Maximum number of general-position points with mutual rational distances?

Question

Richard Guy has shown that there are six points in the plane—no three collinear, no four cocircular—such that all interpoint distances are rational.

Guy, Richard. Unsolved Problems in Number Theory. Vol. 1. Springer, 2004. D20. Six general points at rational distances. p.185ff:

My question is:

Q. Is it known that six is the maximum possible? Or have examples been found in the intervening decade that supersede Guy's result?

Update. This question is essentially a duplicate of "Integer-distance sets." Apologies.

Didn't you already ask this, mathoverflow.net/questions/136925/integer-distance-sets — Gerry Myerson, Commented Oct 5, 2014 at 4:46
@GerryMyerson: Whoops, you are right, I already asked a version of this question---Sorry! But now I cannot delete it. — Joseph O'Rourke, Commented Oct 5, 2014 at 11:44

Gerry Myerson · Accepted Answer · 2014-10-05 04:43:15Z

6

There is a heptagon with all integer distances here.

answered Oct 5, 2014 at 4:43

Gerry Myerson

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