Glossary

Abiotic

associated with non-living matter or processes

Activated

the increasing reactivity of a molecule when energy is applied

Adsorbed

the accumulation of molecules onto a surface of a solid

Archaea

a domain of life consisting of single celled microbes

Astrobiology

the study of the potential for life beyond the Earth

Backward contamination

the transfer of biological organisms or organic molecules from space to Earth

Bacteria

a domain of life consisting of single celled microbes

Bioburden

a measure of all the microorganisms living on a surface

Biocidal

a substance or process that destroys all living organisms

Biogenic minerals

minerals produce by microbes directly or indirectly

Biohazards

a biological substance that could pose a threat to human health or the environment

Biological assay

a controlled chemical environment in which organisms can be detected and quantified

Biosignatures

a chemical or physical product that indicates the presence, or former presence, of life

Biotic

associated with living matter or processes

Cells

the basic biological building block of living organisms

Colony forming units (CFUs)

a measure of the number of viable microbes that could multiply and form colonies

Contamination

the process of making something less clean by introducing unwanted organisms or chemicals

Desorb

the release of a substance from a surface

Extant

current or existing life

Extinct

past life, no longer in existence

Extremotolerant

organisms that can survive, but perhaps not thrive, in extreme environmental condition

Extremophile

organisms that thrive in extreme environmental conditions

False negative

a result that indicates the absence of something, even though it is present.

False positive

a result that indicates the presence of something, even though it is not

Fixated

the attachment of molecules to a surface and becoming stable and unreactive

Forward contamination

the transfer of biological organisms or organic molecules from Earth to space

Growth medium

a solution used to grow microbes containing essential nutrients and energy sources

Hazard

a potential source of harm and can be an object or a situation that poses a level of threat to life, health, property or environment

Hydrophobic

a molecule that is repelled from water molecules

In-situ resource utilisation (ISRU)

extraction of resources from a planetary body for use as resources in space exploration of other activities

Microbes

a microscopic organism including bacteria, archaea, fungi, viruses and algae

Metabolism

the essential chemical processes that operate within an organism to sustain life

Molecular organic contamination (MOC)

organic molecules unrelated to biology that can cause contamination

Organic molecules

compounds that contain carbon

Payloads

the part of a spacecraft that performs its primary objective, and can include instruments, equipment and people

Period of biological exploration (PBE)

the time needed for a robotic mission to operate at a potentially habitable environment and detect biological life

Positive pressure

a state where the pressure inside a system is higher than around it

pre-biotic

Molecules that formed in the early Solar System that may have been the building blocks of the first life.

Regolith

a layer loose, unconsolidated material covering a rocky surface, sometimes referred to as soil

Risk

exposure to a hazard with the possibility of harm

Risk Assessment

an assessment of the possibility harm from a hazard

Sample return mission

missions that return samples of other planetary bodies to Earth

Special Regions

regions of Mars determined as scientifically important for the search for life and so are subject to stringent planetary protection requirements

Spores

a shell created by some microorganisms that allows them to survive inhospitable condition

Viable organisms

organisms that are alive and can perform essential biological functions

virus

An infectious microorganism that can only replicate within another living organism. Viruses are not considered living or non-living.

Volatile organic compound (VOC)

carbon-containing compounds that easily evaporate at room temperature

Water activity

a measurement of the availability of water to biological processes

Witness plates

a sample surface of known composition used to assess contamination by observing the accumulation of contaminants on it