Jupiter's equinox and mutual events of its 4 major moons
The king planet Jupiter reaches its equinox on May 2, 2021, an event that always causes mutual events of Jupiters 4 major moons. Its an eclipse season of the moons.
The king planet Jupiter will reach an equinox an event that happens twice in every 12-year orbit of Jupiter on May 2, 2021. Around Jupiters equinoxes, we on Earth always have an opportunity to see a series of mutual events or you might call them eclipses of Jupiters four major moons. These are the four famous Galilean satellites, Io, Europa, Ganymede and Callisto. The eclipses are already happening. Theyll continue through August 2021. Experienced telescope users will be the ones seeing them; if you get an image, please submit it here. As the four large moons revolve around Jupiter, a moon shadow will sometimes eclipse (fall upon) a different moon. Or the body of one Jovian moon will occult (move directly in front) of another moon. For example, on April 4, Ios shadow will fall upon Europa. The following day April 5 Io itself will occult the moon Ganymede.
It hasnt happened (we havent had a Jupiter equinox) since February 4, 2015. The next eclipse season for Jupiters moons wont come again until around Jupiters next equinox, on December 16, 2026.
These moons orbit in the plane of Jupiters equator. We see the shadows of Jupiters moons eclipsing other moons at or near a Jovian equinox, because thats when the shadows of Jupiters moons align with Jupiters equatorial plane. At times other than near a Jovian equinox, the moon shadows slant relative to the Jovian equator; they angle north or south of the other moons, and no eclipses take place.
https://earthsky.org/astronomy-essentials/jupiter-equinox-mutual-events-moon-2021?