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Astronomy Picture of the Day - Triple Transit and Mutual Events
APOD.NASA.gov ^ | 21 Aug, 2021 | Image Credit & Copyright: Christopher Go

Posted on 08/21/2021 2:26:49 PM PDT by MtnClimber

Explanation: These three panels feature the Solar System's ruling gas giant Jupiter on August 15 as seen from Cebu City, Phillipines, planet Earth. On that date the well-timed telescopic views detail some remarkable performances, transits and mutual events, by Jupiter's Galilean moons. In the top panel, Io is just disappearing into Jupiter's shadow at the far right, but the three other large Jovian moons appear against the planet's banded disk. Brighter Europa and darker Ganymede are at the far left, also casting their two shadows on the gas giant's cloud tops. Callisto is below and right near the planet's edge, the three moons in a triple transit across the face of Jupiter. Moving to the middle panel, shadows of Europa and Ganymede are still visible near center but Ganymede has occulted or passed in front of Europa. The bottom panel captures a rare view of Jovian moons in eclipse while transiting Jupiter, Ganymede's shadow falling on Europa itself. From planet Earth's perspective, similar mutual events, when Galilean moons occult and eclipse each other, can be seen every six years or so when Jupiter is near its own equinox.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: nasa
To be added or removed from the Astronomy Picture of the Day ping list please send me a request via "Private Reply" (Mail).

For more detail go to the link and click on the image for a high definition image. You can then move the magnifying glass cursor then click to zoom in and click again to zoom out. When zoomed in you can scan by moving the side bars on the bottom and right side of the image.

1 posted on 08/21/2021 2:26:49 PM PDT by MtnClimber
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To: MtnClimber

2 posted on 08/21/2021 2:27:05 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: 21stCenturion; 21twelve; 4everontheRight; abb; AFB-XYZ; America_Right; AZ .44 MAG; BBB333; ...
Pinging the APOD list.

🪐 🌟 🌌 🍔


3 posted on 08/21/2021 2:27:43 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: MtnClimber

Ganymed is almost as big as the planet Mars - and it’s absolutely dwarfed by Jupiter. Amazing pictures.


4 posted on 08/21/2021 2:56:15 PM PDT by AnotherUnixGeek
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To: MtnClimber; All

Jupiter is by far my favorite planet, other than Home Sweet Home. She has the most lovely names for her moons, too!

Io, Europa, Ganymede and Callisto.

I’m starting a movement to call Earth’s Moon, ‘Selene’ which is Greek for ‘Moon.’

Yes, I know. Until Galileo discovered Jupiter’s moons, we thought Earth was the only planet WITH a Moon, so there was no need to name it.

But still. She DESERVES a pretty name, don’t you agree?

Let’s make this happen, People, LOL! :)


5 posted on 08/21/2021 3:07:00 PM PDT by Diana in Wisconsin (I don't have 'Hobbies.' I'm developing a robust post-Apocalyptic skill set. )
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To: AnotherUnixGeek

Incredible pictures!


6 posted on 08/21/2021 3:08:27 PM PDT by telescope115 (Proud member of the ANTIFAuci movement. )
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To: Diana in Wisconsin

Selene it is. :-)

In addition to its moons, Jupiter also provided one helluva show when Shoemaker-Levy 9 crashed into it. Ours were the first human eyes to ever observe such a stupendous event.


7 posted on 08/21/2021 3:17:41 PM PDT by AFB-XYZ (Stand up, or bend over)
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To: AFB-XYZ

I was out in my yard watching that event. Couldn’t see much (only had a 8 inch Newt at the time), but, you could see the smudges!


8 posted on 08/21/2021 4:10:07 PM PDT by Conan the Librarian (Conan the Sailing Librarian)
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To: AFB-XYZ

Beau gave me the choice of gifting me a smart phone or a telescope for my Birthday this year.

I’m taking the telescope! :)

We are now buried deep in the SW hills of Wisconsin; no city lights at all. When late August rolls around, I can see The Milky Way from my front porch, and the ‘falling stars’ in August (Leonid meteors) are always plentiful and awe-inspiring.

When my boys were young we camped out on our deck (a different farm, well outside of City Lights too) many summer nights and we would count ‘falling stars’ until we fell asleep. We made it to 200 one summer night.

Life Was/Is Good, thanks to ‘The Heavens.’ :)


9 posted on 08/21/2021 6:36:03 PM PDT by Diana in Wisconsin (I don't have 'Hobbies.' I'm developing a robust post-Apocalyptic skill set. )
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