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This year the Earth is still close to the equatorial plane of Jupiter, so transits and shadow transits of the Galilean satellites will occur quite frequently. Jupiter has moved north of the ecliptic and so is climbing higher in our skies this year.
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The morning of the 9th August 2022 and a double, shadow transit. These double transits are uncommon but not rare. Here Io and Ganymede throw shadows onto the planet. The two pictures are almost 46 minutes apart and you can see the progress of the event. In the second picture, Ganymede's shadow is just moving off the planet and Io is transitting. Resolving a small bright satellite against the bright planet is always difficult and I am not sure I have ever resolved one (There is no subtle reason for using drizzling for the second picture. It requires four times as many frames to get the same reduction in noise, so I collect images for twice as long and use most of them. I wasn't sure whether the rotation of Jupiter would blur the details in 2 minutes. It seems not.) Date and Time: 9 August 2022 02:08 and 02:53 Telescope: LX200-10 Camera: DFK 21AF04 Exposure: 1/250 sec Processing : Registax5 : at 02:08, 829 frames stacked, Wavelets 1-2 = 30. Focus Magic 4 at 02:53 2532 frames stacked with drizzle, Wavelets 1-2 = 30, Reduction ×2. Focus Magic 4 |
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