Oxygen in comet atmosphere undermines billions of years
In 2004, the European Space Agency launched the space probe Rosetta to study asteroids and comets. In November 2014, its lander Philae touched down on comet 67P/Churyumov–Gerasimenko. The probe also carried a mass spectrometer ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis). This made “the most surprising discovery” about the comet to date, according to Principal Investigator Kathrin Altwegg of the University of Bern, Switzerland.1
There was a lot of free oxygen gas (O2) in the comet coma (or atmosphere)—almost 4% as much as the most abundant gas, water vapour.2 In fact, it was consistently high over seven months from September 2014 to March 2015.
However, this poses many problems for evolutionary models of the solar system,3 and was most unexpected. The problem is that oxygen is very reactive, so as Dr Altwegg explains, “We had never thought that oxygen could ‘survive’ for billions of years without combining with other substances.”1
One possible source would be from ultraviolet (UV) light splitting water molecules into hydrogen and oxygen. But for most of the comet’s lifetime, it would have been in the Kuiper Belt beyond Neptune. UV would be able to penetrate only a few metres to produce oxygen at that distance, but when the comet came into the inner solar system, all that material would have evaporated. So this would remove any oxygen produced during its time in the Belt. So is the oxygen being produced by UV in the comet’s brief time nearer the sun? Apparently not, because we don’t see large changes in oxygen concentration, nor do we find ozone (O3),2 which is produced in our own atmosphere by UV attacking O2 molecules.4
So the only remaining solution is that the oxygen was primordial: incorporated into the comet nucleus when it was formed. The researchers suggest that it came from UV radiation breaking off oxygen from water molecules in ice grains, the oxygen being trapped in voids in the ice, and those grains being incorporated into the comet. However, the researchers say, “Current Solar System formation models do not predict conditions that would allow this to occur.”2
Implication for chemical evolution
For the last six decades, it has been a widely believed myth that life on Earth evolved in a primordial soup.5 The basic chemicals in the soup were allegedly generated by UV radiation and lightning in a primordial atmosphere unlike the present one. It was allegedly ‘reducing’, meaning it contained hydrogen-rich compounds like methane (CH4) and ammonia (NH3) and lacked oxygen. Our current ‘oxidizing’ atmosphere would prohibit all this, because oxygen would destroy the so-called building blocks, and indeed prevent their formation in the first place.
It surprises many to realize that this theory is not driven by evidence but by the dogma that life evolved by spontaneous generation—no intelligence allowed, by decree. But there is good evidence against this naturalistic hypothesis, from a highly oxidized form of the rare earth metal cerium (Ce4+) found in zircons ‘dated’ at 4.35 billion years old.6,7 Now this enigmatic discovery of primordial oxygen in a comet is further evidence that we can’t rule out primordial oxygen on Earth either.
References and notes
- Sample, S., Rosetta finds oxygen on comet 67P in ‘most surprising discovery to date’: Oxygen revealed to be fourth most abundant gas in the comet’s atmosphere, contradicting long-held theories of comet formation, Guardian (UK), 29 October 2015. Return to text.
- Bieler, A. et al., Abundant molecular oxygen in the coma of comet 67P/Churyumov–Gerasimenko, Nature 526(7575):678–81, 29 October 2015 | doi:10.1038/nature15707. Return to text.
- Cesare, C., Rosetta sniffs oxygen around comet 67P: The presence of the gas could have implications for theories of the early Solar System, Nature News, 28 October 2015. Return to text.
- UV breaks O₂ into reactive oxygen atoms, O, which then attack other O₂ molecules: O₂ → 2O then O + O₂ → O₃. Return to text.
- For critiques, see Evolution’s Achilles’ Heels, ch. 3, CBP, 2014; available from creation.com/s/10-2-640; Batten, D., Origin of life: An explanation of what is needed for abiogenesis (or biopoiesis), creation.com/origin-of-life, 26 November 2013. Return to text.
- Trail, D. et al., The oxidation state of Hadean magmas and implications for early Earth’s atmosphere, Nature 480:79–82, 01 December 2011 | doi:10.1038/nature10655. Return to text.
- Sarfati, J., The Miller–Urey experiment revisited, creation.com/miller3, 15 March 2015. Return to text.