Seismography Mission to Venus
Based upon a solicitation from NASA, we have designed and developped
a full specification for expanding human knowledge of Venus. This aims to be
mankind's return to the surface of the second planet from the Sun.
Top-Level Overview
Environmental Challenges
- Temperature
The average surface temperature of Venus is 462C. [1] This poses problems
for electronics, power generation, power storage, and general survivability.
- Pressure
The atmospheric pressues is 90 atm at the surface. [1] Previous probes such as the Soviet
Venera 5 and Venera 6 did not even reach the surface before being crushed. [2]
- Atmospheric Composition
Unlike Earth or Mars, the atmosphere on Venus is very hostile to most common substances.
The primary gases are carbon dioxide, sulfuric acid vapor, sulfur dioxide, and water vapor.
This is a corrosive mix that can also cause severe radio attenuation at X-band and higher. [3]
Mission Profile
- Goal
90 Day Seismograph Record of Venus, Secondary: Collect temperature, pressure, and wind data
- Transit Plan
Launch prior to closest approach to Venus and orbit until 50 days before
inferior conjunction
- Landing Plan
Use aerobraking and descent parachutes until 65km above the surface, then
proceed solely using aerobraking
- Environmental Hardening
- Solid titanium shell designed to survive 200 atmospheres of pressure
- Silicon Carbide electronics to survive 500C temperatures
- Sodium Sulfur batteries that only work at temperatures exceeding 250C
- Radioisotope thermoacoustic generators designed to produce 100W each at
ambient temperatures of 500C.
- High temperature ceramic gears that do not required lubrication to operate
the antenna rotator and ground drill
- Communications Suite
Pointable 3m dish antenna tranmitting at up to 250W to the Deep Space Network
at up to 25kbps using Turbo Codes to achieve a Bit Error Rate of 10^-6
[1] G. W. Hunter, G. E. Ponchak, R. W. Dyson, G. M. Beheim, M. C. Scardelletti, R. D. Meredith,
et al., "Development of a High Temperature Venus Seismometer and Extreme Environment Testing
Chamber," presented at the International Workshop on Instrumentation for Planetary Missions
(2012), Greenbelt, Maryland, 2012.
[2] (July 26, 2013). Venera. Available: https://en.wikipedia.org/wiki/Venera
[3] J. M. Jenkins, "Variations in the 13 cm Opacity below the Main Cloud Layer
in the Atmosphere of Venus Inferred from Pioneer-Venus Radio Occultation Studies 1978-1987,"
Doctor of Philosophy in Electrical Engineering, Electrical Engineering, Georgia Institute of Technology, 1992.