When will Mars, Jupiter and Saturn be aligned the next time?

Answer 1

On Mar 28, 2020, the 3 planets (and Pluto) will all be within 7 degrees of one another.
http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=499&vbody=399&month=3&day=28&year=2020&hour=00&minute=00&fovmul=1&rfov=10&bfov=20&brite=1

How close of an alignment are you wanting?

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