Once Again, We Get Building-Block Bamboozled

The building components of even the simplest one-celled life are proteins. Even the simplest one-celled life requires hundreds of different types of proteins. No trace of such proteins can be found anywhere in space. But scientists do make some attempts to look for the building components of the building components of life, by looking for relatively simple molecules such as amino acids. Such searches never find anything more than negligible amounts of such amino acids. 

But people announcing such results have long followed a trickster algorithm to fool people into thinking that their basically-nothing observational results are very important.  Below are the elements of this trickster algorithm:

(1) A press release will be released, using the misleading phrase "building blocks of life." Such a term is always misleading when describing mere amino acids. Cells are not made from things so simple that they can honesty be called "building blocks." Cells are made from hundreds of types of very highly organized components, different types of protein molecules. Amino acids are merely the building components of the building components of life; and the building components of life are very complex protein molecules, not amino acids.  And since amino acids have to be very specially arranged to make a functional protein molecule, in a way as hard-to-achieve by chance as the letters in a long well-written paragraph, it is very misleading to call amino acids "building blocks of life," thereby implying that a living thing can be made by some "any sequence works" method, like how any sequence of building blocks can make a wall.   

(2) The press release will make no mention at all of the abundance level of the chemical found, which is always some negligible trace amount such as a few parts in a billion. 

(3) The press release will make no mention of how possibilities of earthly contamination make all reports of very tiny trace amounts of chemicals retrieved from space unreliable and not-to-be-trusted, because the reported amounts are so small they are less than the expected amounts to be produced by earthly contamination. 

What will then happen is that the mainstream media will fall "hook, line and sinker" for the misleading press release. All or almost all of the resulting news stories will repeat the misleading headline of the press release. None or almost none of the resulting news stories will report the abundance levels reported in the scientific paper, which will be only the tiniest trace amount.  All or almost all of the resulting news stories will fail to tell us that only the tiniest trace amounts were found. None or almost none of the resulting news stories will discuss the very high possibility or likelihood that the detected trace amounts are due to earthly contamination. 

The latest example of this in that in January 2025 the journal Nature published a paper by D. Glavin and others, analyzing  a sample retrieved from the asteroid Bennu sample, the paper "Abundant ammonia and nitrogen-rich soluble organic matter in samples from asteroid (101955) Bennu." The sample was retrieved by the OSIRIS-REx mission. As shown in Extended Data Table 3, which you can see here, the most abundant protein-related amino acid found (glycine) was found at a level of only 44 nanomoles per gram, a negligible amount of only about .00000004 moles per gram.  All other protein-related amino acids were found at a level of less than 5 nanomoles per gram. 

Scientists use methods to prevent contamination when analyzing samples from space, but there is no reason to believe that such efforts are entirely effective.  There are two potential sources of contamination. A spacecraft may contain trace amounts of amino acids from Earth when it lands on another planet or asteroid.  Once  a sample is returned to Earth, there are endless possibilities for contamination, because amino acids are everywhere on Earth. You cannot easily decontaminate by mere sterilization, because sterilization just kills microbes, without removing all amino acid traces. 

The paper here ("OSIRIS-REx Contamination Control Strategy and Implementation") tells us about methods to prevent microbes and amino acids from existing on the Osiris/REx spacecraft that gathered the sample from the asteroid Bennu. It claims, "To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm² of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance."  This is a mention of some standard of cleanliness that was a target level, and we have no guarantee that such a target level of cleanliness was actually obtained. Moreover, the standard of cleanliness mentioned is less than 180 nanograms per square centimeter.  Under such a standard, we might expect that you would get tiniest trace amounts results as reported by Glavin  (no better than 44 nanomoles per gram) from trace amounts from Earth that were left on the spacecraft when it reached the asteroid Bennu. Or, if such a standard had been followed after samples had been returned, we might have easily got the tiny trace amounts of amino acids reported by Glavin, purely from earthly contamination after the samples had been returned. 

Extended Data Table 4 of the paper (which you can see here) gives us some estimates of the ratio of left-handed to right-handed amino acids in the amino acids reportedly found. The main part of the table is below.  If you have a reliable measurement that amino acids are in equal amounts left-handed and right-handed, that can be an indication that the amino acids are not from earthly contamination. (Earthly amino acids used in life are almost all left-handed). The columns marked  L_ee are the degree of uncertainty in the measurements.   

Unfortunately, because the numbers in these uncertainty columns are so high, and because the reported amounts of amino acids are so tiny (no greater than 44 nanomoles per gram), we can have no confidence that any of the reported amino acids actually come from the asteroid Bennu.  The reported nucleobases found (uracil, thymine, cytosine, adenine and guanine) are all reported to have been found at a level of less than 1 nanomole per gram (Extended Data Table 6, which you can see here). This is a negligible trace amount, an amount so small we can have no confidence that the result is from the asteroid Bennu itself, rather than from earthly contamination. 

Reporting on these results, a story on Reuters gives has the misleading headline "Building blocks of life found in samples from asteroid Bennu."  This is the deception that has gone on for so many decades in origin-of-life news reports.  Amino acids are not "building blocks of life" but instead building components of the building components (proteins) of the simplest living things (one-celled life). Since proteins require very special arrangements of amino acids (as special and as hard-to-achieve-by-chance as the arrangements of letters in well-written paragraphs), and since even the simplest living things cannot be made directly from amino acids, it is deceptive to call amino acids "building blocks of life."  Building blocks are things that can be assembled in any order, not things like letters and characters and amino acids that have to be placed in a very special order that chance would not produce. 

In the Reuters article scientist Danny Glavin speaks in a misleading way.  Failing to tell us about how negligible are the reported amounts of amino acids and nucleobases, and misleadingly calling amino acids "building blocks of life," Glavin says, "The detection of these key building blocks of life in the Bennu samples supports the theory that asteroids and their fragments seeded the early Earth with the raw ingredients that led to the emergence of life."  No, it sure does not, given the negligible amounts detected, and given the high chance that most or all of the life-relevant amounts were due to earthly contamination. And you don't get life by the mere deposit of "raw ingredients" -- even the simplest life requires an incredibly special arrangement of matter gigantically unlikely to occur by chance.  Glavin also falsely claims that "these chemical building blocks of life...are widespread throughout the solar system." No, they are not. No one has found protein-related amino acids or nucleobases on Mars, and no one has found protein-related amino acids or nucleobases in either asteroids or comets, except in negligible amounts such as those reported in Glavin's paper. Glavin says not a word about the very large earthly contamination possibilities that cast all studies such as his into doubt, saying only, "We can trust these results." 

Almost all of the mainstream news reports on this paper have been as misleading as the Reuters article. It seems none of these science journalists are doing their jobs decently, by reporting on the levels detected, which are negligible, and so low they are what we would expect from earthly contamination.  

The Glavin paper does not seem to adequately address the issue of potential earthly contamination. It uses the word "contamination" only a few times, in mere passing references. The 2020 paper "Concerns of Organic Contamination for Sample Return Space Missions" tells us this about the earthly contamination of samples returned from space:

"Organic contamination is to some degree inevitable. Contaminants can potentially be accrued during the design and construction of the spacecraft and associated components, on the course of the mission, during the sample recovery and curation processes, and/or during sample characterisation after their dissemination to analytical teams. For example, the lunar samples returned by the Apollo missions were found to contain amino acids derived from terrestrial biological contamination...... Preflight monitoring of the nitrogen-purged sample cabinet desiccator box by the OSIRIS-REx team also showed a steady increase of volatile compounds although at very small amounts (Dworkin et al. 2017)."

There are two other reasons for thinking that the possibilities for contamination may have been high:

(1) There was an unexpected glitch in which NASA scientists spent three months fiddling with the Bennu sample container top that resisted opening, before finally getting the top open. That may have had who-knows-what effect on whatever contamination prevention protocol was in effect. 

(2) An article at the site Salon tells us that when a soil sample was analyzed from the asteroid Ryugu, under conditions supposed to prevent contamination, the sample was contaminated not merely by amino acids but by something many times larger: microbes. We are referred to a paper entitled "Rapid colonization of a space-returned Ryugu sample by terrestrial microorganisms." We read this:

"The population statistics indicate an extant microbial community originating through terrestrial contamination. The discovery emphasizes that terrestrial biota can rapidly colonize extraterrestrial specimens even given contamination control precautions."

If entire microbes (millions of times bigger than amino acids) can get through the contamination prevention measures of scientists analyzing samples from asteroids, then can we have any confidence that most of the amino acids detected at the tiniest trace amounts of only 44 nanomoles per gram (or less) actually came from an asteroid rather than from terrestrial contamination? No, we cannot.