Have there been any official feasability studies into descending balloons into outer planetary atmospheres?

Question

The Vega program included a balloon floating in the Venus atmosphere. It seems no more balloons have been used on other planets since then. The Wikipedia article on Aerobots mentions JPL feasibility studies for Mars, Venus, Titan, and Jupiter, but does not cite any sources for Jupiter and the information there might be original research in the Wikipedia article.

Since then, have there been any official feasibility studies into descending balloons into the atmosphere of Jupiter or other outer planets? By official, I mean by or with funding from a major space agency or related institute, as opposed to semi-hobbyists doing calculations. What would be the biggest challenges, compared to the balloons that have been used on Venus?

Answer 1

I suspect there is nothing that really addresses your question, however, I do see Jupiter mentioned in these two although I don't think it is as carefully studied as are some other heavenly bodies like Venus and Titan:

1. [Cutts et al. 1995] J. A. Cutts, K. T. Nock, J. A. Jones, G. Rodriguez, and J. Balaram. Planetary exploration by robotic aerovehicles. Journal of Autonomous Robots, 2(4):261-282, 1995.
2. [DiCicco et al. 1995] A. G. DiCicco, K. T. Nock, and G. E. Powell. Balloon experiment at Venus (BEV). In JPL Planetary Aerobot Technology Development Program Papers presented at the AIAA 11th Lighter-Than-Air Technology Conference, Clearwater, May 1995. AIAA, American Institute of Aeronautics and Astronautics. (sorry, but I couldn't find a digital reference for this one)

Not sure how much funding these papers received though.

Disclaimer: I took these references from my thesis and it's been many years since I read them in their entirety. Jupiter is mentioned in the abstract of the first, however.

Answer 2

I think project ARCHIMEDES of the German Mars Society is somewhere within the grey zone between major agency and semi-hobbyists project. It is intended to deploy a balloon into the Mars' atmosphere. The project is backed by a number of public research institutes and the German space agency (DLR), while I believe that most of its funding is private. Regarding your question, they went significantly beyond just calculations and did actual high atmosphere tests with real hardware (at least two that I know of) using sounding rockets here on Earth (at Esrange near Kiruna in Sweden).

Further reading: http://arc.aiaa.org/doi/abs/10.2514/6.IAC-04-Q.P.02

The German Mars Society's site (in German, English translation is out-dated): http://archimedes.marssociety.de/