The changing face of the moon has long been documented by artists. In the early 1600s, the introduction of the telescope allowed for detailed sketching of lunar features at the eyepiece. The most celebrated early telescope sketcher was Galileo Galilei. His artistic training allowed him to understand that the jagged appearance of the lunar terminator (day/night line) seen in the eyepiece was due to the topography of craters, mountain, and ridges on the moon. These irregular shadows on the moon had puzzled earlier observers that considered the moon to be a flat disk with markings on it.
After being photographed at the end of February, showing off 3 green tails, comet 2P/Encke prepares for the final act of this apparition: a week-long plunge through the stars of Pisces toward the western horizon and perihelion. At the end of February the comet had brightened to almost 8th magnitude. Encke’s orbit this week takes it between the earth and sun — which will cause it to reach peak brightness and then disappear from sight . Use the horizon diagrams here to help you spot it. Continue reading “Comet 2P/Encke’s Blaze of Glory”