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Nova Cygni 1992 (NC92), the brightest northern hemisphere nova in nearly 20 years, has provided astronomers with the first detailed record of the temporal development of a nova explosion on an Oxygen-Neon-Magnesium (ONeMg) white dwarf (WD). Theoretical models of thermonuclear runaways suggest that these "neon novae" may be important sources of Neon 22, Sodium 22, and Aluminum 26, and that they may produce enhanced amounts of magnesium and silicon as well. Abundances of some of these isotopes in meteorites suggest that ejecta from neon nova eruptions may have contaminated the ISM cloud from which the primitive solar system formed. Infrared photometric and spectroscopic techniques for determining the abundances of elements in the nova ejecta will be reviewed. These include observations of thermal-infrared emission from solid grains that condense in the expanding ejecta, and measurements of the strengths of near infrared coronal emission lines that arise in the gas phase of the ejecta. Neon abundances can be estimated using the 7.6 micron line of [Ne VI] and the 12.8 micron line of [Ne II]. Recent results on NC 92 and QU Vul, the archetypal neon nova, will be emphasized. The temporal development of infrared photometric light curves as a tool for distinguishing between CO and ONeMg novae will be discussed.
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