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Project Progress

Investigation 4 – Path to Flight Investigation Progress

The (Field Instrumentation and) Path to Flight investigation’s purpose is to enable in-situ measurements of organics and biological material with field instrumentation that have high potential for future flight instrumentation. The preceding three Investigations provide a variety of measurable goals used to modify or “tune” instrumentation that can be placed in the field. In addition the members of this Investigation provide new measurement capabilities that have been developed with the specific goal of life-detection. The instrument arsenal goes beyond the commercially available instrumentation and brings next generation imaging spectrometers, chromatographic, and sample extraction devices.

The Path to Flight investigation has three (3) primary Objectives, where Objectives 2 and 3 were the primary focus of these years efforts – given the reduced budget. Below are the objectives and a list of accomplished tasks.

OBJECTIVE1: Chemistry at Hydrothermal Vents: Characterization of mineral species in Laboratory Hydrothermal Vent experiments (related to Inv 1 efforts)

OBJECTIVE3: Ground Truth and Observability: Assessing Mojave Desert’s potential as a vadose zone ecosystem as an analogue for possible subsurface biospheres on Mars.

The following are some additional details associated to the accomplished tasks.

In an effort to tie together the in-situ instrumentation being developed as future flight instruments, we continued to employ Raman spectroscopy for analysis of hydrothermal vent chimneys generated in Inv 1 by Ph.D candidate Lauren Spencer and Co-I M. Russell. The intent was to better understand the mineralogy of these chimneys and specifically the effect of temperature and its effect on mineralogical species. The primary components being observed were greigite, mackinawite, and Fe(III) containing mackinawite – all of which catalyze the synthesis of organic compounds.

In addition to the detection, characterization, and quantification of these mineral features, the results have fed back into instrument development efforts. During the acquisition of the Raman spectra, it was evident that increased power densities normally used for Raman analysis resulted in thermal alteration of greigite or mackinawite to magnetite. Magnetite was not formed natively in the chimney at lower growth temperatures. Thus, for in-situ Raman instruments, inadvertent thermal alteration needs to be taken into consideration. The effects of Raman analysis on both mineral and organic compounds with solutions for in-situ Raman instruments is the subject of a paper currently in preparation (Bhartia et al., 2013, to be submitted.)

As a part of Investigation 4, we continued to make great progress in “LIFE” mission concept (see Tsou et al., 2012) investigation for Enceladus, a low-cost sample return mission to a body with high astrobiological potential (see Fig. 4-1).

The LIFE mission concept (Tsou et al., 2012) is envisioned in two parts: first, to orbit Saturn (in order to achieve lower sampling speeds, approaching 2 km/s, and thus enable a softer sample collection impact than Stardust, and to make possible multiple flybys of Enceladus); second, to sample Enceladus’ plume, the E ring of Saturn, and the Titan upper atmosphere. With new findings from these samples, NASA could provide detailed chemical and isotopic and, potentially, biological compositional context of the plume. Since the duration of the Enceladus plume is unpredictable, it is imperative that these samples are captured at the earliest flight opportunity. The LIFE concept offers science returns comparable to those of a Flagship mission but at the measurably lower sample return costs of a Discovery-class mission. We are preparing for a review in February 2014 to be a part of JPL’s DISCO’13 portfolio. We are collaborating with JAXA, Ariel Anbar of Arizona State University and one of the current NAI Principal Investigators and Chris McKay of NASA Ames.

As a part of Path to Flight investigation, Co-I Bhartia and colleagues assessed Mojave Desert’s potential as a vadose zone ecosystem as an analogue for possible subsurface biospheres on Mars. In their recent paper, they also describe several examples of Mars-like terrain found in the Mojave region and discuss ecological insights that might be gained by a thorough examination of the vadose zone in these specific terrains. Examples described include distributary fans (deltas, alluvial fans, etc.), paleosols overlain by basaltic lava flows, and evaporite deposits.

References:

Abbey, W., Salas, E., Bhartia, R. and Beegle, L. W. Astrobiology. July 2013, 13(7): 637-646. doi:10.1089/ast.2012.0948.

Bhartia, R., Hug, W.F., Fries, M., Reid, R., White, L., Salas E., “Sample Alteration and Solutions for Planetary Science” (2013) to be submitted, Astrobiology.

Tsou, P., Brownlee, D. E., McKay, C. P.; et al., LIFE: Life Investigation For Enceladus A Sample Return Mission Concept in Search for Evidence of Life , (2012) ASTROBIOLOGY, 12, Issue: 8 Pages: 730-742 DOI10.1089/ast.2011.0813