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Supernova nucleosynthesis is the nucleosynthesis of chemical elements in supernova explosions.. In sufficiently massive stars, the nucleosynthesis by fusion of lighter elements into heavier ones occurs during sequential hydrostatic burning processes called helium burning, carbon burning, oxygen burning, and silicon burning, in which the byproducts of one nuclear fuel become, after ...
Artist's conception of a white dwarf, right, accreting hydrogen from the Roche lobe of its larger companion star A nova (pl. novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", Latin for "new") that slowly fades over weeks or months.
The first direct proof that nucleosynthesis occurs in stars was the astronomical observation that interstellar gas has become enriched with heavy elements as time passed. As a result, stars that were born from it late in the galaxy, formed with much higher initial heavy element abundances than those that had formed earlier.
However, most of the nucleosynthesis in the mass range A = 28–56 (from silicon to nickel) is actually caused by the upper layers of the star collapsing onto the core, creating a compressional shock wave rebounding outward. The shock front briefly raises temperatures by roughly 50%, thereby causing furious burning for about a second.
The heavy elements are produced by: nuclear fusion for nuclei up to 34 S; silicon photodisintegration rearrangement and quasiequilibrium during silicon burning for nuclei between 36 Ar and 56 Ni; and rapid capture of neutrons during the supernova's collapse for elements heavier than iron.
While heavy metals can be naturally excreted by the body through sweat and urine, if they are consumed in high amounts they can accumulate in the body and damage major organs.
Details of the pre-nova moments may help scientists better judge the quality of Type Ia supernovae as standard candles, which is an important link in the argument for dark energy. [ 46 ] In July 2019, the Hubble Space Telescope took three images of a Type Ia supernova through a gravitational lens .
Before you cozy up on the couch with a mug of your favorite hot chocolate, you might want to consider Consumer Report's latest list of powder mixes that contain high levels of metal.