Description: We propose to build and critically test key subsystems of Life Analysis, Capture, and Retention on an Orbiting Saturn Spacecraft (LACROSS), an ultra-compact plume sample collection and analysis. LACROSS will conduct these analysis in-situ, directly on icy samples collected from the plume during fly-throughs. Thus, LACROSS addresses five of the six Technologies solicited by subtopic S4.06. LACROSS’ sample collection & management system utilizes an innovative architecture to a) collect particles using an angled-wall collector an b) analyze them in-situ, without the need for sample processing and concentrating. The collector funnels ice particles into plasmonic aerogel (Stardust heritage), where particles bury and slow down to a stop. The plasmonic aerogel enables ultra-sensitive (1 nM) SERS measurements of all particles that intersects the focus plane. LACROSS’ innovative approach to sample capture and analysis enables unprecedented in-flight sample collection and measurements of material freshly injected into space: in-situ chemical identification and quantitation of complex organic compounds, including pre-biotic compounds (e.g., amino acids); biomolecules (organic biomarkers such as proteins, lipids, and nucleic acid polymers); minerals; salts; volatiles. LACROSS will be a substantial technological leap with respect to existing or proposed sampling and/or analysis systems of Enceladus plume in the following key aspects: (1) it utilizes an innovative architecture to capture and transfer ice particles from plumes directly to a sensor that requires no moving parts, actuators, sample handling; (2) the multiplex integral-field SERS imaging approach features augmented science returns and reduced technical complexity relative to existing and proposed planetary Raman spectrometers; (3) LACROSS minimizes the resources and complexity required to capture and concentrate a sample and perform key investigations required to understand the habitability of Enceladus.

Benefits: LACROSS improves measurement capabilities of hypervelocity particles in Ocean Worlds plumes, comet comas, and upper planetary atmospheres. It simplifies the process of sample collection and analysis with a single, stream-lined instrument. LACROSS increases the sensitivity of planetary Raman spectroscopy to at least the nM range, which enables new and innovative scientific measurements that can replace complicated, risky sample collection and processing systems.

LACROSS may be adapted to measure the concentrations and concentration gradients of pollution/greenhouse gases, particularly those from the utilization of fossil fuels and aromatic volatile organic compounds in-situ, and in real time. LACROSS plasmonic aerogels could capture gases during atmospheric fly-throughs using unmanned aircraft (balloon, UAV) and analyze them on the fly. For example, mounted on a UAV, LACROSS can increase the efficiency of environmental monitoring.