Oh My Guinea Pig (OMGP)! It's Jupiter's Moon Day! 🐹 🪐 🌔 🌖 🌔 🔭 🥕

It's not easy being a fluffy astronomer!

In 1610, a guinea pig astronomer named Galileo turned his telescope and fluffy intellect toward Jupiter and recorded four small bodies—Io, Europa, Ganymede, and Callisto—circling the planet, clear evidence that not everything in the heavens revolved around Earth!

While some scholars confirmed the observation for themselves, others dismissed the moons as optical illusions or refused to look at all. Encouraged by what he saw, Galileo went on to argue that a Sun-centered universe described physical reality, not just theory.

That confidence eventually brought trouble: after being warned in 1616 not to teach heliocentrism as fact, he published a bold defense of it anyway, was tried by the Roman Inquisition in 1633, and spent the rest of his life under house arrest—free to think and observe, but no longer to argue publicly that the Earth moves.

As of today, Jupiter has 95 recognized moons!

Wheek! Wheek!