The majority of major share market movements occur without any particular news hitting the market.
Studies of the 50 largest share market movements in the US stock market between 1946 and 1987 found that the majority of them could not be explained by news. That includes the 1987 share market crash. In October 1987, shares fell by 20% in one day for no obvious reason.
David Romer explained these booms and busts, including the 1987 share market crash in two ways: investor uncertainty about the quality of other investors’ information; and dispersion of information and small costs to trading:
Asset prices can change because initially the market does an imperfect job of revealing the relevant information possessed by different investors and because developments within the market can then somehow cause more of that information to be revealed
Either of these models are perfectly plausible. Investors learn from each other through trading and improve their estimations of the value of various shares.
Utopia, you are standing in it! 
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