Did Earth Get Its Water from Meteor Squirt Guns?
You can’t just fire bullets at pumice and claim that Earth got its oceans that way.
Talk about weird science. Two guys at Brown University went to a shooting range to figure out how Earth got its water. But is their theory all wet?
First, they realize that explaining that has been difficult. From their paper in Science Advances, R. Terik Daly and Peter H. Schultz say,
The timing of volatile delivery to the inner solar system continues to be debated. Some have argued that the terrestrial planets accreted dry and later gained volatiles as part of the “late veneer”. Recent Ru isotopic data, however, imply that the late veneer was not the primary source of volatiles on Earth. Moreover, data from angrites and eucrites point to the accretion of water in the inner solar system within the first few million years of solar system history. Isotopic evidence also indicates that carbonaceous chondrite (CC)–like impactors delivered much of the volatiles in the inner solar system. However, the actual mechanisms that trap this water remain poorly constrained.
Creationists say that Earth had its water from the beginning, but of course, they are not allowed into the debate, because they (with their peer-reviewed journals) are discriminated against as a class. Faced with an unending controversy, the two materialists went to a gun range to do some target practice. Using bullets of antigorite, a serpentine mineral they consider a “proxy” for carbonaceous chondrites (a common type of meteor), they shot at pumice, which they consider a “proxy” for the early crust. What did they get? Fragments of breccia (broken pieces of stuff), and some pieces of glass from the impact melt. If the CC’s came with any H2O, they figure that about 30% of it might have survived in the glass. Here it is in jargonese:
Dynamical models and observational evidence indicate that water-rich asteroids and comets deliver water to objects throughout the solar system, but the mechanisms by which this water is captured have been unclear. New experiments reveal that impact melts and breccias capture up to 30% of the water carried by carbonaceous chondrite–like projectiles under impact conditions typical of the main asteroid belt impact and the early phases of planet formation. This impactor-derived water resides in two distinct reservoirs: in impact melts and projectile survivors. Impact melt hosts the bulk of the delivered water. Entrapment of water within impact glasses and melt-bearing breccias is therefore a plausible source of hydration features associated with craters on the Moon and elsewhere in the solar system and likely contributed to the early accretion of water during planet formation.
We hope they had fun shooting, because logically, they can’t use the results of target practice to extrapolate to the formation of the Earth and its oceans. It might make them feel good to be published for their recreational sport, but proxies are not realities. Theory-laden proxies—relying on assumptions as they do—can mislead. And tiny bits of stuff under artificial conditions may have nothing to do with planetary-sized events of the unobservable past. Anyway, off they went from the range, telling the story of How the Earth Got Its Water.
The fact that the amorphous, glassy component—not projectile survivors—constitutes the primary reservoir for impact-delivered water is critical for extrapolating these experiments. Impact melt production increases with impact speed. If impact melt derived primarily from the target successfully traps water during collisions among planetary bodies (as it does in experiments), then higher-speed impacts may still deliver significant quantities of water.
It may, or it may not. That’s a big ‘If.’ Did they quantify if target practice by blind shooters could deliver 1.333 billion cubic kilometers of water to the Earth? No. Did they find corresponding relative amounts of water on the moon, Venus, Mercury and Mars? No. Did they determine if the deuterium content of CC water corresponds to the amount in ocean water? (That’s what shot down the comet-water-balloon theory, 22 March 2017.) No. Did they calculate the volume of CC’s that would have had to hit Earth to contribute to the present water content of the Water Planet? No. Did they determine if that’s how the water 100 miles under the crust got there? No. Did they critique the accretion theory of planet formation? No. Did they read Genesis 1? No.
But because their theory is 100% naturalistic, purposeless, aimless, and unverifiable, it got published by the AAAS. Pretty good reward for a day at the shooting range.
Once upon a time, blind shooters squirted water at a dry planet. From that water, life emerged, and evolved into scientists who tell just-so stories. Isn’t science wonderful.
Remember to get Dr Henry Richter’s book Spacecraft Earth to learn about all the design evidences for Earth’s habitability. The evidence convinced this spacecraft pioneer (PhD, Caltech) that Earth was intelligently designed to be habitable (Isaiah 45:18). Later, the Bible convinced him that the Designer was God, who was not silent, but left us a “Guide for Passengers” in his revealed Word.