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Confidence Of Life Detection
Confidence of Life Detection Scale (CoLD) or the Ladder of Life Detection is a numerical scale developed by NASA astrobiologists to assess possible biosignatures of extraterrestrial life. It was suggested in 2018. The scale is designed similar to NASA’s technological readiness scale. It is a seven-step scale: # Detect possible signal # Rule out contamination # Make sure biology is possible # Rule out non-biology # Find additional independent signal # Rule out other hypothesis # Independent confirmation History NASA's "working definition of life" is "self-sustaining chemical system capable of Darwinian evolution". As of 2025, the only NASA mission designed to look for life was the Viking program to Mars, launched in 1976. Per Neveu et al.: The Ladder is designed to "define the burden of proof that must be met to convince a majority of the scientific community of such a discovery." Neveu et al. lists eight criteria: Examples The Cheyava Falls rock, found by the ''Perseve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrobiology
Astrobiology (also xenology or exobiology) is a scientific field within the List of life sciences, life and environmental sciences that studies the abiogenesis, origins, Protocell, early evolution, distribution, and future of life in the universe by investigating its deterministic conditions and contingent events. As a discipline, astrobiology is founded on the premise that life may exist beyond Earth. Research in astrobiology comprises three main areas: the study of planetary habitability, habitable environments in the Solar System and beyond, the search for planetary biosignatures of past or present extraterrestrial life, and the study of the Abiogenesis, origin and Protocell, early evolution of life on Earth. The field of astrobiology has its origins in the 20th century with the advent of space exploration and the discovery of exoplanets. Early astrobiology research focused on the search for extraterrestrial life and the study of the potential for life to exist on other pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biosignature
A biosignature (sometimes called chemical fossil or molecular fossil) is any substance – such as an element, isotope, molecule, or phenomenon – that provides scientific evidence of past or present life on a planet. Measurable attributes of life include its physical or chemical structures, its use of free energy, and the production of biomass and wastes. The field of astrobiology uses biosignatures as evidence for the search for past or present extraterrestrial life. Candidate biosignatures strongly indicate some of the earliest known life forms, aid studies of the origin of life on Earth as well as the possibility of life on Mars, Venus and elsewhere in the universe. Types Biosignatures can be grouped into ten broad categories:NASA Astrobiology Str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extraterrestrial Life
Extraterrestrial life, or alien life (colloquially, aliens), is life that originates from another world rather than on Earth. No extraterrestrial life has yet been scientifically conclusively detected. Such life might range from simple forms such as prokaryotes to Extraterrestrial intelligence, intelligent beings, possibly bringing forth civilizations that might be Kardashev scale, far more, or far less, advanced than humans. The Drake equation speculates about the existence of sapient life elsewhere in the universe. The science of extraterrestrial life is known as astrobiology. Speculation about the possibility of inhabited worlds beyond Earth dates back to antiquity. Early Christianity, Christian writers discussed the idea of a "plurality of worlds" as proposed by earlier thinkers such as Democritus; Augustine of Hippo, Augustine references Epicurus's idea of innumerable worlds "throughout the boundless immensity of space" in ''The City of God''. Pre-modern writers typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viking Program
The ''Viking'' program consisted of a pair of identical American space probes, ''Viking 1'' and ''Viking 2'' both launched in 1975, and landed on Mars in 1976. The mission effort began in 1968 and was managed by the NASA Langley Research Center.Soffen, G. A. (July–August 1978). "Mars and the Remarkable Viking Results." ''Journal of Spacecraft and Rockets''. 15 (4): 193-200. Each spacecraft was composed of two main parts: an orbiter spacecraft which photographed the surface of Mars from orbit, and a Lander (spacecraft), lander which studied the planet from the surface. The orbiters also served as communication relays for the landers once they touched down. The Viking program grew from NASA's earlier, even more ambitious, Voyager program (Mars), Voyager Mars program, which was not related to the successful Voyager program, Voyager deep space probes of the late 1970s. ''Viking 1'' was launched on August 20, 1975, and the second craft, ''Viking 2'', was launched on September 9, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheyava Falls
Cheyava Falls is a rock discovered on Mars by NASA's ''Perseverance (rover), Perseverance'' rover during its exploration of the Jezero Crater. This rock, named after a Grand Canyon waterfall, has drawn significant attention due to its potential as an indicator of ancient life on Mars. The rover's instruments detected organic compounds within the rock, which are essential for all known life. According to NASA, Cheyava Falls "possesses qualities that fit the definition of a possible indicator of ancient life". "Cheyava Falls" is characterized by large white calcium sulfate veins and bands of reddish material, indicative of hematite, a mineral that gives Mars its rusty color. The veins are "filled with millimeter-size crystals of olivine". The rock features millimeter-sized off-white splotches surrounded by black material, resembling "leopard spots." These spots contain iron and phosphate, elements often associated with microbial life. According to a seven-step scale called Confiden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perseverance (rover)
''Perseverance'' is a car-sized Mars rover designed to explore the Jezero (crater), Jezero crater on Mars as part of NASA's Mars 2020 mission. It was manufactured by the Jet Propulsion Laboratory and launched on July 30, 2020, at 11:50 Coordinated Universal Time, UTC. Confirmation that the rover successfully landed on Mars was received on February 18, 2021, at 20:55 UTC. As of , ''Perseverance'' has been active on Mars for Sol (day on Mars), sols ( days, Earth days, or ) since its landing. Following the rover's arrival, NASA named the landing site Octavia E. Butler Landing. ''Perseverance'' has a similar design to its predecessor rover, ''Curiosity (rover), Curiosity'', although it was moderately upgraded. It carries seven primary payload instruments, nineteen cameras, and two microphones. The rover also carried the mini-helicopter ''Ingenuity (helicopter), Ingenuity'' to Mars, an experimental technology testbed that made the first powered aircraft flight on another plane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it is difficult because it is a gas at standard temperature and pressure. In the Earth's atmosphere methane is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. Methane is an Organic chemistry, organic Organic compound, compound, and among the simplest of organic compounds. Methane is also a hydrocarbon. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the Atmosphere of Earth, atmosphere, it is known as atmospheric methane. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
