Mikkel, thanks for the reply. These are important insights, and exactly the sort of things I’m working on.
As well it should be. It’s not yet clear how ubiquitous such environments were, and its during a time where, on Earth at least, there is virtually no geological evidence. There is some preliminary data and work suggesting these conditions may have been global owing to a single giant impact (see Genda et al 2017; Benner et al. 2019, Zahnle et al. 2020), but its not clear whether this prebiotic chemistry is compatible with the hot and hazy environment that results (Zahnle et al. 2020).
It’s also not clear whether this chemistry could occur spontaneuously in these environments, even if they were available.
That’s right. Although Earth hasn’t kept a good record of its first 500 million years, we can look elsewhere in our solar system (especially Mars, see Sasselov et al. 2020) and outside our solar system. Specifically, we can look toward young rocky planets, going through the phase we might have, to see if the precursor compounds are present in those planets atmospheres.
On the much longer term, if life is reasonably common, we can use the distribution of life detections on exoplanets to figure out what scenarios are more plausible universally. Do they all cluster around stars with sufficient UV light (Rimmer et al. 2018)? Are they present on ocean worlds, up to a certain water content (those likely to have hydrothermal vents)? Or is their distribution based on some other criterion or criteria? It’s just as you say, looking at other worlds might give us the clearest insight about our own in this regard. If life is sufficiently common.
If life is rare, then we’ll learn that instead, but that’s about all we’ll learn from outside our solar system, at least in the foreseeable future.
Benner, S.A., Bell, E.A., Biondi, E., Brasser, R., Carell, T., Kim, H.J., Mojzsis, S.J., Omran, A., Pasek, M.A. and Trail, D., 2019. When Did Life Likely Emerge on Earth in an RNA‐First Process? ChemSystemsChem, 2, e1900035
Genda, H., Brasser, R. and Mojzsis, S.J., 2017. The terrestrial late veneer from core disruption of a lunar-sized impactor. Earth and Planetary Science Letters, 480, 25.
Rimmer, P.B., Xu, J., Thompson, S.J., Gillen, E., Sutherland, J.D. and Queloz, D., 2018. The origin of RNA precursors on exoplanets. Science advances, 4, p.eaar3302.
Sasselov, D.D., Grotzinger, J.P. and Sutherland, J.D., 2020. The origin of life as a planetary phenomenon. Science Advances, 6, p.eaax3419.
Zahnle, K.J., Lupu, R., Catling, D.C. and Wogan, N., 2020. Creation and Evolution of Impact-generated Reduced Atmospheres of Early Earth, The Planetary Science Journal, 1, 11