Northwestern Univ. research reported in the English newspaper, The Telegraph, describes how their is a light flash when sperm impregnates a human egg. The following pictures shows the “flash” in the 0.40 sec. frame.
Scientists had seen the phenomenon occur in other animals but it is the first time is has been also shown to happen in humans. Not only is it an incredible spectacle, highlighting the very moment that a new life begins, the size of the flash can be used to determine the quality of the fertilized egg.
The researchers note that the bright flash occurs because when sperm enters an egg it leads to a surge of calcium which triggers the release of zinc from the egg. As the zinc shoots out, it binds to small molecules which emit a fluorescence which can be picked up by camera microscopes.
Amazing development: seeing the start of human life.