From the September 2009 issue

Glenn Chaple’s Observing Basics: The Medicean stars

November 2009: Jupiter's four largest moons were evidence that not all celestial bodies orbit Earth.
By | Published: September 28, 2009 | Last updated on May 18, 2023
November 2009 Sidereus Nuncius
In drawings from Sidereus Nuncius, Galileo depicted Jupiter’s moons as asterisks. The Italian scientist discovered Io, Europa, and Callisto January 7, 1610, and Ganymede 6 days later.
Linda Hall Library of Science, Engineering, & Technology

You’re a newcomer to backyard astronomy. You’ve already used your telescope to explore the Moon, marveling at its majestic cratered terrain. The experience whetted your appetite to probe deeper into space. What next?