Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. No one is completely sure . The relative average abundance in our Solar System appears higher than can be made in the early universe , in stars , and even in typical supernova explosions . Pictured above is a computer-animated frame depicting two neutron stars spiraling in toward each other, just before they collide . Since neutron star collisions are also suggested as the origin of gamma-ray bursts , it is possible that you already own a souvenir from one of the most powerful explosions in the universe.
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