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Various astronomical "shadow events" occur throughout the Solar System!  This month's more interesting ones are featured here.

SHADOW WORKS

Here we highlight (and set up) the most awe-inspiring eclipses taking place in our Solar System, so that all you need to do is click on their links.  Don't forget that you can generate lists of Earth's, Jupiter's, Saturn's, Uranus's, Neptune's and even Pluto's eclipses, using CELESTIA's own built-in "Eclipse Finder."  You'll find it in the program's menu under "Navigation".

All events listed below are displayed as if viewed from Earth, their magnifications shown in parentheses at the lower right of CELESTIA's window.  Events involving more than one moon are often cyclical, so usually only the first example is given, and then the period of the cycle.

JUPITER

As depicted in CELESTIA, here are highlights of the 30 solar eclipses that Io, Europa, Ganymede and Callisto—the "Galilean" moons of Jupiter—produce in April.  You'll see simultaneous solar eclipses this month, as two Galileans cast their shadows on Jupiter at the same time.  As always, examples of the Galilean moons moving into Jupiter's shadow are also included.

• Apr 2: Io casts its shadow on Jupiter just before Europa disappears into Jupiter's shadow; nearly the same will repeat about every 3½ days; meanwhile Ganymede is already in Jupiter's shadow  (1.6.x)   (1.4.1)
• Apr 4: Io having "caught up" to Europa last month, both cast shadows on Jupiter in a cycle that repeats about every 3½ days;  (1.6.x)   (1.4.1)
• Apr 6: Io and Europa continue their cycle from Apr 2, and Ganymede casts its shadow before Io finishes its eclipse; Ganymede repeats this about every 7 days  (1.6.x)   (1.4.1)
• Apr 9: Callisto orbits Jupiter at a great distance so here we see it move behind its parent planet, but we don't see it enter Jupiter's shadow; (run time backward and widen your FOV to see that it has already emerged!)  (1.6.x)   (1.4.1)
• Apr 17: after Ganymede emerges from behind Jupiter, Callisto casts its shadow on its parent  (1.6.x)   (1.4.1)
• Apr 24: look closely to the right, as Ganymede emerges from Jupiter's shadow (which now stretches more and more to the "right" of Jupiter)  (1.6.x)   (1.4.1)
• Apr 25: Io and Europa both cast shadows on Jupiter, but no longer simultaneously  (1.6.x)   (1.4.1)

SATURN

While CELESTIA 1.6.x shows the shadows of Titan, Rhea, Iapetus, Dione and Tethys, version 1.4.1 displays only the shadows of Titan, Rhea & Iapetus.  So, 1.6.x and 1.4.1 respectively show 36 and 7 solar eclipses on Saturn in April.  The highlights are as follows:

• Apr 1: Rhea casts its shadow on Saturn, as it currently does about every 4½ days; then Dione moves into Saturn's shadow  (1.6.x)   (1.4.1)
• April 2: Tethys casts its shadow on Saturn, as it does about every 2 days  (1.6.x only)
• April 3: Dione casts its shadow on Saturn, as it does about every 2¾ days  (1.6.x only)
• April 5: Rhea and Dione cast their shadows on Saturn simultaneously  (1.6.x only)
• April 7: distant Titan passes "over" Saturn's shadow  (1.6.x only)
• April 15: while Tethys casts its shadow on Saturn, Titan passes in front of Saturn but its shadow misses its parent  (1.6.x only)
• April 19: while Tethys casts its shadow on Saturn, Rhea joins it; Tethys completes its eclipse, then Dione joins Rhea for another simultaneous solar eclipse  (1.6.x only)
• April 25: Tethys and Dione cast their shadows on Saturn at the same time  (1.6.x only)

URANUS, NEPTUNE & Dwarf Planet PLUTO

Neither Uranus nor Neptune will experience eclipses for decades.  Dwarf planet Pluto will experience no eclipses by Charon for about a century!