The SAG is a good point to discuss. Thing is, that document was written a couple of years before the skycrane was demonstrated with its small landing ellipse. Here's a question - given the reduced landing ellipse afforded by skycrane, and longevity/driving distance demonstrated by MER, isn't it possible to forego the expansive instrument suite and land a simpler rover within driving distance of MSL's site? Less instrumentation means less cost, among other things.
Marc's suggestion would effectively be the equivalent of the "2-element" sample return mission described in the SAG report, with MSL the first leg of the mission. Certainly, if MSL finds something with great potential interest, it should be given serious consideration as a site to return to to retrieve samples. However, as Steve mentioned earlier, even with the amazing landing capabilities of the skycrane, it is difficult to ensure that we would be close enough to the Curiosity landing site to be certain to see the same stuff. If not, the mission would be left grabbing samples with limited information to go on ...
I agree with Tom's comments, we need to do as much as possible of in situ analyses on Mars before putting samples in the collection bag - we will only get one chance.
We also need to test these analytical methods and instruments in the field, in a selection of analogs environments - we know there is life there. If those instruments cannot see a collection of microbes in an Antarctica rock, they won't find anything on Mars.
I just rejoined and find the discussion turning to the question of how to look for life. I think it is worth pointing out that there is a high TRL instrument that can search for biomarker compounds using immunoassay at very high sensitivity. This is the spanish Signs of Life Detector (SOLID) instrument.
The biomarkers can be modern or ancient, and the current instrument can assay for up to 500 individual compounds. Some biomarker compounds are short lived, like ATP, and so would only be diagnostic of modern life, while others like lipids can be sequestered and survive in ancient rocks. There are a number of references to work that has been done with this instrument in field sites including Atacama soils and drilled soil cores from Atacama, deep subsurface rocks in massive sulfide deposit in Rio Tinto, and Antarctic samples. See for example Parro et al. Astrobiology Vol 11, No. 1, 2011, DOI:10.1089/ast.2010.0501. A similar instrument was part of ExoMars mission but I have now heard that has been descoped. This instrument does require admission of particulate samples, and aqueous processing, but is still a simpler instrument than SAM.
The fact that this instrument has been used to successfully detect biomarkers of life from a wide range of potential Mars analog environments in actual field situations proves the relevance of the technique. The real challenge for this instrument is to identify the compounds most relevant as biomarkers that may be generic to an independent genesis of life.
I just rejoined and find the discussion turning to the question of how to look for life. I think it is worth pointing out that there is a high TRL instrument that can search for biomarker compounds using immunoassay at very high sensitivity. This is the spanish Signs of Life Detector (SOLID) instrument.
The biomarkers can be modern or ancient, and the current instrument can assay for up to 500 individual compounds. Some biomarker compounds are short lived, like ATP, and so would only be diagnostic of modern life, while others like lipids can be sequestered and survive in ancient rocks. There are a number of references to work that has been done with this instrument in field sites including Atacama soils and drilled soil cores from Atacama, deep subsurface rocks in massive sulfide deposit in Rio Tinto, and Antarctic samples. See for example Parro et al. Astrobiology Vol 11, No. 1, 2011, DOI:10.1089/ast.2010.0501. A similar instrument was part of ExoMars mission but I have now heard that has been descoped. This instrument does require admission of particulate samples, and aqueous processing, but is still a simpler instrument than SAM.
The fact that this instrument has been used to successfully detect biomarkers of life from a wide range of potential Mars analog environments in actual field situations proves the relevance of the technique. But these are testing life on Earth where the biomarkers are known. The real challenge for this instrument is to identify the biomarkers that are sufficiently fundamental that they may be generic to an independent genesis of life.
The SAG is a good point to discuss. Thing is, that document was written a couple of years before the skycrane was demonstrated with its small landing ellipse. Here's a question - given the reduced landing ellipse afforded by skycrane, and longevity/driving distance demonstrated by MER, isn't it possible to forego the expansive instrument suite and land a simpler rover within driving distance of MSL's site? Less instrumentation means less cost, among other things.
Marc's suggestion would effectively be the equivalent of the "2-element" sample return mission described in the SAG report, with MSL the first leg of the mission. Certainly, if MSL finds something with great potential interest, it should be given serious consideration as a site to return to to retrieve samples. However, as Steve mentioned earlier, even with the amazing landing capabilities of the skycrane, it is difficult to ensure that we would be close enough to the Curiosity landing site to be certain to see the same stuff. If not, the mission would be left grabbing samples with limited information to go on ...
I agree with Tom's comments, we need to do as much as possible of in situ analyses on Mars before putting samples in the collection bag - we will only get one chance.
We also need to test these analytical methods and instruments in the field, in a selection of analogs environments - we know there is life there. If those instruments cannot see a collection of microbes in an Antarctica rock, they won't find anything on Mars.
I just rejoined and find the discussion turning to the question of how to look for life. I think it is worth pointing out that there is a high TRL instrument that can search for biomarker compounds using immunoassay at very high sensitivity. This is the spanish Signs of Life Detector (SOLID) instrument. The biomarkers can be modern or ancient, and the current instrument can assay for up to 500 individual compounds. Some biomarker compounds are short lived, like ATP, and so would only be diagnostic of modern life, while others like lipids can be sequestered and survive in ancient rocks. There are a number of references to work that has been done with this instrument in field sites including Atacama soils and drilled soil cores from Atacama, deep subsurface rocks in massive sulfide deposit in Rio Tinto, and Antarctic samples. See for example Parro et al. Astrobiology Vol 11, No. 1, 2011, DOI:10.1089/ast.2010.0501. A similar instrument was part of ExoMars mission but I have now heard that has been descoped. This instrument does require admission of particulate samples, and aqueous processing, but is still a simpler instrument than SAM.
The fact that this instrument has been used to successfully detect biomarkers of life from a wide range of potential Mars analog environments in actual field situations proves the relevance of the technique. The real challenge for this instrument is to identify the compounds most relevant as biomarkers that may be generic to an independent genesis of life.
I just rejoined and find the discussion turning to the question of how to look for life. I think it is worth pointing out that there is a high TRL instrument that can search for biomarker compounds using immunoassay at very high sensitivity. This is the spanish Signs of Life Detector (SOLID) instrument. The biomarkers can be modern or ancient, and the current instrument can assay for up to 500 individual compounds. Some biomarker compounds are short lived, like ATP, and so would only be diagnostic of modern life, while others like lipids can be sequestered and survive in ancient rocks. There are a number of references to work that has been done with this instrument in field sites including Atacama soils and drilled soil cores from Atacama, deep subsurface rocks in massive sulfide deposit in Rio Tinto, and Antarctic samples. See for example Parro et al. Astrobiology Vol 11, No. 1, 2011, DOI:10.1089/ast.2010.0501. A similar instrument was part of ExoMars mission but I have now heard that has been descoped. This instrument does require admission of particulate samples, and aqueous processing, but is still a simpler instrument than SAM.
The fact that this instrument has been used to successfully detect biomarkers of life from a wide range of potential Mars analog environments in actual field situations proves the relevance of the technique. But these are testing life on Earth where the biomarkers are known. The real challenge for this instrument is to identify the biomarkers that are sufficiently fundamental that they may be generic to an independent genesis of life.
Pages