|
C/2020 F3 (NEOWISE) Spatial Distribution of Spectral Components

ATIK 428 camera
Celestron C11 SCT 280mm aperture f5.5
Spectral cross sections across the coma and the tail 4 arc min from the centre of the coma. (click for full size image)
The relative intensity of the main spectral components, Dust, Na, CN, (C2 in coma) (CO+ in tail) are plotted relative to the central line through coma and tail.
The CN and Sodium components are seen in both coma and tail but the C2 component which dominates the coma emission spectrum is absent in the tail, replaced by the CO+ component.
The spatial distributions are significantly different for the various components. In particular the sodium emission in the coma is confined to a narrow central region but the CN component is widespread in both the coma and tail. The Sodium distribution in the tail is skewed anticlockwise relative to the dust, consistent with the presence of a separate sodium tail.