Did alien life exist in hot water on Mars billions of years ago?

I remember during the Clinton Admin, meteorite ALH84001 was hailed containing perhaps, little Martians. "Black Beauty" may have had hot water but nothing like ALH84001 fame is reported for it apparently.
 
Mar 5, 2021
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There is little evidence to prove what was in the meteorite was ever alive except it resembled a small worm. It was eventually concluded that the tubular was just an artifact of mineral formation.
 
Nice support for our own early ocean formation on a young crust, where zircons have dated it to 4.4 / 4.3 billion years ago.

There is little evidence to prove what was in the meteorite was ever alive except it resembled a small worm. It was eventually concluded that the tubular was just an artifact of mineral formation.
There were lots of evidence in ALH84001 at the time besides that singular clickbait image, but everyone of them have been rejected or found inconclusive:

Other meteorites that have potential biological markings have generated less interest because they do not contain rock from a "wet" Mars; ALH84001 is the only meteorite originating when Mars may have had liquid surface water.[3]

In October 2011, it was reported that isotopic analysis indicated that the carbonates in ALH84001 were precipitated at a temperature of 18 °C (64 °F) with water and carbon dioxide from the Martian atmosphere. The carbonate carbon and oxygen isotope ratios imply deposition of the carbonates from a gradually evaporating subsurface water body, probably a shallow aquifer meters or tens of meters below the surface.[9]

In April 2020, researchers reported discovering nitrogen-bearing organics in Allan Hills 84001.[15]

A later study in January 2022 concluded that ALH84001 did not contain Martian life; the discovered organic molecules were found to be associated with abiotic processes (i.e., "serpentinization and carbonation reactions that occurred during the aqueous alteration of basalt rock by hydrothermal fluids") produced on the very early Mars 4 billion years ago instead.[16][17]
In January 2010, a team of scientists at Johnson Space Center, including McKay, argued that since their original paper was published in November 2009, the biogenic hypothesis has been further supported by the discovery of three times the original amount of fossil-like data, including more "biomorphs" (suspected Martian fossils), inside two additional Martian meteorites, as well as more evidence in other parts of the Allan Hills meteorite itself.[23]

However, the scientific consensus is that "morphology alone cannot be used unambiguously as a tool for primitive life detection."[24][25][26] Interpretation of morphology is notoriously subjective, and its use alone has led to numerous errors of interpretation.[24]

Features of ALH84001 that have been interpreted as suggesting the presence of microfossils include:

  • The structures resemble some modern terrestrial bacteria and their appendages. Though some are much smaller than any known extant Earth microbes, others are of the order of 100–200 nm in size, within the size limits of Pelagibacter ubique, the most common bacterium on Earth, which ranges from 120 to 200 nm, as well as hypothetical nanobacteria. RNA organisms, which are expected to have lived on Earth during the time period when ALH84001 was ejected from Mars, may also have been as small or smaller than these structures, as modern RNA viruses and viroids are often as little as a few dozen nanometers. Some of the structures are even larger, 1–2 microns in diameter.[11] The smallest structures are too small to contain all the systems required by modern life.[3]
  • Some of the structures resemble colonies and biofilms.[11] However, there are many instances of morphologies that suggested life and were later shown to be due to inorganic processes.[11]
  • The meteorite contains magnetite crystals of the unusual rectangular prism type, and organized into domains all about the same size, indistinguishable from magnetite produced biologically on Earth and not matching any known non-biological magnetite that forms naturally on Earth.[11] The magnetite is embedded in the carbonate. If found on Earth it would be a very strong biosignature. However, in 2001, scientists were able to explain and produce carbonate globules containing similar magnetite grains through an inorganic process simulating conditions ALH84001 likely experienced on Mars.[3]
  • It contains polycyclic aromatic hydrocarbons (PAHs) concentrated in the regions containing the carbonate globules, and these have been shown to be indigenous. Other organics such as amino acids do not follow this pattern and are probably due to Antarctic contamination. However, PAHs are also regularly found in asteroids, comets and meteorites, and in deep space, all in the absence of life.[3][27]
https://en.wikipedia.org/wiki/Allan_Hills_84001
 

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