The remote-sensing projects described above all rely on sunlight
scattered from particles in the planets' atmospheres. But on Jupiter, we
have also been studying thermal infrared and radio wavelength light,
heat energy that is radiatively escaping from the planet.
Observations with the VLA show intricately detailed bright and dark
patterns at different wavelengths, revealing spatial variation in the
amount of ammonia gas present. Ammonia acts as a tracer of vertical
motions, so the brightness patterns correspond to upwelling and
downwelling due to convection, waves, jets, and turbulence. Juno's
microwave radiometer will use a similar approach, but at a unique
vantage point inside Jupiter's radiation belts. VLA science is performed
as a collarboration with Prof. Imke de Pater.
High-resolution spectrometers, operating in the 5-μm region of the
thermal infrared spectrum, are also able to sense variations in ammonia
concentration. We use facilities at the NASA IRTF and Keck telescopes to
measure individual molecular line shapes, revealing water vapor,
phosphine, and cloud distributions as well as ammonia. High-resolution
spectroscopic studies are performed as a collarboration with Gordon
Bjoraker at NASA Goddard, funded by NASA.