As the holidays approach, the days shorten, bringing with them our glorious Western Slope night skies. Joining us to celebrate the season is a brilliant cluster of stars, called the Pleiades, or Seven Sisters.
Rising on our eastern horizon, the Pleiades first appears as a cloud-like thumbprint. As your eyes adapt to the darkness, you’ll be able to pick out point-like stars, as many as six or seven.
Look low in southwest as the sky darkens in early December. That brilliant “evening star” is actually not a star, but the planet Venus.
Venus is at its brightest now, in part because it’s relatively close by, only about 35 million miles from Earth. Venus is so very bright that it can cast shadows, and it’s sometimes confused with airplane landing lights, or even reported as a UFO.
For this episode of Western Slope Skies, a look at the moons of Jupiter, and the two Galileos - the man and the machine.
In 1610, Galileo Galilei became the first person to observe another planet, Jupiter, and its 4 largest moons, Callisto, Europa, Ganymede, and Io. For the next 380 years, most scientists believed that those moons were similar to our Moon, that is, rocky spheres without activity or atmosphere.