Wednesday, September 7, 2011

Desert RATS - Day 11 - Sample collection by Jake Bleacher

Jake Bleacher is doubling as crew and VAPoR team member. As part of the crew he is involved in all steps of the simulation, from collecting samples to processing them in the GeoLab to living in the DSH, simulating a planetary habitat. Here he describes his adventures during the sampling collection (also on the official NASA blog). 

Jake Bleacher:  One of the great advantages to sending humans to explore other Solar System bodies is the chance to document, collect, and analyze scientific samples. Here at Desert RATS we primarily focus on the collection of geologic samples, or rocks and soils. Although these samples can be studied in the Deep Space Habitat (DSH) Geolab, or back on Earth, it is extremely critical to document the context in which the samples are collected so that the science team can use those samples to piece together a geologic history for the area. The hammer, shovel, and tongs enable us to break off a piece of local rock or scoop up a sample of soil. However, prior to doing so we use cameras that are mounted on our backpacks to show the intended sample in its undisturbed location, preferably with the hammer or shovel in the picture to provide a sense of scale, or the size of the rocks.

Jake sampling (credit NASA/DRATS)

The SEV (credit NASA/DRATS

Crew member Jose Hurtado taking notes for the science team (credit NASA/DRATS) 

Once we pick up the rock or soil sample we describe its color, texture, size, and general makeup as well as any other important observations. This information helps the science backroom determine what type of sample it is. After collecting the sample we take a picture showing the sample along with its sample bag, with the number clearly visible. This enables us to keep track of what samples go in what bags. We also acquire an image showing the sample’s location once the sample has been collected to provide further context of the environment in which the sample was located. After an EVA is complete and we have returned to our Space Exploration Vehicle (SEV) we place all the samples on the aft deck (back end) of the rover and take one last photo. This helps the science team keep track of which samples were collected on which EVAs, because with so many samples being collected it just takes one computer error or malfunction to lose track of your samples. This picture provides another piece of data to help us keep track of that information. We weigh all of the samples in their storage locker and then place them into what we call the sample mailbox on the aft deck.
sample mailbox on the aft deck

This is our standard way of collecting geologic samples during Desert RATS. However, just like during the Apollo Missions, we also have what we call “special samples” that are collected in a slightly different way. This year we have two science instrument teams involved in the test. I am involved with one of these instruments, called Volatile Analysis by Pyrolysis of Regolith (VAPoR). This instrument has the potential to “sniff” out water or other volatiles that we might use to help survive on another planet. It can also help identify bio-signatures, or signs of past or present life. However, one problem with collecting our samples is that we ourselves create a bio-signature and are composed of water.  So our standard sample collection protocols can potentially contaminate a sample to the point that the instrument cannot identify minor traces of what it is looking for. As such, this year we have incorporated a new “special” sample collection protocol for VAPoR samples. Once a crewmember or the backroom identifies a possible VAPoR sample we are careful to not touch it with our gloves. We also never let the sample touch the bags. So we basically encase the sample in aluminum foil to isolate it from interactions with the gloves or bags. This is a first step for Desert RATS to incorporate new science instruments that are in development at different NASA Centers, and to begin thinking about the steps necessary to collect samples in a non-traditional way. 

Addition by Inge: The VAPoR team went out to collect a few samples of their own. This short movie shows Jim chipping of a rock and Inge collecting it in a clean way.

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