In 2004, we ran our first curated virtual space mission for Georgia Tech’s graduate-level ECE 6390, Satellite Communications. The project was entitled “Deep-Penetrating Neptune Probes” and involved a hypothetical planetary NASA mission to the gas giant Neptune to study the atmospheric composition of the gas giant. Originally suggested by Prof. Steffes (like many of the curated virtual space missions that followed), the project page archive can be found here.
Due to their extreme distances from earth, we have sent relatively few probes to the outer gas giants of our solar system (Jupiter, Saturn, Uranus, and Neptune). NASA is proposing an ambitious mission to Neptune within 10 years that will insert 3 probes into the atmosphere, at lattitudes of 0◦, +45◦, and −45◦. Due to the size and density of the atmosphere, the probes will take 50 hours to descend to a pressure of 1000 bar. During this time, the probes’ scientific instruments will be measuring and recording data and sending it back to earth (presumably through a relay satellite) at a rate of 8 kbps each.
You have been contracted to design the satellite system that collects probe data and sends it real- time back to the earth. Not only is Neptune extremely distant from the earth, but the probes must report back through miles and miles of the planet’s dense, exotic atmosphere of hydrogen, helium, and methane. You may assume that earth stations in NASA’s Deep Space Network (DSN) are available for you to transmit and receive data. Each DSN site contains a 34m diameter dish antenna with Tsys = 20K and aperture efficiency of 0.94. The DSN transmitters are capable of transmitting up to 500,000 watts and at least one station is always visible to Neptune.