[BBG02-01] Search for biosignatures on Mars by the Life-signature Detection Microscope (LDM)
Keywords:Fluorescent microscope, Astrobiology
The Life-signature Detection Microscope (LDM), which we have proposed , has the potential sensitivity much higher than the Viking instrument. The LDM is based on fluorescent microscopy and detects organic compounds, membrane structures, and catalytic activities stained by fluorescent pigments. This technique is especially useful for the detection of living microbes. It has the potential to detect a single cell and visualizes their shapes, sizes, and other morphological structures at a spatial resolution of 1 µm. The sensitivity can also be as high as desired just by increasing the volume of the sample to be scanned in a reasonable duration of experiments. LDM scans about 1 mm3 and detects less than 104 cells in 1 gram soil, which is comparable to the least populated area of the terrestrial environment on Earth, such as the Atacama desert in Chile. If microbes are not detected, we can determine the upper limit of the microbial density, which is useful information to evaluate the risk of human contact with Martian microbes in future manned explorations.
Currently, we have been developing the breadboard model (BBM) of LDM. We will report the current status of the BBM and discuss how and where to find biosignatures on Mars.
 Eigenbrode, J. L., et al., Science, 360 (2018) 1096-1101.
 Webster, C. R., et al., Science, 360 (2018) 1093-1096.
 Ming, D., et al., Science, 343 (2014) 1245267.
 Yamagishi, A., et al., Biological Sciences in Space, 24 (2010) 67-82.
 Ojha, L., et al., Nature Geosci, 8 (2015) 829-832.
 Mancinelli, R. L., et al., Planetary and Space Science, 48 (2000) 1093-1097.
 Margulis, L., et al., J. Mol. Evol., 14 (1979) 223-232.
 Glavin, D. P., et al., Earth and Planetary Science Letters, 185 (2001) 1-5.
 Navarro-Gonzalez, R., et al., Proc Natl Acad Sci U S A, 103 (2006) 16089-16094.
 Yamagishi, A., et al., Trans. JSASS, Aerospace Technology Japan, 16 (2018) 299-305.