Albert Einstein’s theory of gravitational redshift was proven after a telescope in Chile observed a black hole.
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The Summer Olympic Games opening ceremony was held outdoors for the first time ever.
Niger President Mohamed Bazoum was removed from office by a military coup.
President Donald Trump banned transgender persons from joining the US military.
Platform diver Tom Daley won his first Olympic gold medal in men's synchronized diving, 13 years after his first Olympic games.
In one day, Facebook lost $120 billion in value on the stock market.