Triple Shadow Transit across Jupiter Tonight

Triple shadow transits, where three moons cross the face of Jupiter, happen only once or twice a decade. Catch the show tonight.

Triple transit across Jupiter
Three moons will cast their shadows on the face of Jupiter tonight, a rare event that only happens once or twice a decade. (Note: this image is a simulation of what you would see tonight from WinJUPOS.)
If you have a telescope, you'll want to take a look at Jupiter tonight (October 12th) between 4:32 and 5:37 Universal Time. (That's 12:32 to 1:37 a.m. Saturday morning, Eastern Daylight Time.) You'll see a rare occurrence: three moons will be casting their inky black shadows on the gas giant’s cloud tops.

The show begins just after 3:05 UT with Callisto’s elongated shadow entering the Jovian disk near the planet’s south polar region, followed by Europa’s shadow just below the South Equatorial Belt at 3:25. Io’s shadow joins the party at 4:32.

Observers in Europe and Africa are best placed to witness the entire event with Jupiter high in the sky. Observers along the East Coasts of North and South America will be able to catch the tail end of the transit with Jupiter low in the East. This event should not be missed — triple shadow transits are only visible once or twice a decade. Fortunately because the shadows are so dark, they should be easily visible even with the planet low on the horizon.

8 thoughts on “Triple Shadow Transit across Jupiter Tonight

  1. Joe Stieber

    Sean’s timings above are in line with predictions from most sources. However, S&T’s online "Jupiter’s Moons" utility has the triple shadow event starting at 04:28 UT when Io’s shadow enters the Jovian disc (a few minutes early), and ending at 05:06 UT when Callisto’s shadow leaves the disc — half an hour early!

  2. timothy kammrad

    above it says, That’s 12:32 to 1:37 a.m. Saturday morning, Eastern Daylight Time. If it read, 00:32 to 1:37 it would be more clear.

    Then it sais, Observers along the East Coasts of North and South America will be able to catch the tail end of the transit with Jupiter low in the East.

    At thoses times jupiters is at around 35 degress high.

    I watched at the indicated times in the -5 east time zone,and didnt see it 🙁

  3. Dale

    How could you have possibly seen anything when you posted @ 11:14pm? The show don’t start until… By show I mean the 3 shadow show!

    The times are CLEARLY stated above, and the times in the article from beginning to end are not off by much, the END time for the 3 shadows on the face at 1 time is correct, 1:37 AM is when the first of the 3 shadows has crossed the face, and the start time of 12:32 is what I have had written on my observing calander since February, so if you went out at say 12:45 and stayed out until 1:25 you will have seen the 3 shadows.
    Anytime before like say 11:14, you will only see 2! it is the 3rd shadow that makes this a special event, so missing the last shadow is pretty dumb!
    BUT timmy, you have 2 more chances (1) in 2014 and (1) more in 2015…. I could get you the times but it doesn’t look like you listen well anyway so you can look them up yourself!

  4. Steve

    Dale….easy on Timothy. If you had done your due diligence, you would have noticed that Dale posted at 11:14pm PACIFIC time. I WILL do the math for you…that’s 0214 Eastern time.

    Please save your sophomoric commentary for other websites. This website is for civil conversation and education among astronomy buffs.

    Timothy…please return and ask any questions you feel relevant.

    All the best.


  5. Steve BryantSteve Bryant

    What is the nature of the telescope that took the picture of Jupiter in the article above? What telescope, available for purchase, would permit such an image? I suspect that it would be quite large and expensive, yes?

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