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Old 28-09-2019, 07:14 AM
Tropo-Bob (Bob)
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Callisto's shadow

2019-09-28 21:01:20 +10: Callisto's shadow appears.

I have never seen Callisto’s shadow so look forward to trying to see this tonight. It will be in the polar area, on the edge of the disc. This event is not mentioned in Astronomy 2019, so I am concerned that this is an indication that this may be somewhat difficult to spot.
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Old 28-09-2019, 11:20 AM
Saturnine (Jeff)
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Thanks for the heads up Bob, will have a look this evening. Have wanted to see a shadow transit of Callisto, knowing that they would be rare occurrences.
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Old 29-09-2019, 08:06 AM
Tropo-Bob (Bob)
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The seeing went bad before the event and the clouds rolled over about 20mins in. Shame really, the night had started off so well. Looks like I will have to wait to next year when tilt of the Moons lines up better and the shadow is more likely to be seen.
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Old 29-09-2019, 10:22 AM
Saturnine (Jeff)
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Had a look last night around the time mentioned, tried for about 30 minutes but could not see any shadow. Seeing was reasonable but I was only using a 127mm triplet at 200X, a bit of breeze at times was shaking the scope which wasn't helping the view.
October 10th , early evening has a double shadow transit. Times for the East Coast. Add an hour for Daylight Saving for Vic and NSW
Europa Shadow Ingress @ 18:34 - Egress @ 21:10
Io Shadow Ingress @ 20:55 - Egress @ 23:08
A brief window of 15 mins. when both shadows are on the disc though they will be on opposite sides and very close to the edges of Jupiters disc so may be hard to spot.
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Old 10-10-2019, 02:19 PM
Tropo-Bob (Bob)
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Quote:
Originally Posted by Saturnine View Post
.... October 10th , early evening has a double shadow transit. Times for the East Coast. Add an hour for Daylight Saving for Vic and NSW
Europa Shadow Ingress @ 18:34 - Egress @ 21:10
Io Shadow Ingress @ 20:55 - Egress @ 23:08
A brief window of 15 mins. when both shadows are on the disc though they will be on opposite sides and very close to the edges of Jupiters disc so may be hard to spot.
Looking forward to this tonight.
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Old 11-10-2019, 12:16 AM
Saturnine (Jeff)
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As luck would have it, as if this was never going to happen, clear skies all day with Sth / SE winds and as it got toward sunset the clouds blew in. Not an unusual occurrence at this time of the year when there are onshore winds which is common in spring around here.
CFN were predicting a favourable jetstream passing overhead and the scope was set up in readiness of the cloud breaking up and allowing a peek at least. Managed to capture some video for processing but the local winds were affecting the seeing so the image was wavering around . The clouds became thicker and more menacing after that and the radar was showing some showers moving up the coast so that put a stop to any more astro for the night.
Will attach a stacked image of early in Europas' shadow ingress.

500 / 2500 frames, 15ms @ 250 Gain setting, approx 65 f/sec. Registax, 6" f8 Saxon Newt, EQ6, ZWO290mc, 2.5 Powermate
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Old 11-10-2019, 07:58 AM
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I too, had a nervous wait with patches of high cloud lurking around all day. Luckily most had dissipated by early evening and the sky around Jupiter remained clear.
I managed to see all of the events despite a bit of misadventure. I am camping near Cobram in country Victoria and I set up my scope thinking that Jupiter would be clear of nearby trees around 10pm. Wrong. At 9.35 it was clear that I needed to move. I quickly moved everything about twenty feet and all was good for the main event.
I could not pick up the Europa shadow ingress, but several minutes later the sky was dark enough for me to watch Europa form a tiny bulge on Jupiter’s limb at egress.
The Io ingress was nice and clear and I could follow it’s transit for about 10 minutes before it was lost in the surrounding glare of Jupiter’s disc. Europa’s shadow was like a sharp pin point by this time, well past the meridian. I followed Europa’s shadow as it progressed across Jupiter. However it became increasingly difficult to see as it approached Jupiter’s limb.
I then concentrated on the approaching Io shadow. I was able to see it form a notch on Jupiter’s limb. The notch slowly increased and eventually the round shadow was fully within Jupiter’s disc.
Both shadows were now on Jupiter, but I could not see them simultaneously. Io’s shadow was large and an easy target to see. But, Europa’s shadow near Jupiter’s limb was very, very difficult to see. I could just pick it up in moments of better seeing. Io was near mid transit at this point but not visible.
A very pleasing observation.
Vixen NA140SS with LVW5 giving 150x.
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Old 11-10-2019, 08:01 AM
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Nice capture Jeff. Two moons and the shadow. I look forward to your stacked image.

Quote:
Originally Posted by Saturnine View Post
As luck would have it, as if this was never going to happen, clear skies all day with Sth / SE winds and as it got toward sunset the clouds blew in. Not an unusual occurrence at this time of the year when there are onshore winds which is common in spring around here.
CFN were predicting a favourable jetstream passing overhead and the scope was set up in readiness of the cloud breaking up and allowing a peek at least. Managed to capture some video for processing but the local winds were affecting the seeing so the image was wavering around . The clouds became thicker and more menacing after that and the radar was showing some showers moving up the coast so that put a stop to any more astro for the night.
Will attach a stacked image of early in Europas' shadow ingress.

500 / 2500 frames, 15ms @ 250 Gain setting, approx 65 f/sec. Registax, 6" f8 Saxon Newt, EQ6, ZWO290mc, 2.5 Powermate
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Old 11-10-2019, 01:19 PM
Saturnine (Jeff)
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Steve
That is the stacked image, local seeing was bad and was close to disappearing behind the neighbours roofline as well, so that is about as good as I could get.
We may get one more chance before the season is over, a few weeks away but on Sat. 26th Oct according to Astronomy 2019.

Europa shadow transit under way at sunset,
Io Shadow Ingress @ 19:13,
Europa Shadow Egress @ 20:00
Io Shadow Egress @ 21:26
Red Spot Meridian Transit @ 19:55

Jupiter will be getting lower to the horizon by the time the transits finish but clear skies and clear western vistas will be desirable for a good view, naturally. Even get a bonus with Mercury and Venus on show just after sunset and of course Saturn is still up there too.
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Old 11-10-2019, 08:03 PM
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Tinderboxsky (Steve)
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Looking at your image again Jeff, I notice you have captured the last signs of the GRS as it disappears around Jupiter's limb. The mid transit point for the GRS was earlier that evening at about 5.30pm.
So, quite a bit going on in this image.
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