Starship Asterisk*

[quote="Chris Peterson" post_id=314555 time=1624815197 user_id=117706]
If you're interested in actually analyzing the image based on wavelengths, about the only way to do it is to separate the three color planes completely, and present them as individual images, either in grayscale or a pseudocolor palette.
[/quote]

Or we can just dim and downplay the other channels.
Here I made the sunshine yellow (it is still in the right wavelength order in relation to red of the Suturn's thermal glow) and dimmed both the sunshine and the Suturn's thermal glow:
[img2]https://scontent.fhel4-1.fna.fbcdn.net/v/t1.6435-9/206181800_4048589975262083_3356475324552683728_n.jpg?_nc_cat=107&ccb=1-3&_nc_sid=dbeb18&_nc_eui2=AeH2BvWCsuxYj0TIgvTbltcoFE8Z4JGIq4YUTxngkYirhrgDHRa8_TkCaQXJvEg7jSmC-2XMGmXi6FSzWDWz7LWK&_nc_ohc=e_IMsP2kZoIAX91yV52&_nc_ht=scontent.fhel4-1.fna&oh=5139811bb4dd4cc54400e786f2c6b4dd&oe=60DF3BB1[/img2]

[quote=MarkBour post_id=314581 time=1624898007 user_id=141361]

Since the wavelengths are longer than one micrometer, I guess that if we had a seat on Cassini, human eyes would not have been able to see this aurora.
[/quote]
This aurora is [b][u]entirely in daylight[/u][/b].

Human eyes do not see daylight aurora.

Since the wavelengths are longer than one micrometer, I guess that if we had a seat on Cassini, human eyes would not have been able to see this aurora.

[quote=VictorBorun post_id=314554 time=1624814332 user_id=145500]
[url="https://photojournal.jpl.nasa.gov/catalog/PIA13402"]The legend[/url] specifies color mapping, and the colors are sorted in the natural order:
5 microns as [b][color=#FF0000]red[/color][/b] (Saturn's thermal emission from under the clouds)
3 and 4 microns as [b][color=#00FF00]green[/color][/b] (some hydrogen ions in aurora)
2 to 3 microns as [b][color=#0000FF]blue[/color][/b] (sunshine in near infrared)

Why then the picture looks spooky paranormal?
There is no greenish hues like yellow or cyan.
The only hue sectors filled are red-blue: the purple and the magenta.

To make the pic less ghostly we can re-arrange like this:
5 microns as [b][color=#FF0000]red[/color][/b] (Saturn's thermal emission from under the clouds)
2 to 3 microns as [b][color=#00FF00]green[/color][/b] (sunshine in near infrared)
3 and 4 microns as [b][color=#0000FF]blue[/color][/b] (some hydrogen ions in aurora)

Then aurora's hydrogen ions fluorescent out of the natural order, but we get the advantage to see as the red thermal glow from under the clouds merges naturally with the green of sunshine, making orange to yellow to lime:

[img2]https://scontent.fhel4-1.fna.fbcdn.net/v/t1.6435-9/205025204_4045828925538188_8675842778739213658_n.jpg?_nc_cat=110&ccb=1-3&_nc_sid=dbeb18&_nc_eui2=AeEv92LkX4-Ia4WzIL_Agkae44xer59VflfjjF6vn1V-VwuDwia0BxZuZy12XPX8rdjunJ6kr-9HyRtcg3ZvOYTd&_nc_ohc=vY2d_BZ5dv8AX_y1q5n&_nc_ht=scontent.fhel4-1.fna&oh=6e82a86b391c106cbbc583698a3ec605&oe=60DD1DA9[/img2]
[/quote]

If you're interested in actually analyzing the image based on wavelengths, about the only way to do it is to separate the three color planes completely, and present them as individual images, either in grayscale or a pseudocolor palette.

[url="https://photojournal.jpl.nasa.gov/catalog/PIA13402"]The legend[/url] specifies color mapping, and the colors are sorted in the natural order:
5 microns as [b][color=#FF0000]red[/color][/b] (Saturn's thermal emission from under the clouds)
3 and 4 microns as [b][color=#00FF00]green[/color][/b] (some hydrogen ions in aurora)
2 to 3 microns as [b][color=#0000FF]blue[/color][/b] (sunshine in near infrared)

Why then the picture looks spooky paranormal?
There is no greenish hues like yellow or cyan.
The only hue sectors filled are red-blue: the purple and the magenta.

To make the pic less ghostly we can re-arrange like this:
5 microns as [b][color=#FF0000]red[/color][/b] (Saturn's thermal emission from under the clouds)
2 to 3 microns as [b][color=#00FF00]green[/color][/b] (sunshine in near infrared)
3 and 4 microns as [b][color=#0000FF]blue[/color][/b] (some hydrogen ions in aurora)

Then aurora's hydrogen ions fluorescent out of the natural order, but we get the advantage to see as the red thermal glow from under the clouds merges naturally with the green of sunshine, making orange to yellow to lime:

[img2]https://scontent.fhel4-1.fna.fbcdn.net/v/t1.6435-9/205025204_4045828925538188_8675842778739213658_n.jpg?_nc_cat=110&ccb=1-3&_nc_sid=dbeb18&_nc_eui2=AeEv92LkX4-Ia4WzIL_Agkae44xer59VflfjjF6vn1V-VwuDwia0BxZuZy12XPX8rdjunJ6kr-9HyRtcg3ZvOYTd&_nc_ohc=vY2d_BZ5dv8AX_y1q5n&_nc_ht=scontent.fhel4-1.fna&oh=6e82a86b391c106cbbc583698a3ec605&oe=60DD1DA9[/img2]

[attachment=1]neonsaturnaurora_cassini_2560.jpg[/attachment]!


Reminds me of a party lantern! 8-)
It is beautiful


[attachment=0]BUCOEePIcAAht9h.jpg[/attachment]
Kitty even lazier then Magic! :lol2:

[quote=emc post_id=314543 time=1624793594 user_id=123932]
[youtube]https://youtu.be/ujmGiBl36f8[/youtube]
[/quote]

FYI, the youtube link parser only seems to understand the www.youtube.com and youtube.com domains, as in https://www.youtube.com/watch?v=ujmGiBl36f8 -


[youtube]https://www.youtube.com/watch?v=ujmGiBl36f8[/youtube]

[float=right][img3=actor Anthony Edwards]https://upload.wikimedia.org/wikipedia/commons/9/93/AnthonyEdwards.jpg[/img3][/float][quote="APOD Robot" post_id=314540 time=1624766726 user_id=128559]

[b] Explanation: [/b] What drives auroras on Saturn?. [/quote][quote=https://en.wikipedia.org/wiki/Oldsmobile_Aurora]

<<The Oldsmobile Aurora was a flagship sedan made by Oldsmobile from 1994 to 2003. It was a luxury sports sedan produced in two generations which, along with the two-door Buick Riviera, originated the Cadillac-derived G platform. Aurora was the official pace car of the 1997 and 2000 Indianapolis 500. At the beginning of the race in 1997, the pace car was driven by three-time Indy 500 winner Johnny Rutherford. At the beginning of the 2000 race, the pace car was driven by actor Anthony Edwards. These cars marked the ninth and tenth time an Oldsmobile had paced the Indianapolis 500 race.>>[/quote]

[url]https://youtu.be/ujmGiBl36f8[/url]

[youtube]https://www.youtube.com/watch?v=ujmGiBl36f8[/youtube]

[url=https://apod.nasa.gov/apod/ap210627.html] [img]https://apod.nasa.gov/apod/calendar/S_210627.jpg[/img] [size=150]The Dancing Auroras of Saturn[/size][/url]

[b] Explanation: [/b] What drives auroras on Saturn? To help find out, scientists have sorted through hundreds of infrared images of [url=https://solarsystem.nasa.gov/planets/saturn/overview/]Saturn[/url] taken by the [url=https://www.esa.int/Science_Exploration/Space_Science/Cassini-Huygens/Cassini_spacecraft]Cassini spacecraft[/url] for other purposes, trying to find enough aurora images to correlate changes and make [url=http://www.youtube.com/watch?v=fzwiTspxtrg]movies[/url]. Once made, some movies clearly show that [url=https://apod.nasa.gov/apod/ap081119.html]Saturnian auroras[/url] can change not only with the angle of the Sun, but also as the planet rotates. Furthermore, some [url=https://www.youtube.com/watch?v=7AmyfuJDMlY]auroral changes[/url] appear related to waves in Saturn's [url=https://en.wikipedia.org/wiki/Magnetosphere]magnetosphere[/url] likely caused by Saturn's moons. [url=https://photojournal.jpl.nasa.gov/catalog/PIA13402]Pictured here[/url], a false-colored image taken in 2007 shows Saturn in three bands of [url=https://science.nasa.gov/ems/07_infraredwaves]infrared[/url] light. The [url=https://apod.nasa.gov/apod/ap160313.html]rings reflect[/url] relatively blue sunlight, while the planet itself glows in [url=https://pbs.twimg.com/media/BUCOEePIcAAht9h.jpg]comparatively low energy[/url] red. A band of [url=https://apod.nasa.gov/apod/ap050222.html]southern aurora[/url] in visible in green. In has recently been [url=https://ui.adsabs.harvard.edu/abs/2020NatAs...4..872B/abstract]found[/url] that auroras [url=https://www.quantamagazine.org/cassini-data-solves-jupiter-and-saturns-energy-mystery-20210622/]heat Saturn's upper atmosphere[/url]. Understanding Saturn's auroras is a path toward a better understanding of [url=https://apod.nasa.gov/apod/ap100701.html]Earth's auroras[/url].


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