Letter | Much to Learn in Mars Sample Return
The Mars sample return (MSR) mission being investigated by NASA’s Jet Propulsion Laboratory is a fundable module that provides a golden opportunity to accomplish several crucial goals of the piloted mission to Mars within one compact mission.
The mission development time is consistent with readying the nuclear rocket for MSR propulsion. This would validate nuclear propulsion for the piloted mission to Mars and is a perfect opportunity to incorporate biological samples in the MSR mission, which would expose selected flora and fauna to the Mars journey environment and provide a base for the piloted mission requirements.
The overriding challenges of MSR are landing, scooping up the sample, transferring to the ascent vehicle, reaching Mars orbit and handing off the sample to the orbiting Earth return vehicle, then returning to Earth orbit and to Earth’s surface. This architecture is fraught with risk, but some can be mitigated.
Upon reaching Mars, an economical method to enter Mars orbit is via aerodynamic capture, whereby repeated “dipping” into the atmosphere produces drag to lower the apogee. Mars is known to be subject to global dust storms, and if the aero-capture process is then occurring, it is fairly simple to scoop up samples of the dust-laden upper atmosphere and return that to Earth, thereby avoiding the landing, sampling and return to Mars orbit (which still would need to be addressed in readiness for the piloted Mars mission).
All in all, MSR is presenting an outstanding opportunity to reduce risk to the piloted Mars mission.
Ernest Y. Robinson,
Retired nuclear engineer, Aerospace Corp.
Altadena , Calif.