The biblical record of patriarchs who lived 900+ years has raised questions and doubts for centuries. In the context of current life expectancy (which places me on the brink of “senior citizen” status), some Bible readers assume the “years” in the Genesis 5 and 11 chronologies must have been shorter than the familiar 12-month whirl around the Sun. But there’s nothing in the text or in other ancient records to support such a view and much to contradict it.
One way to approach the question is to ask, Why can’t people live that long today? What limits human life spans to just a fraction of the 900 years? And how might that answer help explain—and defend—the ancient text?
In my own and others’ writings, the Vela supernova (a massive stellar explosion that occurred early in the human era) has been identified as the possible culprit. It seems this event may be at least partly responsible for the cosmic radiation that keeps people from living longer than 120 years or so. In recent months, however, a new and much more likely suspect has been identified.
First, some background. Deadly, cancer-causing (life-shortening) radiation comes from two main sources: 1) the decay of radioactive materials in Earth’s crust, and 2) massive stellar explosions (supernovae) within the Milky Way Galaxy. Cosmic radiation from supernovae (and their remnants) showers the Earth all the time. Most of that radiation is benign and fairly constant, just electrons and protons moving at less-than-dangerous velocities. But some—such as the electron-stripped atoms of oxygen and iron moving at hyper-fast velocities—can do major damage to living things.
Since 1996 Anatoly Erlykin and Arnold Wolfendale have been studying cosmic radiation’s particle energy spectrum—in particular, the high end (above a quadrillion electron volts per nucleon). They have found two peaks in the spectra, protruding high above the background. These peaks, they say, are the signature of a single, major event—a local, recent supernova blast. In other words, the thousands of supernova remnants scattered throughout the Milky Way Galaxy account for the relatively constant radiation background, but the two peaks tell of a local, recent supernova, the shock waves of which would have increased the velocities of oxygen and iron nuclei, turning them into killer radiation.
Initially, Erlykin and Wolfendale loosely identified this supernova as one closer than 3,000 light years and more recent than 100,000 years ago. These features suggested the Vela supernova (distance = 936 light years; eruption date = 20,000-30,000 years ago) as a prime possibility. With improved data, however, Erlykin and Wolfendale have been able to make a more positive identification. This particular supernova occurred so close to Earth that our solar system likely resides just inside the shell of its remnant. That remnant itself, they point out, occupies a significant portion (up to 40 degrees) of the sky—so vastly spread out that astronomers would have had great difficulty distinguishing it from the background.
This local, recent supernova may be a key to explaining the change in life spans from the Genesis patriarchs’ era to the present. Early humans, living before the supernova event, would have been exposed to a much lower incidence of high-energy, heavy-nuclei cosmic radiation. Consequently, they would have faced a lesser risk of cancer and cell damage. And if they lived in the Mesopotamian Plain, they would have experienced less exposure to the radiation that comes from igneous rocks (assuming they had not yet exploited gravel, granite, concrete, asphalt, etc. as building materials).
Further implication of this supernova’s involvement in reducing life spans comes from the pattern of that reduction. It can be reasonably inferred from Genesis 9:28 and 11:10-26 that life span reduction did not occur all at once; rather, it occurred somewhat gradually, following the curve scientists would predict for the increasing impact of the deadly rays.
With certain minor biochemical adjustments (such as increased telomerase activity) and a low-calorie, low-oxidant, high-antioxidant diet (such as the pre-Flood humans were instructed to eat), people living before the time of that supernova could possibly have lived several hundred years, just as the biblical text says.
A. D. Erlykin and A. W. Wolfendale, “A Single Source of Cosmic Rays in the Range 1015 – 1016 eV,” Journal of Physics G: Nuclear and Particle Physics 23 (1997): 979-89; A. D. Erlykin and A. W. Wolfendale, “High-Energy Cosmic Ray Mass Spectroscopy. II. Masses in the Range 1014 – 1017 eV,” Astroparticle Physics 7 (1997): 203-11; A. D. Erlykin and A. W. Wolfendale, “’Fine Structure’ in the Energy Spectrum, and Changes in the Mass Composition, of Cosmic Rays in the Energy Range 0.3 – 10 PeV,” Astronomy and Astrophysics Letters 350 (1999): L1-L4; A. D. Erlykin and A. W. Wolfendale, “The Origin of PeV Cosmic Rays,” Astronomy and Astrophysics Letters 356 (2000): L63-L65; A. D. Erlykin and A. W. Wolfendale, “Structure in the Cosmic Ray Spectrum: an Update,” Journal of Physics G: Nuclear and Particle Physics 27 (2001): 1005-30; A. D. Erlykin and A. W. Wolfendale, “High-Energy Cosmic Gamma Rays from the ‘Single Source,’” Journal of Physics G: Nuclear and Particle Physics 29 (2003): 709-18; A. D. Erlykin and A. W. Wolfendale, “Spectral Features and Masses in the PeV Region,” Nuclear Physics B—Proceedings Supplements 122 (2003): 209-12.
 B. Aschenback, R. Egger, and J. Trumpler, “Discovery of Explosion Fragments Outside the Vela Supernova Remnant Shock-Wave Boundary,” Nature 373(1995): 598; A. G. Lyne, R. S. Pritchard, F. Graham-Smith, and F. Camilo, “Very Low Braking Index for the Vela Supernova,” Nature 381 (1996): 497-98.
 Fazale R. Rana, Hugh Ross, and Richard Deem, “Long Life Spans: ‘Adam Lived 930 Years and Then He Died,’” Facts for Faith 5 (Q1 2001), 18-27.