Modern astrobiology inquiry has emphasized the search for water on Mars, chemical biosignatures in the permafrost, soil and rocks at the planet's surface, and even biomarker gases in the atmosphere that may give away the presence of past or present life. The detection of preserved organic molecules of unambiguous biological origin is fundamental for the confirmation of present or past life, but the 1976 Viking lander biological experiments failed to detect organics on Mars, and it is suspected it was because of the combined effects of heat applied during analysis and the unexpected presence of oxidants such as perchlorates in the Martian soil. The recent discovery of near surface ground ice on Mars supports arguments for the long-term preservation of biomolecules on Mars.
SOLID demonstrated that antibodies are unaffected by acidity, heat and oxidants such as perchlorates, and it has emerged as a viable choice for an astrobiology mission directly searching for biosignatures.
For a time, the ExoMars Rosalind Franklin' rover was planned to carry a similar instrument called Life Marker Chip.