Question Enceladus

Nov 25, 2019
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If a probe were sent to land on Enceladus and it turned its back to the sun and pointed its camera towards a water vent, would we potentially see a rainbow?
If yes - would it have the same colour characteristics and curvature as those observed on earth?
 
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MMohammed

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Oct 10, 2019
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Sheesh, that's a great question. My guess is it would depend on the shape of the water droplets, perhaps?
 
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Sheesh, that's a great question. My guess is it would depend on the shape of the water droplets, perhaps?
yeah, thinking about it I don't really know enough about rainbows on earth to know where the differences might be.
I was wondering if there was a difference in the refractive index of the atmosphere... if that's a thing! Or even whether you need an atmosphere? If you took a water vapour aerosol can to the moon and did the same - would you get a rainbow?
Thanks for answering..
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
Is this getting close:
"Another Saturn's moon, Enceladus, is a very active world with water ice plumes dashing through the cracks in its icy surface. Water ice crystals are not the same as water droplets, but combined with the sunlight they are known to produce a family of optical phenomena here on Earth called halos. "
 
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Is this getting close:
"Another Saturn's moon, Enceladus, is a very active world with water ice plumes dashing through the cracks in its icy surface. Water ice crystals are not the same as water droplets, but combined with the sunlight they are known to produce a family of optical phenomena here on Earth called halos. "

Perfect.... many thanks for this!
 
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A rainbow needs the water droplets to be liquid. I suspect (but do not know) the water turns to ice very quickly but perhaps can exist for a short time after ejection as liquid (droplets) and maybe a bit more time as supercooled liquid - maybe long enough to make a rainbow if viewed from the right place. But it is effectively vacuum there and droplets will be trying to boil - so perhaps won't stay clear enough for light to travel through and refract for more than a brief moment?
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
" For a droplet freezing on PMMA, the freezing time (τf approximately 41 s) is much larger than the vapor diffusion time (τD approximately 0.1 s)."

And if you check:
Frost halos from supercooled water droplets
Stefan Jung, Manish K. Tiwari, and Dimos Poulikakos
you will find a pretty little droplet with a halo.

Frost halos from supercooled water droplets. - NCBI
www.ncbi.nlm.nih.gov › pubmed
by S Jung - ‎2012
where you will find these pictures:


by S Jung - ‎2012
 
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" For a droplet freezing on PMMA, the freezing time (τf approximately 41 s) is much larger than the vapor diffusion time (τD approximately 0.1 s)."

And if you check:
Frost halos from supercooled water droplets
Stefan Jung, Manish K. Tiwari, and Dimos Poulikakos
you will find a pretty little droplet with a halo.

Frost halos from supercooled water droplets. - NCBI
www.ncbi.nlm.nih.gov › pubmed
by S Jung - ‎2012
where you will find these pictures:


by S Jung - ‎2012

Perfect, thanks for the research Cat..
Andrew
 
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" For a droplet freezing on PMMA, the freezing time (τf approximately 41 s) is much larger than the vapor diffusion time (τD approximately 0.1 s)."

And if you check:
Frost halos from supercooled water droplets
Stefan Jung, Manish K. Tiwari, and Dimos Poulikakos
you will find a pretty little droplet with a halo.

Frost halos from supercooled water droplets. - NCBI
www.ncbi.nlm.nih.gov › pubmed
by S Jung - ‎2012
where you will find these pictures:


by S Jung - ‎2012
Those are ice crystal halos that would inhibit light forming rainbows as they form - "a condensation halo around the droplet, which crystallizes and drastically affects the surface behavior".
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
Just came across this:
https://www.atoptics.co.uk/halosim.htm

"Ice halo displays range from the familiar circle around the sun or moon to rare and prized events when the whole sky is webbed by intricate arcs.
Tiny ice crystals in the atmosphere create halos by refracting and reflecting light.
Halos bestow a delicate beauty to the skies and tell us about the crystals inhabiting the clouds.
Find out how halos are formed, when and where to see them in the skies.

Create your own halo displays by downloading the full colour simulator program, HaloSim."

I haven't tried it, but I thought the bottom line might interest you.
 
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Just came across this:
https://www.atoptics.co.uk/halosim.htm

"Ice halo displays range from the familiar circle around the sun or moon to rare and prized events when the whole sky is webbed by intricate arcs.
Tiny ice crystals in the atmosphere create halos by refracting and reflecting light.
Halos bestow a delicate beauty to the skies and tell us about the crystals inhabiting the clouds.
Find out how halos are formed, when and where to see them in the skies.

Create your own halo displays by downloading the full colour simulator program, HaloSim."

I haven't tried it, but I thought the bottom line might interest you.
Thanks for this Cat, have tried it out and I must admit that I had some difficulties understanding the parameter values.
This is me and not the program! more study required(!) Thanks again
Andrew
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
https://wonderdome.co.uk/space-rainbows/

QUOTE
Another Saturn’s moon, Enceladus, is a very active world with water ice plumes dashing through the cracks in its icy surface. Water ice crystals are not the same as water droplets, but combined with the sunlight they are known to produce a family of optical phenomena here on Earth called halos. Would anyone like to travel 7 years to check if there are beautiful icy rainbows on Enceladus?

How about Jupiter’s moon Europa? We sure do remember the recent NASA reports about the discovery of the water plumes on the Jovian moon? Maybe the upcoming NASA Europa Clipper mission will return some beautiful photographs of Europa’s rainbows and halos! We cannot wait!
QUOTE

Is this real??
 
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https://wonderdome.co.uk/space-rainbows/

QUOTE
Another Saturn’s moon, Enceladus, is a very active world with water ice plumes dashing through the cracks in its icy surface. Water ice crystals are not the same as water droplets, but combined with the sunlight they are known to produce a family of optical phenomena here on Earth called halos. Would anyone like to travel 7 years to check if there are beautiful icy rainbows on Enceladus?

How about Jupiter’s moon Europa? We sure do remember the recent NASA reports about the discovery of the water plumes on the Jovian moon? Maybe the upcoming NASA Europa Clipper mission will return some beautiful photographs of Europa’s rainbows and halos! We cannot wait!
QUOTE

Is this real??
blimey, thanks cat - wonder whether they read my question!
 
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Jun 17, 2020
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In fact a rainbow/prism effect will occur anywhere is space where light passes through a water droplet or ice particle, as the white light will be spilt into its component colours
Dave
 
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In fact a rainbow/prism effect will occur anywhere is space where light passes through a water droplet or ice particle, as the white light will be spilt into its component colours
Dave
Cheers Dave... would the curvature of a rainbow appear the same as one on earth?
 
So, on Titan, apparently it rains, but, it's methane rain. Sometimes, if the haze isn't so thick, perhaps there's a rainbow there, too. It would be interesting to see what the spectrum looks like.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
"Titan's atmosphere is "humid," meaning rich in methane. ... On Titan, rainbows would form when sunlight bounces in and out of methane droplets, which, like water droplets, are transparent."

Rainbows on Titan | Science Mission Directorate


Are there rainbows on other planets? - BBC Science Focus ...
https://www.sciencefocus.com › Space

On Saturn's moon Titan, for example, the atmosphere is rich in liquid methane droplets that almost certainly form rain. Titan's atmosphere is extremely hazy, ...


Do Other Planets Have Rainbows? | Times Knowledge India
https://www.timesknowledge.in › science › space › do-...

3 Jun 2019 — Titan's atmosphere is very hazy, signaling that direct sunlight is probably uncommon, but there is a small chance that methane rainbows can ...


Cat :)
 
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If a probe were sent to land on Enceladus and it turned its back to the sun and pointed its camera towards a water vent, would we potentially see a rainbow?
If yes - would it have the same colour characteristics and curvature as those observed on earth?
I don't see how it's possible. No matter how warm the water would be inside enceladus, it's so cold there that it would instantly freeze. However the salt that's in the water, could act like an antifreeze, but I seriously don't think it would amount to much protection from the bitter cold.