Evidence of nearby supernovae affecting life on Earth

Abstract

Observations of open star clusters in the solar neighborhood are used to calculate local supernova (SN) rates for the past 510 million years (Myr). Peaks in the SN rates match passages of the Sun through periods of locally increased cluster formation which could be caused by spiral arms of the Galaxy. A statistical analysis indicates that the Solar System has experienced many large short-term increases in the flux of Galactic cosmic rays (GCR) from nearby supernovae. The hypothesis that a high GCR flux should coincide with cold conditions on the Earth is borne out by comparing the general geological record of climate over the past 510 million years with the fluctuating local SN rates. Surprisingly a simple combination of tectonics (long-term changes in sea level) and astrophysical activity (SN rates) largely accounts for the observed variations in marine biodiversity over the past 510 Myr. An inverse correspondence between SN rates and carbon dioxide (CO${}_2$) levels is discussed in terms of a possible drawdown of CO${}_2$ by enhanced bioproductivity in oceans that are better fertilized in cold conditions - a hypothesis that is not contradicted by data on the relative abundance of the heavy isotope of carbon, ${}^{13}$C.

21 pages, 22 figures

References in corpus (4)

• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• A connection between star formation activity and cosmic rays in the starburst galaxy M 82
• Spectrum of cosmic rays, produced in supernova remnants
• Obtaining the diffusion coefficient for cosmic ray propagation in the Galactic Centre Ridge through time-dependent simulations of their gamma-ray emission

Cited by in corpus (4)

• How much has the Sun influenced Northern Hemisphere temperature trends? An ongoing debate
• On Earth's habitability over the Sun's main-sequence history: joint influence of space weather and Earth's magnetic field evolution
• Supernova origin of cosmic rays from a gamma-ray signal in the Constellation III region of the Large Magellanic Cloud
• Setting the Stage for Habitable Planets