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Update: Newly published paper in Nature Geoscience Atmospheric mountain wave generation on Venus and its influence on the solid planet’s rotation rate has open-access links in Science News, Motherboard, and Science.

There is a stationary gravity wave in Venus's very dense atmosphere. It is intermittent, but has been detected several times. See the NYTimes article Venus Smiled, With a Mysterious Wave Across Its Atmosphere for a discussion of recent observations by JAXA. See Akatsuki and Happy Birthday, Akatsuki!, celebrating it's first Venusian year at Venus.

Considering the extremely high density of the atmosphere near the surface, would it be possible for a suitably shaped spacecraft to "surf" or somehow remain aloft in this wave without propulsion, or even use it to rise high in the atmosphere, taking vertical data (e.g. composition, temperature, radar surface imagery and doppler profiling) and then gently return to the surface?

enter image description here

above: "A sequence of images showing the stationary nature of the bow-shape wave above Venus when it was observed in December 2015. Planet-C" from NYTimes. credit: Planet-C/JAXA

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above: "An illustration of how gravity waves travel up mountains and into Venus’s atmosphere. Credit ESA" From How Mountains Obscured by Venus’s Clouds Reveal Themselves.

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    $\begingroup$ You could use a balloon if you could make it out of a material that could withstand the heat and the chemical reactions (e.g., I recall Venus having sulfuric acid in its atmosphere). $\endgroup$
    – honeste_vivere
    Commented Jan 30, 2017 at 14:25
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    $\begingroup$ @honeste_vivere I'm asking about a craft using this articular atmospheric phenomenon to rise to high altitude without using propulsion. e.g. a glider. A balloon can generate lift on its own \on Venus anytime, anywhere, and so wouldn't be related to this question, would it? $\endgroup$
    – uhoh
    Commented Jan 30, 2017 at 17:28
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    $\begingroup$ Ah yes, that is slightly different. In that case, they are still relying upon a pressure gradient but instead of "pushing air down" there is an unbalanced dynamic pressure due to the rising air. Okay, I think I am starting to see what your are thinking about... $\endgroup$
    – honeste_vivere
    Commented Jan 30, 2017 at 18:48
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    $\begingroup$ O.k. , i'll think about it. Gliders could be very succesful within the polar vortices of Venus. en.wikipedia.org/wiki/Polar_vortex $\endgroup$
    – Cornelis
    Commented Oct 13, 2018 at 12:53
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    $\begingroup$ @Cornelisinspace If you think you've found a contradiction, why not ask about it in a new question? That will allow other users to look into it as well. This is a specific question and will have a clear answer, so I think you can ask it in a way that's both on-topic and not too broad. $\endgroup$
    – uhoh
    Commented Nov 20, 2019 at 22:37

1 Answer 1

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The density of carbon dioxide on Venus varies from about 67 kg/m3 at the surface to about 52 kg/m3 at a height of about 5 km, calculated with this software tool

Average wind speed Venus

Image from Solar Powered Flight on Venus

According to the graph above and Appendix A from the article the wind speed on Venus varies from 0.6 m/sec at the surface to 1.2 m/sec at a height of 5 km.

The dynamic force at the surface on 1 square meter would be: 1/2 x 67 kg/m$^3$ x (0.6$)^2$ m$^2$/sec$^2$ x 1 m$^2$ = 12.06 kgm/sec$^2$.

The dynamic force at a height of 5 km on 1 m$^2$ would be: 1/2 x 52 kg/m$^3$ x (1.2)$^2$ m$^2$/sec$^2$ x 1 m$^2$ = 37.44 kgm/sec$^2$.

Aphrodite Terra is the highland region near the equator that causes the wave in the atmosphere and looking at the image of its topography its height will be 5-7 km.
So we could assume that at a height of 5 km near the border of the highland the horizontal wind of 1.2 km/sec would be forced to go vertical, so the vertical dynamic force there would be about 37 kgm/sec$^2$.

So with a surface gravity of Venus being 8.87 m/sec$^2$ and a horizontal surface area of 1 m$^2$ for the spacecraft it probably could have a mass of a few kg to stay above the highland region !

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  • $\begingroup$ Thanks for the excellent analysis! I can't find a suitable humorous image to go along with "Surf's up!" right now nor 1950's movie clip in YouTube, but I'll keep an eye out for one. $\endgroup$
    – uhoh
    Commented Oct 12, 2018 at 11:07
  • $\begingroup$ @uhoh It could be that my analysis is much to simple. $\endgroup$
    – Cornelis
    Commented Oct 12, 2018 at 11:36
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    $\begingroup$ @uhoh O.K, thank you for being informed about this interesting " wave ". $\endgroup$
    – Cornelis
    Commented Oct 12, 2018 at 17:49
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    $\begingroup$ Oh, I see what you mean, thanks for the update. Well if a suitable suit could be manufactured then one of these surfing dogs might be able to give it a try :-) $\endgroup$
    – uhoh
    Commented Apr 3, 2020 at 22:30
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    $\begingroup$ @uhoh Great video, and nothing against dogs, but concerning the exploration of Venus i think even today's robots would be better in balancing the board. :-) $\endgroup$
    – Cornelis
    Commented Apr 4, 2020 at 9:01

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