The scanner observations of periodic Comet Halley (1982i) have been presented in the wavelength region XA3200-7000 w for three nights during pre-perihelion period. Emission features due to NH, CN, CH, C,, C,, and NH, molecules have been identified. The abundances and production rates of CN and C, species have been estimated.

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Spectrum scans have been obtained of the head of Comet Austin on six nights at heliocentric distances (r) from 0.70 to 0.87AU. The useful spectral region is h&330-750nm. Strong emission features of CN (388nm) and Swan band sequence of C, (474, 516, and 563nm) were identified. Weak emission features of CH + C,(436 nm), C,(600nm), CN(420 nm) and CH + C,(405 nm) have also been found present. There is a change in the ratio of CN(388nm) to C,(516 nm) emission strength with increasing heliocentric distance. An estimate of the CN and C, abundances has been made and their production rates have been derived. The continuum of the comet is strongly reddened with reference to Sun. The continuum matches the scattered continuum of solar radiation according to hZ law (Mie scattering) closely.

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