Venera Images, VENERA 13 fully calibrated image Options

[vikingmars]

Here is the Venera 13 fully calibrated image, produced from raw imaging 3-filters data (note the 3 horizons at left well discernible). It was published inside "L'Astronomie Magazine" of Societe Astronomique de France.
Enjoy !

Attached thumbnail(s)

 

[Toma B]

I heard about refraction in Venusian atmosphere...something like "you would have feeling that you are walkin at the bottom of crater with very steep walls even if you are on flat ground...don't remember quite well about that but, seeing the back of your own head????I HAVE NEVER HEARD SOMETHING LIKE THAT...please explain...

[helvick]

I heard about refraction in Venusian atmosphere...something like "you would have feeling that you are walkin at the bottom of crater with very steep walls even if you are on flat ground.

I seriously doubt that.

For starters refraction effects happen at interfaces or across density gradients. For the sort of effects described here you would need to have really bizarre density gradients all around you.

Things would probably look a bit different and heat shimmer effects might be more pronounced than on earth but they would be far less extreme than under water on earth for example.

The refractive index of CO2 at STP is 1.000449 (air is 1.000292). The refractive index of a gas changes (very approximately) with density according to (RIx=1+(RIstp-1)*(Dx/Dstp) so the RI of the venusian surface atmosphere is somewhere around 1.04041 (since the Venusian surface atmospheric density is approximately 90x the density of CO2 at STP).

Snells law gives us something to calculate what this would mean for a human in a spacesuit on the surface of Venus. Assuming we have an optically neutral window and we simplify the calculation down to an air (at stp) CO2 (at Venus surface) boundary.
Snell's law : RIi*Sin(Thetai)=RIr*Sin(Thetar)
Thetai = Incident beam angle and Thetar= Refracted beam angle
So Sin(Thetar)=1.000292*(sin(45deg)/1.04041
The refracted beam would be at 42.8deg. Noticable but not significant.
As a comparison for a water:air interface on earth the equivalent refracted beam would be at 32.9deg.

All in all it might be hard to play pool well on the surface of Venus but it certainly wouldn't create any bizarre visual effects.

[ljk4-1]

Don Dixon made some paintings of the alleged super refraction of Venus' atmosphere from the surface here:

http://www.cosmographica.com/gallery/portf...fraction%20.htm

http://www.cosmographica.com/gallery/portf...097-Inferno.htm

As a bonus, here is Dixon's rendition of what the Pioneer Venus Day Probe probably looked like as it sat on the planet's surface and radioed back to Earth for 67 minutes in 1978:

http://www.cosmographica.com/gallery/portf...enusLanding.htm