RAMS: RAman-Mass Spectrometer for planetary exploration

RAMS will enable comprehensive analysis of the surface chemistry of astrobiologically-relevant planetary bodies by characterizing organic and inorganic inventories as well as their spatial distribution in rocky or icy planetary sample materials via fine spatial resolution (geo)chemical imaging enabled by a combination of laser desorption ionization imaging mass spectrometry and Raman microspectroscopy. The unprecedented level of integrated analytical capabilities promises to shed light on the provenance and distribution of organic as well as inorganic material in planetary surfaces samples and inform on dominant chemical processes leading to their formation and evolution during planetary body evolution.

Science Goals and Objectives. To achieve their main objectives, future landed missions to solar system destinations of high astrobiological/astrochemical interest will require science instrumentation capable of accomplishing comprehensive and highly sensitive in situ analyses of surface samples in order to (i) assess habitability, as in the case of Ocean Worlds, or (ii) infer the role of small airless bodies in seeding organic material on early Earth and other solar system bodies, as in the case of comets and asteroids. RAMS enables such a detailed in situ characterization of the planetary surface samples through acquisition of spatially resolved maps of (i) overall organic content, including macromolecular carbon reservoirs, (ii) astrobiologically-relevant molecules, such as nucleobases, amino acids, amines and carboxylic acids, as well as (iii) mineral phases in the delivered samples. The combination of trace level sensitivity and specificity to organic species and ability to reveal organic-inorganic material associations provides an important dataset to understand the provenance of the organic material and help inform on the evolution of the sampled planetary surface.

Methodology. RAMS is a highly capable analytical instrument that offers the complementary strengths of laser desorption/ionization mass spectrometry (LDMS) and Raman spectroscopy (RS) in a streamlined, hybrid instrument package expected to offer size, weight and power (SWaP) savings over two separate instruments and thus conform to the resource constraints of future Discovery- and New Frontiers-class missions. Building on our team’s interdisciplinary experience in miniaturized instrument technology development, we will integrate a fiber-coupled dual-wavelength Raman spectrograph with a laser desorption/ionization mass spectrometer utilizing a raster-scanning capable, narrow spectral bandwidth, two-wavelength solid state laser source compatible with, both, LDMS and RS, to enable acquisition of co-localized information on mineral (mainly via RS) and organic (mainly via LDMS) fractions in planetary surface samples.

Relevance. RAMS is a hybrid LDMS/RS instrument that will provide comprehensive sample analysis capabilities transcending those of either technique alone by providing organic molecular and mineralogical composition maps of the sample on a sub-100 micron spatial scale, thus directly responding to the PICASSO program objective to “…develop new proof-of-concept instruments that enable new science by significantly improving instrument measurement capabilities for planetary science missions”. The proposed work draws significantly from our team’s expertise in space-flight laser, spectrograph, and prototype LDMS developments, as well as our in-depth experience in LDMS and RS analytical techniques. The outcome of the proposed work will be a RAMS breadboard instrument prototype capable of sensitive detection and identification of molecular organics via LDMS and detailed characterization of mineralogical context via RS to provide a thorough understanding of the chemistry of the planetary surface samples. More »