  The Stellar Observation Network Group (SONG) is an initiative to build a
worldwide network of 1m telescopes with highprecision radial-velocity
spectrographs. Here we analyse the first radial-velocity time series of a
red-giant star measured by the SONG telescope at Tenerife. The asteroseismic
results demonstrate a major increase in the achievable precision of the
parameters for redgiant stars obtainable from ground-based observations.
Reliable tests of the validity of these results are needed, however, before the
accuracy of the parameters can be trusted.
  We analyse the first SONG time series for the star 46 LMi, which has a
precise parallax and an angular diameter measured from interferometry, and
therefore a good determination of the stellar radius. We use asteroseismic
scaling relations to obtain an accurate mass, and modelling to determine the
age.
  A 55-day time series of high-resolution, high S/N spectra were obtained with
the first SONG telescope. We derive the asteroseismic parameters by analysing
the power spectrum. To give a best guess on the large separation of modes in
the power spectrum, we have applied a new method which uses the scaling of
Kepler red-giant stars to 46 LMi.
  Several methods have been applied: classical estimates, seismic methods using
the observed time series, and model calculations to derive the fundamental
parameters of 46 LMi. Parameters determined using the different methods are
consistent within the uncertainties. We find the following values for the mass
M (scaling), radius R (classical), age (modelling), and surface gravity
(combining mass and radius): M = 1.09 +- 0.04Msun, R = 7.95 +- 0.11 Rsun, age t
= 8.2 +- 1.9Gy, and log g = 2.674 +- 0.013.
