Before dawn this morning Jupiter was out there, so bright, just in front of the constellation Gemini, the Twins. Galileo was the first to carefully observe Jupiter by telescope and he discovered four Jovian moons, Io, Europa, Ganymede, and Callisto in 1610. When they are in the right orientation, and you are in a fairly dark place, they are visible with a good pair of binoculars. Ganymede is larger than the planet Mercury, Europa has a liquid water ocean, and Io is covered with volcanoes.
The Stars is one of the best reference books for budding astronomers. It starts with both constellation charts and calendar charts, goes on to the zodiac and much, much more. Every home should have this book!
That’s the constellation Gemini, Pollux and Castor, on the book’s cover. This morning, Jupiter was near the right knee of Pollux. If you watch over several nights, you’ll be able to see Jupiter moving into and across Gemini. This is why the Greeks named them planets- Greek for wanderers.
Be sure to check out my earlier post with several very good website links for this unit. And if you want to check out Jupiter, you will have to get up early, a little easier now the time has changed! And a red lens for your flashlight will help keep your night eyes sharp.
Pssst, how many other moons have been discovered orbiting Jupiter, since 1610?