TY  - JOUR
A1  - Mikucki, Jill Ann
A1  - Schuler, C. G.
A1  - Digel, Ilya
A1  - Kowalski, Julia
A1  - Tuttle, M. J.
A1  - Chua, Michelle
A1  - Davis, R.
A1  - Purcell, Alicia
A1  - Ghosh, D.
A1  - Francke, G.
A1  - Feldmann, M.
A1  - Espe, C.
A1  - Heinen, Dirk
A1  - Dachwald, Bernd
A1  - Clemens, Joachim
A1  - Lyons, W. B.
A1  - Tulaczyk, S.
T1  - Field-Based planetary protection operations for melt probes: validation of clean access into the blood falls, antarctica, englacial ecosystem
JF  - Astrobiology
N2  - Subglacial environments on Earth offer important analogs to Ocean World targets in our solar system. These unique microbial ecosystems remain understudied due to the challenges of access through thick glacial ice (tens to hundreds of meters). Additionally, sub-ice collections must be conducted in a clean manner to ensure sample integrity for downstream microbiological and geochemical analyses. We describe the field-based cleaning of a melt probe that was used to collect brine samples from within a glacier conduit at Blood Falls, Antarctica, for geomicrobiological studies. We used a thermoelectric melting probe called the IceMole that was designed to be minimally invasive in that the logistical requirements in support of drilling operations were small and the probe could be cleaned, even in a remote field setting, so as to minimize potential contamination. In our study, the exterior bioburden on the IceMole was reduced to levels measured in most clean rooms, and below that of the ice surrounding our sampling target. Potential microbial contaminants were identified during the cleaning process; however, very few were detected in the final englacial sample collected with the IceMole and were present in extremely low abundances (∼0.063% of 16S rRNA gene amplicon sequences). This cleaning protocol can help minimize contamination when working in remote field locations, support microbiological sampling of terrestrial subglacial environments using melting probes, and help inform planetary protection challenges for Ocean World analog mission concepts.
Y1  - 2023
U6  - https://doi.org/10.1089/ast.2021.0102
SN  - 1557-8070 (online)
SN  - 153-1074 (print)
VL  - 23
IS  - 11
SP  - 1165
EP  - 1178
PB  - Liebert
CY  - New York, NY
ER  - 
TY  - JOUR
A1  - German, Laura
A1  - Mikucki, Jill A.
A1  - Welch, Susan A.
A1  - Welch, Kathleen A.
A1  - Lutton, Anthony
A1  - Dachwald, Bernd
A1  - Kowalski, Julia
A1  - Heinen, Dirk
A1  - Feldmann, Marco
A1  - Francke, Gero
A1  - Espe, Clemens
A1  - Lyons, W. Berry
T1  - Validation of sampling antarctic subglacial hypersaline waters with an electrothermal ice melting probe (IceMole) for environmental analytical geochemistry
JF  - International Journal of Environmental Analytical Chemistry
N2  - Geochemical characterisation of hypersaline waters is difficult as high concentrations of salts hinder the analysis of constituents at low concentrations, such as trace metals, and the collection of samples for trace metal analysis in natural waters can be easily contaminated. This is particularly the case if samples are collected by non-conventional techniques such as those required for aquatic subglacial environments. In this paper we present the first analysis of a subglacial brine from Taylor Valley, (~ 78°S), Antarctica for the trace metals: Ba, Co, Mo, Rb, Sr, V, and U. Samples were collected englacially using an electrothermal melting probe called the IceMole. This probe uses differential heating of a copper head as well as the probe’s sidewalls and an ice screw at the melting head to move through glacier ice. Detailed blanks, meltwater, and subglacial brine samples were collected to evaluate the impact of the IceMole and the borehole pump, the melting and collection process, filtration, and storage on the geochemistry of the samples collected by this device. Comparisons between melt water profiles through the glacier ice and blank analysis, with published studies on ice geochemistry, suggest the potential for minor contributions of some species Rb, As, Co, Mn, Ni, NH4+, and NO2−+NO3− from the IceMole. The ability to conduct detailed chemical analyses of subglacial fluids collected with melting probes is critical for the future exploration of the hundreds of deep subglacial lakes in Antarctica.
Y1  - 2021
U6  - https://doi.org/10.1080/03067319.2019.1704750
SN  - 0306-7319
VL  - 101
IS  - 15
SP  - 2654
EP  - 2667
PB  - Taylor & Francis
CY  - London
ER  -