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arXiv · 2507.11581

SAMPLE -- Stratospheric Altitude Microbiology Probe for Life Existence -- A Method of Collection of Stratospheric Samples Using Balloon-Borne Payload System

Margarita Safonova·Bharat Chandra P·Binukumar G. Nair·Akshay Datey·Dipshikha Chakravortty·Ajin Prakash·Mahesh Babu·Shubham Ghatul·Shubhangi Jain·Rekhesh Mohan·Jayant Murthy
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Abstract

The Earth possesses many environmental extremes that mimic conditions on extraterrestrial worlds. The stratosphere at 30-40 km altitude closely resembles the surface of Mars in terms of pressure, temperature, and radiation levels (UV, proton, and Galactic cosmic rays). While microbial life in the troposphere is well documented, the true upper limit of Earth's biosphere remains unclear. The stratosphere offers a promising environment to explore microbial survival in such extreme conditions. Despite its significance to astrobiology, this region remains largely unexplored due to difficulties in access and avoiding contamination. To address this, we have developed SAMPLE (Stratospheric Altitude Microbiology Probe for Life Existence), a balloon-borne payload designed to collect dust samples from the stratosphere and return them in conditions suitable for lab analysis. The entire system is novel and designed in-house, with weight- and stress-optimized components. The main payload includes three pre-sterilized sampling trays and a controller that determines altitude and governs tray operation. One tray will remain closed during flight (airborne control) and another on the ground (cleanroom control) to monitor contamination. Additional systems include environmental sensors, GPS trackers, cameras, and a Flight Termination Unit (FTU) to end the mission once sampling is complete. A parachute ensures the safe recovery of the payload. Upon retrieving the payload, the sampling trays (including controls) will be sent to a suitable laboratory where the samples will be examined for the presence and nature of collected material.

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Margarita Safonova, Bharat Chandra P, Binukumar G. Nair, Akshay Datey, Dipshikha Chakravortty, Ajin Prakash, Mahesh Babu, Shubham Ghatul, Shubhangi Jain, Rekhesh Mohan, Jayant Murthy. 2025-10-27. SAMPLE -- Stratospheric Altitude Microbiology Probe for Life Existence -- A Method of Collection of Stratospheric Samples Using Balloon-Borne Payload System. https://doi.org/10.15406/aaoaj.2025.09.00233

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