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)

 

[Guest_BruceMoomaw_*]

Yes, the first shots of Venus from Venera 9 and 10 turned out to be remarkable for their sheer ordinariness. Not only was there no super-refractive "swimming pool effect" (which had recently become a staple of SF stories about the planet; John Varley's first published story used it and was called "In the Bowl"), but even in those grainy photos it was clear that the horizon was fairly sharp and that the shadows even of small pebbles, despite the dense atmosphere, were quite sharp. In fact, the Soviets had equipped the two landers with floodlights on the assumption that the solar illumination might be too dim to see the surface otherwise! The much better photos from Venera 13 and 14, of course, confirmed all this even more dramatically (and also revealed that fiery orange sky, although I don't know whether that color was predicted in advance).

Scientists have, really, a pretty bad track record when it comes to predicting the optical qualities of surface photos. Remember how astonished everyone was when Viking 1's first black-and-white photos showed a light-colored sky (which later turned out to be pink) instead of the deep violet sky everyone had expected? They even predicted that deep violet sky again for Pathfinder, since there was less dust in the air at the time of its landing.

[ljk4-1]

Yes, the first shots of Venus from Venera 9 and 10 turned out to be remarkable for their sheer ordinariness.  Not only was there no super-refractive "swimming pool effect" (which had recently become a staple of SF stories about the planet; John Varley's first published story used it and was called "In the Bowl"), but even in those grainy photos it was clear that the horizon was fairly sharp and that the  shadows even of small pebbles, despite the dense atmosphere, were quite sharp.  In fact, the Soviets had equipped the two landers with floodlights on the assumption that the solar illumination might be too dim to see the surface otherwise!  The much better photos from Venera 13 and 14, of course, confirmed all this even more dramatically (and also revealed that fiery orange sky, although I don't know whether that color was predicted in advance). 

The big reason Soviet scientists thought Venus would be so dark at its surface is that the Venera 8 lander reported dim lighting conditions in 1972. Venera 8 did this with cadmium sulfide photoresistors (try to fit that phrase into your next dinner conversation), as it carried no cameras.

But what they did not seem to take into account was that the Sun was only 5 degrees above the horizon at the Venera 8 landing site when the readings were taken.

ftp://ftp.seds.org/pub/info/newsletters/e...93/jasa9303.txt

[ljk4-1]

Soviet Veneras and Mars: first entry probes trajectory reconstruction and science

Viktor Kerzhanovich, Jet Propulsion Laboratory,
Pasadena, CA, USA

Konstantin Pichkhadze, Lavochkin Association,
Moscow, Russia

Presented to International Workshop on Planetary
Probe Atmospheric Entry and Descent Trajectory
Analysis and Science

Lisbon, Portugal, 6-9 October 2003

http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/37338/1/03

Though most of the data and probe images are on the Veneras, there are some very nice diagrams of Mars 3 and 6 and data charts on the Martian atmosphere from Mars 6.

[tedstryk]

Great find! I had seen the Mars 6 stuff in an old 1977 paper he wrote in Icarus, but good to see that the dataset is being presented again. Regardless of overall value, it is the first in situ data (other than the mysterious Mars 3 blurb) from the Martian atmosphere and there are only five other decent profiles in existence - it would be a pitty for it to be totally forgotten.