Starship Asterisk*

[quote="neufer"][quote="geckzilla"][quote="Lanier"]

Shadow of an Eclipse on Jupiter is quite different from Earth. There is very little penumbra!
Since the sun is so far away Jupiter Eclipse must be total all of the time. Fuzziness around the shadow edge must be an atmospheric effect.[/quote]
I think the fuzziness is a narrow penumbra. The Sun may be relatively small compared to Europa from Jupiter's viewpoint, but it's still got an angular diameter that occupies a significant fraction of Europa's angular diameter. Around 6 arcminutes for the Sun and around 16 arcminutes for Europa. (Europa may be slightly larger from Jupiter's surface; I'm not sure if Solar System Simulator's measurement is from the surface or center of Jupiter.)[/quote]
The shadow is Io's: Around 6 arcminutes for the Sun and around 32 arcminutes for Io.[/quote]
Thanks. Still enough for a soft shadow edge, right? A 3/16th instead of 3/8th ratio.

[quote="geckzilla"][quote="Lanier"]

Shadow of an Eclipse on Jupiter is quite different from Earth. There is very little penumbra!
Since the sun is so far away Jupiter Eclipse must be total all of the time. Fuzziness around the shadow edge must be an atmospheric effect.[/quote]
I think the fuzziness is a narrow penumbra. The Sun may be relatively small compared to Europa from Jupiter's viewpoint, but it's still got an angular diameter that occupies a significant fraction of Europa's angular diameter. Around 6 arcminutes for the Sun and around 16 arcminutes for Europa. (Europa may be slightly larger from Jupiter's surface; I'm not sure if Solar System Simulator's measurement is from the surface or center of Jupiter.)[/quote]
The shadow is Io's: Around 6 arcminutes for the Sun and around 32 arcminutes for Io.

[quote="Lanier"]Shadow of an Eclipse on Jupiter is quite different from Earth. There is very little penumbra!
Since the sun is so far away Jupiter Eclipse must be total all of the time. Fuzziness around the shadow edge must be an atmospheric effect.[/quote]
I think the fuzziness is a narrow penumbra. The Sun may be relatively small compared to Europa from Jupiter's viewpoint, but it's still got an angular diameter that occupies a significant fraction of Europa's angular diameter. Around 6 arcminutes for the Sun and around 16 arcminutes for Europa. (Europa may be slightly larger from Jupiter's surface; I'm not sure if Solar System Simulator's measurement is from the surface or center of Jupiter.)

Shadow of an Eclipse on Jupiter is quite different from Earth. There is very little penumbra!
Since the sun is so far away Jupiter Eclipse must be total all of the time. Fuzziness around the shadow edge must be an atmospheric effect.

[quote="Boomer12k"]
Our sky's here in Salem, Oregon are sooooo smokey you could not see The Moon!!!! and it smells like a bad BARBECUE... no kidding....yuck.
Last night looked at Moon, you could see wisps of smoke going by...:---[===] *[/quote]

Backpacking in the [url=https://en.wikipedia.org/wiki/Seven_Devils_Mountains]Seven Devils[/url] this weekend the skies went from this the day before
[attachment=1]IMG_9287.JPG[/attachment]
to this last night when we returned.
[attachment=0]IMG_9559 (2).JPG[/attachment]
A different type of "Great Red Spot"! :wink:

[float=left][youtube]https://www.youtube.com/watch?v=0MlN7iVIuhk[/youtube][/float][quote="Ann"]

The Great Red Spot has been steadily shrinking for many years, and certainly since [url]https://en.wikipedia.org/wiki/Pioneer_10Pioneer[/url] visited it in 1973. But the saturation of the Great Red Spot varies, and it has been relatively red recently.[/quote]

Postpartum meteorological depression?

[quote="Boomer12k"]
Why is the red spot not so red in this...nor as big as it seems in some later images? Or am I seeing this wrong?
:---[===] *[/quote]

[float=left][img2]http://www.unmannedspaceflight.com/index.php?act=attach&type=post&id=21649[/img2][c][size=85]Jupiter photographed by Pioneer 10 in 1973, and Jupiter in 2010(?).
Source: http://www.unmannedspaceflight.com/lofiversion/index.php/t6595.html[/size][/c][/float] The Great Red Spot has been steadily shrinking for many years, and certainly since [url]https://en.wikipedia.org/wiki/Pioneer_10Pioneer[/url] visited it in 1973. But the saturation of the Great Red Spot varies, and it has been relatively red recently.

Ann

Oh, a Double Eclipse of Jupiter.... oh, wait... TRANSIT.... OK.... well, actually in this there should be a double eclipse of the SUN on Jupiter, from both Europa and Io... I mean there is Io's shadow, and I assume Europa's is not far behind...

Why is the red spot not so red in this...nor as big as it seems in some later images? Or am I seeing this wrong?

OH, and the "Cheshire Cat" above the shadow of Io....

Our sky's here in Salem, Oregon are sooooo smokey you could not see The Moon!!!! and it smells like a bad BARBECUE... no kidding....yuck.
Last night looked at Moon, you could see wisps of smoke going by...

:---[===] *

[url=https://apod.nasa.gov/apod/ap170905.html][img]https://apod.nasa.gov/apod/calendar/S_170905.jpg[/img] [size=150]Europa and Jupiter from Voyager 1[/size][/url]

[b] Explanation: [/b] What are those spots on Jupiter? Largest and furthest, just right of center, is the [url=https://en.wikipedia.org/wiki/Great_Red_Spot]Great Red Spot[/url] -- a huge [url=https://apod.nasa.gov/apod/ap140518.html]storm system[/url] that has been raging on [url=https://solarsystem.nasa.gov/planets/Jupiter]Jupiter[/url] possibly since [url=https://en.wikipedia.org/wiki/Giovanni_Domenico_Cassini]Giovanni Cassini[/url]'s likely notation of it [url=https://en.wikipedia.org/wiki/1665]352 years ago[/url]. It is not yet known why this [url=https://www.nasa.gov/feature/goddard/jupiter-s-great-red-spot-a-swirling-mystery]Great Spot is red[/url]. The spot toward the lower left is one of Jupiter's largest moons: [url=https://en.wikipedia.org/wiki/Europa_(moon)]Europa[/url]. Images from [url=https://apod.nasa.gov/apod/ap031120.html]Voyager[/url] in 1979 bolster the modern hypothesis that Europa has an underground ocean and is therefore a [url=https://solarsystem.nasa.gov/planets/Europa]good place to look for extraterrestrial life[/url]. But what about the dark spot on the upper right? That is a shadow of another of Jupiter's large moons: [url=https://solarsystem.nasa.gov/planets/io]Io[/url]. Voyager 1 discovered [url=https://apod.nasa.gov/apod/ap140330.html]Io[/url] to be so volcanic that no [url=https://apod.nasa.gov/apod/ap141021.html]impact crater[/url]s could be found. Sixteen frames from [url=https://voyager.jpl.nasa.gov/]Voyager[/url] 1's flyby of Jupiter in 1979 were recently reprocessed and merged to create the [url=https://www.flickr.com/photos/alex-is-solaris/29919234526/in/dateposted-public/]featured image[/url]. Forty years ago today, [url=https://www.youtube.com/watch?v=xs-gJs1CKBY]Voyager[/url] 1 launched from Earth and started one of the [url=https://apod.nasa.gov/apod/ap170902.html]greatest explorations[/url] of the [url=https://apod.nasa.gov/apod/ap170211.html]Solar System[/url] ever.

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