Reasons to Believe

Testing Assumptions Confirm Antiquity of Solar System

“[Science] is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. ... The obvious is sometimes false; the unexpected is sometimes true.”

 — Carl Sagan, Cosmos, pg 277.

One underlying principle that enables the scientific enterprise to discover the truth is the commitment that everything must be tested. This principle comes directly from the Bible (see 1 Thessalonians 5:21). Because every belief and explanation rests on assumptions, the confidence in those beliefs and explanations grows as tests confirm the assumptions. Tests that falsify assumptions provide avenues to provide even better explanations. Recent exploration of meteorites demonstrates how this process works in practice.

Scientists use the abundances of various radioactive isotopes to date the origin of the solar system. In particular, two isotopes of uranium (U)—one with 235 nucleons, the other with 238—decay to two different isotopes of lead (Pb). Measuring decay rates of the two uranium isotopes and the quantities of the lead isotopes measured in particular components of a meteorite allows scientists to calculate the age of the meteorite component. This dating process for the age of the solar system relies on some assumptions. The meteor component must have formed in the earliest parts of the solar system. Calcium aluminum inclusions (CAIs) meet this criterion. Another assumption is that the ratio of the radioactive uranium isotopes was constant throughout the early solar system.

Recent research led by scientists at Arizona State University demonstrated that this last assumption is false. A detailed study of uranium in numerous CAIs from the Allende meteorite shows small variations (less than half a percent) in the ratios of the radioactive uranium isotopes. Variations of this size lead to errors in age measurements of a few million years—a small amount compared to the 4.57 billion year ages determined for the CAIs.

While tests show the “constant-uranium-isotope-fraction” assumption wrong, two points need emphasizing. First, the errors introduced by the assumption are small and do not significantly affect the dates calculated using the “wrong” assumption. In fact, the uranium variations provide a tool to explore the environment in the early solar system in more detail. In other words, testing this assumption strengthened confidence in the ages derived and opened avenues of research that will lead to a better understanding of how the solar system formed. Second, it would be incorrect to conclude that this “failed” assumption casts doubts on the legitimacy of radioisotope dating techniques.

These results put at least one part of RTB’s cosmic creation model on firmer footing, namely that the solar system formed around 4.5 billion years ago. It also affirms that the biblical mandate to test everything and hold on to the good leads to a better understanding of the truth.

Subjects: Scientific Evidence for an Old Earth

Dr. Jeff Zweerink

While many Christians and non-Christians see faith and science as in perpetual conflict, I find they integrate well. They operate by the same principles and are committed to discovering foundational truths. Read more about Dr. Jeff Zweerink.