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Our goal was to characterize the distant gaseous and dust activity of cometC\2012 S1 (ISON), inbound, from observations of H2O, CO and the dust coma inthe far-infrared and submillimeter domains. In this paper, we reportobservations undertaken with the Herschel Space Observatory on 8 & 13 March2013 (rh = 4.54 - 4.47AU) and with the 30m telescope of Institut deRadioastronomie Millim\'etrique (IRAM) in March and April 2013 (rh = 4.45 -4.18 AU). The HIFI instrument aboard Herschel was used to observe the H$_{2}$O$1_{10}-1_{01}$ line at 557 GHz, whereas images of the dust coma at 70 and 160{\mu}m were acquired with the PACS instrument. Spectra acquired at the IRAM 30mtelescope cover the CO J(2-1) line at 230.5 GHz. The spectral observations wereanalysed with excitation and radiative transfer models. A model of dust thermalemission taking into account a range of dust sizes is used to analyse the PACSmaps. While H$_{2}$O was not detected in our 8 March 2013 observation, wederive a sensitive 3 $\sigma$ upper limit of QH$_{2}$O < 3.5 x 10$^{26}$molecules/s for this date. A marginal 3.2 $\sigma$ detection of CO is found,corresponding to a CO production rate of QCO = 3.5 x 10$^{27}$ molecules/s. TheHerschel PACS measurements show a clear detection of the coma and tail in boththe 70 {\mu}m and 160 {\mu}m maps. Under the assumption of a 2 km radiusnucleus, we infer dust production rates in the range 10 - 13 kg/s or 40 - 70kg/s depending on whether a low or high gaseous activity from the nucleussurface is assumed. We constrain the size distribution of the emitted dust bycomparing PACS 70 and 160 {\mu}m data, and considering optical data. Sizeindices between -4 and -3.6 are suggested. The morphology of the tail observedon 70 {\mu}m images can be explained by the presence of grains with ages olderthan 60 days.

Herschel and IRAM-30m Observations of Comet C/2012 S1 (ISON) at 4.5 AU from the Sun