  A novel low-energy ($\sim$few keV) neutrino-oscillation experiment NOSTOS,
combining a strong tritium source and a high pressure spherical Time Projection
Chamber (TPC) detector 10 m in radius has been recently proposed. The
oscillation of neutrinos of such energies occurs within the size of the
detector itself, potentially allowing for a very precise (and rather
systematics-free) measure of the oscillation parameters, in particular, of the
smaller mixing angle $\theta_{13}$, which value could be determined for the
first time. This detector could also be sensitive to the neutrino magnetic
moment and be capable of accurately measure the Weinberg angle at low energy.
The same apparatus, filled with high pressure Xenon, exhibits a high
sensitivity as a Super Nova neutrino detector with extra galactic sensitivity.
The outstanding benefits of the new concept of the spherical TPC will be
presented, as well as the issues to be demonstrated in the near future by an
ongoing R&D. The very first results of small prototype in operation in Saclay
are shown.
