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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 the most awe-inspiring eclipses taking place in our Solar System.  We also set them up 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".

Unless noted otherwise, the events identified 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.

Remember: you can press the   M   key to toggle Moon Labels on and off .

JUPITER

Jupiter is now in that part of its orbit where its equatorial plane, and the orbital planes of the four Galilean moons, are increasingly tilting with respect to the Sun.  While Io, Europa and Ganymede all produce solar eclipses each time they orbit Jupiter, this is not true of Callisto.  Callisto's increasingly tilting orbit has made it incapable of casting its shadow on Jupiter since last December.  This will be the case until 2013!

Like last month, because Io, Europa and Ganymede fail to "converge" between Jupiter and the Sun this month, no simultaneous solar eclipses (i.e. involving more than one major moon) occur in March.  Nonetheless, there are times when two or more Galileans are visible near Jupiter.  Here are highlights of the 31 solar eclipses that Io, Europa and Ganymede spawn in March, while the shadow of Jupiter stretches to the east (left).  Whenever Io, Europa and Ganymede enter the Jovian shadow this month, they do so hidden by Jupiter.  Even so, their sudden emergence from that huge shadow is generally visible.

With the Galilean info below, it is easy to see why some events involving more than one moon repeat.  This info also lets you predict when events may recur.
Periods:
   Io:  1.769 days
   Europa:  3.551 days
   Ganymede:  7.155 days
   Callisto:  16.69 days
Resonances:
   Io & Europa: 2 to 1
   Io & Ganymede: 4 to 1
   Europa & Ganymede: 2 to 1

• Mar 1: after Europa casts its shadow, Io, Callisto and then Ganymede approach from the east (left)  (1.6.x)   (1.4.1)
• Mar 2: Io passes Callisto and Ganymede as the latter casts its shadow  (1.6.x)   (1.4.1)
• Mar 3: Io passes Europa east of Jupiter  (1.6.x)   (1.4.1)
• Mar 4: Io passes Europa east of Jupiter, but this time each is going in the opposite direction  (1.6.x)   (1.4.1)
• Mar 5: Io passes Ganymede and then follows it behind Jupiter  (1.6.x)   (1.4.1)
• Mar 9: while casting its shadow, Ganymede passes Io; later Ganymede passes Callisto and Europa  (1.6.x)   (1.4.1)
• Mar 10: with Europa further east, Io and Callisto are less than one planet diameter east of Jupiter  (1.6.x)   (1.4.1)
• Mar 18: Io and Callisto are less than one planet diameter east of Jupiter  (1.6.x)   (1.4.1)
• Mar 23: while Ganymede passes "in front of" Jupiter and casts its shadow, Io passes behind  (1.6.x)   (1.4.1)
• Mar 27: Io Ganymede and Callisto are east of Jupiter  (1.6.x)   (1.4.1)

SATURN

Like Jupiter, Saturn is now in that part of its orbit where its equatorial plane, as well as the orbital planes of its major equatorial moons, are all tilting more and more relative to the Sun.  So fewer and shorter eclipses will occur on the ringed planet for some time. 

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 27 and no solar eclipses on Saturn in March.  In addition, version 1.6.x reveals one double simultaneous solar eclipse this month.  But you'll notice that Dione is casting its shadow further and further south, and before long it will not be able to create a solar eclipse on Saturn for awhile.

To aid in your viewing, here are the periods of Saturn's major moons.  These do not exhibit the resonances that Jupiter's Galileans display.  Still, you can use this info to predict subsequent eclipses of a single moon.
   Tethys:  1.888 days
   Dione:  2.737 days
   Rhea:  4.518 days
   Titan:  15.95 days
   Iapetus:  79.33 days

• Mar 2: Tethys casts its shadow on Saturn, as it now does about every 2 days  (1.6.x only)
• Mar 3: Dione casts its shadow on Saturn, as it now does about every 2¾ days  (1.6.x only)
• Mar 19: 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!