This is a series of four images of the K fragment
in the 7.7 micron methane region at a resolution of 9000 using KEGS on
the Kuiper Airborne Observatory. In each image, wavelength increases from
7.685 to 7.722 microns from left to right. The y axis represents a long-slit
spatial cut through Jupiter. From top to bottom, these images were taken
at UT= 10:28, 10:39, 10:53, and 11:04. The fireball is clearly evident
in the second image; the methane emission increased by about a factor
of 25 compared to the pre-impact emission (top image).
The spatial scale is 4"/pixel. Our point spread function
is ~7" due to motion of the airborne telescope. The brightness contours
range from 1 to 43 arbitrary units in steps of 2.
The 7.7 micron region is a sensitive thermometer
of the jovian stratosphere sounding levels between 1 microbar and 10 millibars,
far above the visible clouds. This region is totally blocked by methane
in the Earth's atmosphere -it cannot be observed from ground-based telescopes.
The KAO is the only observatory capable of investigating this spectral
region.
The high spectral resolution of the KEGS instrument
reveals individual emission lines of C-12 and C-13 CH4. At least 2 unknown
emission lines were observed in the spectrum of the fireball. These may
be due to high excitation states of CH4 or due to a different species
altogether.
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