Aller will use the Hamilton echelle spectrograph at Lick Observatory to obtain spectra of planetary nebulae at high dispersion and with a broad wavelength coverage. The goal is to measure the intensities of spectral lines that previously were too faint and/or too blended with other lines. This should yield accurate chemical compositions for a small sample of bright nebulae for which much complementary information has already been obtained in other wavelength ranges. Planetary nebulae are gaseous nebulae that have been expelled from aging stars. The nebulae contain the elements generated within the stars and thus inform us of stellar nucleosynthesis during an important but otherwise inaccessible phase of a star's life. Aller will use a new spectrograph at Lick Observatory to observe selected planetary nebulae, specifically to measure accurately much fainter spectrum lines than has been possible heretofore. This will yield greatly improved stellar chemical abundances and, simultaneously, much new atomic information not obtainable in the laboratory.
