Editing Aerobot (section)

=== Venus ===
JPL has also pursued similar studies on Venus aerobots. A Venus Aerobot Technology Experiment (VEBTEX) has been considered as a technology validation experiment, but the focus appears to have been more on full operational missions. One mission concept, the Venus Aerobot Multisonde (VAMS), envisions an aerobot operating at altitudes above {{convert|50|km|mi}} that would drop surface probes, or "sondes", onto specific surface targets. The balloon would then relay information from the sondes directly to Earth, and would also collect planetary magnetic field data and other information. VAMS would require no fundamentally new technology, and may be appropriate for a NASA low-cost [[Discovery Program|Discovery planetary science mission]].
 
Significant work has been performed on a more ambitious concept, the Venus Geoscience Aerobot (VGA). Designs for the VGA envision a relatively large reversible-fluid balloon, filled with helium and water, that could descend to the surface of Venus to sample surface sites, and then rise again to high altitudes and cool off.

Developing an aerobot that can withstand the high pressures and temperatures (up to 480 degrees Celsius, or almost 900 degrees Fahrenheit) on the surface of Venus, as well as passage through sulfuric acid clouds, will require new technologies. As of 2002, VGA was not expected to be ready until late in the following decade. Prototype balloon envelopes have been fabricated from [[polybenzoxazole]], a polymer that exhibits high strength, resistance to heat, and low leakage for light gases. A gold coating is applied to allow the polymer film to resist corrosion from acid clouds.

Work has also been done on a VGA gondola weighing about {{convert|30|kg|lb}}. In this design, most instruments are contained in a spherical pressure vessel with an outer shell of [[titanium]] and an inner shell of [[stainless steel]]. The vessel contains a solid-state camera and other instruments, as well as communications and flight control systems. The vessel is designed to tolerate pressures of up to a hundred atmospheres and maintain internal temperatures below {{convert|30|C|F}} even on the surface of Venus. The vessel is set at the bottom of a hexagonal "basket" of solar panels that in turn provide tether connections to the balloon system above, and is surrounded by a ring of pipes acting as a heat exchanger. An [[S-band]] communications antenna is mounted on the rim of the basket, and a radar antenna for surface studies extends out of the vessel on a mast.

The [[Venus Atmospheric Maneuverable Platform]] (VAMP) is a mission concept by the aerospace companies [[Northrop Grumman]] and [[LGarde]] for a powered, long endurance, semi-buoyant inflatable aircraft that would explore the upper atmosphere of Venus for [[biosignature]]s<ref>[http://earthsky.org/space/new-study-ponders-possible-life-adrift-in-venus-clouds Astronomers ponder possible life adrift in Venus' clouds]. Deborah Byrd, ''Earth & Sky''. 31 March 2018.</ref><ref>[https://www.inquisitr.com/4850106/scientists-explore-the-possibility-of-life-hidden-inside-the-clouds-of-venus/ Scientists Explore The Possibility Of Life Hidden Inside The Clouds Of Venus]. Kritine Moore, ''The Inquisitr''. 1 April 2018.</ref> as well as perform atmospheric measurements.<ref name='Devitt 2018'>[https://www.sciencedaily.com/releases/2018/03/180330171302.htm Is there life adrift in the clouds of Venus?]. Terry Devitt, ''Science Daily''. 30 March 2018.</ref>

In April 2021 it was reported that NASA allocated work to design and test robotic balloons for future [[Observations and explorations of Venus|exploration of Venus]].<ref>{{cite news |title=Robotic Balloons To Explore Venus? This Northwest Company Is Working On It |url=https://www.nwpb.org/2021/04/10/robotic-balloons-to-explore-venus-this-northwest-company-is-working-on-it/ |access-date=9 May 2021 |work=Northwest Public Broadcasting |date=11 April 2021}}</ref>