It was the wrong speed. His measurement of the period was off by a few seconds and he didn't have the exact length of 2 A.U. He did prove it was fixed and not infinite--like Galileo stated.
It was the Danish astronomer, Olaus Roemer, who, in 1676, first successfully measured the speed of light. His method was based on observations of the eclipses of the moons of Jupiter (by Jupiter).
Don Roemer's birth name is Donald Culligan Roemer.
Sarah Roemer's birth name is Sarah Christine Roemer.
Anton Roemer's birth name is Antonie Gerardus Joseph Roemer.
Emile Roemer's birth name is Emile Gerardus Maria Roemer.
Ruth Roemer was born in 1916.
Roemer Visscher was born in 1547.
Elizabeth Roemer was born in 1929.
Jean Roemer was born in 1815.
Jean Roemer died in 1892.
Roemer Lievaart is 194 cm.
Michael Roemer was born in 1928.