Several worlds in our solar system are thought to hold oceans of liquid water beneath their frozen surfaces. These subsurface ice and ocean environments are promising targets in the search for life beyond Earth, but they also present significant new technical challenges to planetary exploration. With a focus on Jupiter’s moon Europa, here we (1) identify major benefits and challenges to subsurface ocean world science, (2) provide a multidisciplinary survey of relevant sample handling and life detection technologies, and (3) integrate those perspectives into the Subsurface Science and Search for Life in Ocean Worlds (SSSLOW) concept payload. We discuss scientific goals across three complementary categories: (1) search for life, (2) assess habitability, and (3) investigate geological processes. Major mission challenges considered include submerged operation in high-pressure environments, the need to sample fluids with a range of possible chemical conditions, and detection of biosignatures at low concentrations. The SSSLOW addresses these issues by tightly integrated instrumentation and sample handling systems to enable sequential, complementary measurements while prioritizing preservation of sample context. In this work, we leverage techniques and technologies across several fields to demonstrate a path toward future subsurface exploration and life detection in ice and ocean worlds.

The rise of antibiotic resistance in a population involves two distinct processes: the origin of resistance and its spread.  Here we study the contribution of both processes to the increase in daptomycin resistance in Enterococcus faecium in a hospital system. This case-control genomic study includes whole-genome sequencing of 82 isolates obtained from 24 case patients with clinically determined daptomycin-resistance and 24 controls. Among the case patients, the first isolate was resistant in 15 patients (R patients) while in the remaining nine the first isolate was susceptible but was followed by one or more resistant isolates (SR patients). Mutations in a set of candidate daptomycin resistance genes were compared within and between all patients. Additionally, among closely related isolates, mutations were identified across the entire assembled genome. Daptomycin resistance evolved separately multiple times and there was no phylogenetic clustering of the R or the SR groups. Six of the nine SR pairs gained mutations in previously identified candidate loci for daptomycin resistance, with the major cardiolipin synthase (clsA) being mutated most frequently. The hospital-wide increases in daptomycin resistance in E. faecium was the result of recurrent evolution taking multiple evolutionary pathways and occasional transmission of resistant isolates between patients.

High-altitude balloons (HABs) present a valuable and cost-effective tool for educators and students to access the conditions that are analogous to space and extraterrestrial environments in the Earth’s upper atmosphere. Historically, HABs have been used for meteorological measurements, observation, sampling of aerosols, and exposure of samples to upper atmosphere environments. The Earth’s stratosphere allows researchers access to a unique combination of wideband solar radiation, extreme cold, rarefied air, low humidity, and acute ionizing radiation—conditions that are relevant to space biology research. Here, we describe a reproducible payload for a HAB mission that can be constructed, launched, and retrieved for about $3,000. This general standard operating procedure can be used by educators, community scientists, and research teams working with limited resources.

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MOTIVATIONAn autonomy revolu on is underway on Earth, and autonomous vehicles are being employed in space to enable diverse missions including on Mars 1 , Titan 2 , and other Ocean Worlds. Miniaturized sensors, hardware, novel materials and structures, addi ve manufacturing, machine learning, and other advancements are being integrated to enable capabili es once firmly in the realm of science fic on. Machine learning is being applied to predic ve maintenance, trajectory op miza on, genera ve designs, improved quality control, training, robot percep on, autonomous decision making, and other areas.Autonomous technology development has valuable applica ons for missions to a diverse array of planetary environments 3 , and has been iden fied as an area of key technology investment for the next genera on of interplanetary missions 4 . Despite substan al progress, the challenges of planetary explora on, including seeking and suppor ng life beyond Earth, require new capabili es. These include, but are not limited to, accessing surface and subsurface regions unreachable by large rovers or humans, and opera ng with extreme efficiency and for sustained periods without communica on. Addressing these complex challenges will require broad and persistent efforts, enabling opportuni es to: