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

SHADOW WORKS

PARTIAL SOLAR ECLIPSE: 2011 Jun 1

This eclipse begins roughly over Japan at 19:25 UT and will be visible in eastern Asia, northern Alaska and Canada, Greenland and Iceland.  The time of Greatest Eclipse, which occurs over northern Russia, is 21:16 UT.

NASA's  Eclipse Information and Visibility Map

You can view an animation of this eclipse in our   Solar Eclipses thru 2012 video

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 oftentimes cyclical, and the month's first occurence in a cycle is given.  Look at the list of the moons' periods to get a good idea of when a cycle may repeat that month.

Remember: you can press the   M   key to toggle Moon Labels on and off, and press the    ,    and    .    (comma and period) keys respectively to zoom in and out.

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, whose increasingly tilting orbit has made it incapable of casting its shadow on Jupiter since last December.  It will not be able to cast its shadow on Jupiter again until 2013!

Several simultaneous solar eclipses (i.e. involving more than one major moon) occur on Jupiter this month, most produced by Io and Europa.  Here are highlights of the 30 solar eclipses that Io, Europa and Ganymede spawn in June, as Jupiter's shadow now extends to the planet's west (right).

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

• Jun 1: Io and Europa cast their shadows on Jupiter at the same time (as they will do about every 3½days until near month's end), and later pass Callisto  (1.6.x)   (1.4.1)
• Jun 3: Ganymede and Io cast their shadows on Jupiter at the same time, as Europa enters Jupiter's shadow  (1.6.x)   (1.4.1)
• Jun 6: Europa and Ganymede enter Jupiter's shadow as Io casts its shadow on Jupiter; this recurs in about 7 days   (1.6.x)   (1.4.1)
• Jun 10: all four Galileans are visible near Jupiter; Io casts its shadow as Europa disappears in Jupiter's; then Ganymede too casts shadow before Io finishes  (1.6.x)   (1.4.1)
• Jun 19: and Europa cast their shadows as Callisto moves "over" Jupiter  (1.6.x)   (1.4.1)
• Jun 27-28: as Io moves toward Jupiter from the east and prepares to cast its shadow, the other 3 Galileans are to Jupiter's west  (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.  Rhea, Titan and Iapetus have not been able to cast shadows on Saturn since Oct 2010, Feb 2010 and Jun 2007 respectively.  They will not cast their shadows on Saturn again until Mar 2024, Oct 2024 and July 2022 respectively.  In addition, last month Dione cast its last shadow on Saturn until Jul 2023.

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 16 and no solar eclipses on Saturn in June.  In addition, version 1.6.x reveals no double simultaneous solar eclipses this month, as only Tethys produces a solar eclipse on Saturn now for a dozen years!  Moreover, Tethys is casting its shadow further and further south, and before long it too will not be able to produce a solar eclipse on Saturn for some time.

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

• Jun 1: Tethys casts its shadow on Saturn, as it now does about every 2 days  (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!