A third of the human population sneezes when they look at the Sun. Light can signal the ocular nerve near the sinuses and triggers a sneeze.
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An international team of astronomers has spotted the farthest known gravitational lens and, as Albert Einstein predicted, it is a galaxy that deflects and intensifies the light of a much further object.
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It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
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