Planetary Analogue Field Studies Network (PAFS-net)

The principal goals of PAFS-net are to engage the planetary science community in a holistic approach to in-situ exploration and establish a knowledgebase for the benefit of future exploration of the Solar System. To achieve these objectives, a coordinated programme of thematic studies involving planetary analogue materials (GSPARC) and a wide variety of in-situ measurement techniques is underway. Over time, results from the individual studies will accumulate into a shared archive of inter-related experimental data. These data together with the collective experience acquired by the PAFS-net membership will provide an invaluable contribution to future planetary exploration.

A broad range of disciplines are represented within PAFS-net including geology, astrobiology, geophysics, rock and soil mechanics, instrument development, payload engineering and robotics (including AI). Similarly, the range of appropriate in-situ analytical techniques is equally broad and includes spectroscopy (X-ray, Mössbauer, Raman, LIBS etc), imaging (micro, macro, remote, spectral), sample preparation and acquisition, and molecular analysis. Where possible, PAFS-net utilises space qualified or prototype instruments with which to conduct experiments. In the absence of either, PAFS-net studies make use of available laboratory equipment (especially portable kit) and adopt an emulation strategy.

PAFS-net is not necessarily confined to any planet, mission, payload or instrument as many of the investigations share common goals. By combining individual “discipline”, “analogue” or “sample” focused studies, the practical challenges of in-situ field measurement can be addressed from the planetary point of view. Obvious outcomes could include exploitation of instrument synergies, better understanding of instrument inter-dependencies and guidance on operational strategies.

To comply with the PAFS-net philosophy, the following rules must apply (irrespective of whether experiments are performed in the laboratory or in the field): -

• Experiments are controlled and constrained within the planetary context
• Samples are field representative
• Measurements are in-situ

All PAFS-net experiments are configured in order to emulate the planetary field scenario. Only if instrumentation is particularly sensitive to environmental parameters (pressure, temperature, atmospheric composition etc) should experiments be performed in dedicated chambers. For the most part however experiments are performed in the open lab or in the field. Obviously, emulating the “real world” naturally introduces complexity and many variables have to be considered, even within a single specimen. This is particularly relevant to analytical techniques but can also influence experiments with sampling devices as well. The hierarchical format philosophy of GSPARC therefore helps to provide a transition between calibration type measurements (i.e. homogenised powders) and application type measurements (i.e. heterogeneous, fresh, weathered and altered hand specimens etc). This is sometimes called characterisation and is a recommended procedure to adopt as part of, or a precursor to, any study programme (assuming such data are not in the knowledgebase already).

PAFS-net relies on the following assets to function: -

• A group of highly respected planetary scientists and engineers, representing a broad range of disciplines
• An extensive library of well characterised, close and part analogue samples (GSPARC) or access to analogous field sites
• An array of space qualified instruments, development prototypes and lab/field kit

Apart from the sample repository, which is centrally located and maintained, all these assets for the most part are disseminated worldwide. Study samples therefore migrate back and forth between labs and instruments travel to analogous sites during field campaigns. The entire project is coordinated centrally by the administrator of this website (Derek Pullan, derek@gsparc.com).

Membership of PAFS-net is open to anybody who can provide one of more of the following: -

• Expertise in a particular area of research or technology of relevance to the network
• Donation of appropriate, well documented specimens for inclusion in the GSPARC archive
• Experimental services such as appropriate lab and field instrumentation
• A compatible reference data resource (integrated into GSPARC or accessible via external link)

In order to raise the profile of both PAFS-net and GSPARC, all users (members or otherwise) are encouraged to include the following in all documentation produced as a result of a PAFS-net study or experiments involving GSPARC samples: -

• Use of GSPARC IDs where appropriate
• An acknowledgement of PAFS-net and GSPARC
• Reference to the site (www.gsparc.com)

A particularly useful aspect of PAFS-net is “blind testing”. These are coordinated exercises in which teams of researchers (usually representative of different disciplines) are presented with raw data sets acquired on unknown samples and asked to make a collective interpretation. Taken further these “sample blind tests” can be incorporated into “mission blind tests” (i.e. Planetary Yard or even in-field activities).