| Spectra of the warm dust emission in a
2" x 1" wide slit centered on the coma's intensity peak. A strong
8 - 12 micron silicate emission feature is visible on each date,
and a narrower bump near 11.2 microns is due to crystalline
olivine grains. The curves drawn through the endpoints
indicate the approximate underlying continuum emission.
Structure near 9.5 microns is due to improper cancellation
of telluric ozone absorbtion while dividing by the standard star
spectrum. |
The 6 August spectrum of Hale - Bopp at r = 3.53 AU
after dividing by a 188 K blackbody (solid line), showing the relative
emissivity across the silicate feature. For comparison, a spectrum of comet
Levy taken at r = 1.54 AU and divided by a 266 K blackbody is also plotted
(dashed line). |
