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We present results from a 3-year program of nightly brightness monitoring of the Q0957+561 gravitational lens system. Based upon 368 nights of data, we find from direct autocorrelation that the time delay is 404±26 days. We include a pair of illustrations showing the A and B brightness curves for our intensively sampled data; these make an interesting lecture/classroom demonstration of time delay.
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Schild et al. (1997) studied this question.
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