11.1 day old moon
85.5 percent lit
Tonight is a very big night for Jupiter's moons.
April 17, 2016
By Mike Lynch
...No matter how big or small your telescope is, (click here) you’ll get a kick out of watching Jupiter’s four brightest moons, Io, Europa, Callisto, and Ganymede, as they orbit around their gravitational master in periods of less than two days to just over 16 days. Because of their continual dance, they will constantly be changing positions relative to the disk of Jupiter. Some nights you may see two on one side and two on the other, or three on one side and one on the other, or all four on one side. There are also many nights when you can’t see all four at one time because one or more moons may be behind of or in front of Jupiter from our Earthly vantage. When a moon is behind Jupiter you obviously have no shot at seeing it, but when one is in front of the disk of the planet you may see the dot of its shadow on Jupiter, although you need a moderate to larger telescope to see this. With Jupiter’s relative proximity this month and most of this upcoming fall, you have a chance of seeing a moon shadow on Jupiter even with some of the smaller scopes. It’s worth a try....
