Boy, are they ever talking about something they say was found in the asteroid Bennu. But it's mainly more "science slop" baloney.
An example is the recent Fake News headline in the often-erring New York Post, a paper I am not very proud to have as an example of my local New York City newspapers. It is the doubly untrue headline "Asteroid hurtling toward Earth found to be teeming with building blocks of life: researchers." The title refers to the asteroid Bennu, which is not "hurtling towards Earth." And the chemicals referred to (which probably do not even exist on Bennu) are chemicals claimed to have been detected in only the tiniest trace amounts, such as 1 part in a billion -- a level that can never truthfully be described as "teeming."
What happened was that a spacecraft (OSIRIS-REx) retrieved a small sample of soil from the asteroid Bennu, and the sample was brought back to Earth. Scientists analyzing the sample reported the tiniest trace amounts of some amino acids and some of the nucleobases used in RNA, along with some sugars. However, the reported amounts were all so small we can have no confidence in the reported results. In all likelihood, they are simply due to earthly contamination, which could have occurred at any of many different stages of the scooping up/earthly retrieval/earthly analysis process.
The December 2025 paper that is the inspiration for such clickbait is one co-authored by Daniel P. Glavin, and entitled "Bio-essential sugars in samples from asteroid Bennu." We read a claim of a detection of sugars, but the abundance levels are negligible. The paper states this:
"The abundances of ribose, lyxose, arabinose and xylose were 0.097 ± 0.014, 0.018 ± 0.007, 0.11 ± 0.03 and 0.079 ± 0.033 nmol g−1, respectively (Table 1). Glucose had the highest concentration of the sugars at 0.35 ± 0.05 nmol g−1, whereas galactose was 0.014 ± 0.004 nmol g−1 (Table 1)."
The phrase "nmol g" means nanomole per gram. The reported abundance are less than 1 nanomole per gram, which is roughly something like 1 part per billion. When a claim is made to have detected something at a level so small, we can have no confidence that the result actually came from space, as opposed to resulting from earthly contamination.
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 from trace amounts from Earth that were left on the spacecraft when it reached the asteroid Bennu.
The relevant threshold here is 180 nanograms per square centimeter. Anything greater than such an amount might be evidence of amino acids or sugars picked up from the asteroid Bennu. Anything less than that we can have no confidence in, and should regard as purely the result of earthly contamination. None of the "building blocks of life" reportedly detected from the asteroid Bennu exceeds this threshold. They are all much less than the threshold.
So we can have no reasonable confidence in any of these reports of detecting amino acids or nucleobases or sugars from material retrieved from the asteroid Bennu. No reliable evidence has been presented that anything relevant to life was discovered on the asteroid Bennu.
The latest paper confesses, "The abundances of the biologically important sugars in the Bennu sample (glucose, arabinose, ribose and xylose) might nevertheless suggest the possibility of contamination." The valine row in Extended Data Table 4 of the paper suggests that earthly contamination was occurring. There is a "d/l" ratio of .5, which is not the 1.0 ratio we would expect if there was no earthly contamination of the sample.
What almost always happens in such press reports is that writers pay zero attention to the negligible levels of the chemicals found, and the writers pay zero attention to the all-important issue of contamination, explained in the infographic above.
The New York Post article quotes the sometimes-misspeaking astronomer Avi Loeb as claiming, "The finding that the asteroid Bennu contains most amino acids, the building blocks of life-as-we-know-it suggests that these building blocks are common in the Universe." No, supposedly finding something in only the tiniest trace amounts of a few parts per billion does not suggest that something is common. And in this case no reliable evidence has been gathered that anything relevant to life was discovered in space, because of the very high chance of earthly contamination. And amino acids are not actually the "building blocks of life." The building components of one-celled life are protein molecules, which are very special arrangements of amino acids, arrangements fantastically unlikely to arise by chance. Components requiring so many specially arranged parts should never be referring to as "building blocks," as if they were simple.
Astronomers have been making these kind of misstatements for 50 years. Astronomer Carl Sagan told us the same baloney, when he falsely claimed this: "The carbon-rich complex molecules that are essential for the kind of life we know about, are fantastically abundant. They litter the universe." There are no reports of detecting amino acids, sugars or nucleobases in space, in anything more than the tiniest trace amounts; and such reports are typically unreliable, involving very large uncertainties that make them weak from an evidence standpoint.
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