescope futile. And to minimize interference from light pollution, Stefanini spent long nights stargazing from his home nestled in the Tuscan countryside.

“Even the best equipment doesn't guarantee much with astronomy,” said Francesco Palla, director of the observatory. “Patience is about 90 percent of what we do.”

While waiting for the sky to clear, Palla gives an evening visit to a group of Florentine 5th graders. In response to questions from the soft-spoken director, hands dart up to answer that the earth revolves around the sun, what the Milky Way is and how many stars there are in Orion's belt — the same principles that got Galileo excommunicated.

When the kids file out 90 minutes later, the clouds have parted enough to try to frame the moon in the model of Galileo's telescope.

Squinting to overcome my own nearsightedness, the rough surface of the moon in its first phase finally comes into view. It's a whole new world.