  The 18-cm radio lines of the OH radical were observed in comet 103P/Hartley 2
with the Nan\c{c}ay radio telescope in support to its flyby by the EPOXI
mission and to observations with the Herschel Space Observatory. The OH lines
were detected from 24 September to 15 December 2010. These observations are
used to estimate the gas expansion velocity within the coma to 0.83 \pm 0.08
km/s in October 2010. The water production increased steeply but progressively
before perihelion, and reached 1.9 \pm 0.3 X 10E28 s-1 just before the EPOXI
flyby.
