Medical doctors say if you live long enough you'll probably get cancer. Cancer is one reason why none of us can live much beyond 120 years.1 How is it possible, then, that humans (before Noah) could have lived 900 years or more, as the Bible says? Reduced exposure to cancer risk factors may provide at least a partial answer.
One major cancer risk is radiation. The deadliest radiation comes from cosmic rays and the decay of radioactive isotopes in Earth's crust. Crustal components that pose the greatest risk are igneous rocks. Avoidance of such rocks reduces dangerous exposure. According to the Bible, humanity's habitat before the Genesis Flood was limited to the Mesopotamian Plain, where igneous rocks are rare and the exploitation of igneous material (concrete, asphalt, granite, etc.) for building had not yet developed.
Cancer-causing cosmic radiation comes mostly from supernova remnants-thousands of them scattered throughout the disk of our galaxy. Electrons and protons make up most of this radiation, which constantly showers the Earth. But, as two astronomers recently discovered, there's more to the picture.
Since 1996 Anatoly Erlykin and Arnold Wolfendale have studied the particle energy spectrum of cosmic ray showers, focusing on extremely high-energy particles (above a quadrillion electron volts per nucleon).2 Their research has revealed two peaks in the radiation spectra, peaks identified with oxygen and iron nuclei. Such features, they claim, are the signature of one local, recent supernova.3 This massive nearby stellar explosion accelerated the nuclei of oxygen and iron in its shock waves.
Initially Erlykin and Wolfendale estimated that this particular supernova occurred within 3,000 light years of Earth and within the last 100,000 years.4 These rough limits made the Vela supernova (distance = 936 light years5; eruption date = 20,000-30,000 years ago6) a likely candidate. However, improved data has refined their view. Erlykin and Wolfendale now believe this supernova occurred so nearby that the solar system resides just inside the shell of its remnant.7 The remnant, they point out, occupies as much as 40 degrees of the sky and thus would be very difficult for any astronomer to distinguish from the galactic cosmic ray background.8
The local, recent supernova event that Erlykin and Wolfendale have identified may help explain the long life spans of the first humans-and the subsequent shortening of life spans. Humans living before such an event would have been exposed to a much lower incidence of the high-energy, heavy-nuclei cosmic radiation most clearly associated with cell damage and cancer. Given this lower radiation environment, the Creator could have granted early people a higher level of telomerase activity (a mechanism that maintains chromosome length and thereby permits a longer maximum life span but, under current radiation conditions, allows more cancers to grow). This higher telomerase activity in concert with other slight biochemical adjustments9, combined with a just-right diet (low calorie, low oxidant, high antioxidant)10 and the avoidance of igneous rocks, may be what allowed humans in the era before the Genesis Flood to live much longer than people since then, even by as much as 800 years.