Development of Techniques Enabling Suborbital Small Object Capture Around Low Gravity Asteroids
This research addresses the high cost and complexity of asteroid sample return missions for space exploration agencies and scientists, offering a potentially more economical and simpler approach.
This paper proposes an alternative sample and return technique for low-gravity asteroids, leveraging the discovery of regolith particle ejections from Bennu. Instead of physical touchdown, nanospacecraft deployed from a mother-spacecraft would chase, collect, and return 1 cm particles that spend several hours in flight, reducing mission cost and complexity.
The exploration of small body asteroids provides direct access to the primitive building blocks of our solar system. Sample and return missions enable chemical and radioisotope studies which not only provide evidence for the formation of the solar system, but also a basic understanding of where resources might be found for future exploitation. The touch-down and sample techniques established by Hayabusa-2 and OSIRIS-REx accomplish this mission by physically touching down on the asteroid and collecting samples into a basket extended via a probe from the bottom of the spacecraft. This technique has been demonstrated to work, but contains a high cost in both mission operations as well as the size and complexity of the collection mechanism itself. This paper explores an alternative sample and return technique by exploiting the recent discovery of regolith particle ejections from Bennu. Particles ejected from the surface of Bennu are typically 1 cm in size and spend several hours in flight, suggesting the possibility that nanospacecraft deployed from the mother-spacecraft could chase down, collect and return with the sample with minimal sensor and delta-V capability. Key aspects of this mission are developed to reduce risk, and an overall mission concept is developed to establish plausibility.