Dear Skywatchers,

How many moons does Jupiter have? It seems like a simple question with a simple answer. And, as of today, astronomers have discovered 72.

But astronomers discover more Jovian satellites every year and are pretty sure more exist. And that story of discovery is a lot more interesting than a mere number.

Over 2300 years ago, Chinese astronomer Gan De recorded observations of Ganymeade. About 400 years ago, Galileo used his 20x telescope to see Jupiter’s four largest moon. But as late as 1999, astronomers had only discovered 13. In recent years, astronomers have used high-tech measuring devices to discover the previously undiscoverable.

And this story of discovery will continue. So, expect someday to tell your grandkids about the good old days when Jupiter only had 72 moons.

Sincerely,

Mr. Heimbuck