Montage Covering One Io Orbit, Derived From Marble Movie Stills

2016-08-29 20:14 UT
Credit : NASA / SwRI / MSSS / Gerald Eichstädt
Submitted By : Maquet-80
Mission Phase : PERIJOVE 1

Calculating difference images within the Marble Move sequence allows separation of Jupiter from its moons into two images.

This image is a montage composed of the moon component of 171 Marble Movie images, and one Jupiter component of the same sequence.

In this north-up version, Juno looks to Jupiter from "below" the orbital plane of the Galilean moons, close to crossing it.

So this image shows the orbits of the moons almost edge on.

The image visualizes the 1:2:4 orbital period of Io, Europa, and Ganymede by showing a full ellipse for Io, a half one for Europa, and a quarter of an ellipse for Ganymede, the latter cropped a bit at the left.

The trajectory of the fainter moon Callisto is visible.

The trajectory of Io and Europa shows gaps at the left apices of the apparent ellipses, where the moons crossed Jupiter's shadow.

In the upper part of Io's orbit, it's visible in front of Jupiter's night side, whereas in the lower part Io is invisible behind Jupiter's night side.

The moons are enhanced in the images only outside Jupiter's dayside. The traverse of the moons over Jupiter's dayside isn't shown in the montage.