Jovian transit

[bkm2304 (Richard Brown)]

Hi All,

I've just been looking at Jupiter with the 16" and noticed what seemed to be a moon and shadow transiting. It was not a Galilean moon as these were all well away from the planet disc. I assume the shadow belonged to the satellite I saw - if indeed it was a satellite. Anyone got any ideas?

[ballaratdragons (Ken)]

A satellite wouldn't cast a shadow on Joop. Strange

Here are the locations of the Galilean Moons at the moment:

[iceman (Mike)]

Ken is right, it certainly would not be a satellite shadow, and there were no galilean moons transiting at around 10pm AEST.

I suggest it may have been a dark feature on Jupiter itself. Take a look at mine and Anthony's latest images - there are many dark spots and barges that can look like a shadow or a moon at low resolution.

[JimmyH155]

Thats funny.... last weekend I too had a peek at Joops through my 12"LB and I SAW THE SAME THING I counted the moons and I could see 4 - all away from Joops. I even shone my torch down the tube to see if there was muck on mirror, then I put in a different eyepiece, and it was still there a distinct round completely black shadow - towards the edge. I thought arent I clever - I have seen a transit but there are only 4 big moons arent there??? and this was the fifth what was it??

[bkm2304 (Richard Brown)]

Thanks for the replies lads. Let me clarify the term satellite as I used it!! I mean orbiting moon not man made device sent up to take photos of Jupiter! My suspicion is that it is a lesser moon - satellite transiting and I caught it in flagrante de licto!

The seeing was at times superb and i saw detail on Jupiter i had not seen previously. very fine bands and festoons.

Richard

[iceman (Mike)]

Hi Richard

Although Jupiter has over 60 moons, only the 4 galilean moons cast shadows on the planet that we can observe. The rest are so tiny in comparison that not even hubble would resolve them.

[bird (Anthony Wesley)]

There is a prominent dark storm close to the GRS, I'm sure it would look like a moon shadow, but very small, maybe that was what you saw?

The recent images of Jupiter in the solar system thread show this feature.

regards, Bird

[JimmyH155]

Well I just looked at those photos on the solar thread and yes one of those photos shows exactly what I saw - a large black spot not far from the edge. (not the small one near the GRS) So it was just a storm was it? Completely black?? Seems strange.......
And we saw it because the seeing was so good
You dont think there are aliens up there do you?? Massing for an invasion of Earth?

[bkm2304 (Richard Brown)]

Hmmm.... maybe it was the storm. Thanks for the info re: only 4 moons cast shadows. But I think your comparison between the Lightbridge and the Hubble is a bit unfair - afterall the Hubble is getting old!