  A harmonic oscillator model in four dimensions is presented for the helium
atom to estimate the distance to the inner and outer electron from the nucleus,
the angle between electrons and the energy levels. The method is algebraic and
is not based on the choice of correct trial wave function. Three harmonic
oscillators and thus three quantum numbers are sufficient to describe the
two-electron system. We derive a simple formula for the energy in the general
case and in the special case of the Wannier Ridge. For a set of quantum numbers
the distance to the electrons and the angle between the electrons are uniquely
determined as the intersection between three surfaces. We show that the excited
states converge either towards ionization thresholds or towards extreme
parallel or antiparallel states and provide an estimate of the ground state
energy.
