The spin-1 Heisenberg antiferromagnetic (HAFM) chain is a canonical model system in quantum magnetism. The existence of the Haldane gap to the lowest energy excitations has been demonstrated in many experimental realisations. However, the nature of the multimagnon continua is much less clear. We propose to fully measure the one- and multi-magnon spectra as a function of wave vector along the chains and frequency, S(q, w), in the classic S=1 HAFM chain compound, NENP, and compare the results with calculations for the multimagnon continua in the low temperature limit. We then propose to investigate the very recent prediction of thermally induced magnon scattering below the one-magnon dispersion.