Publication Date:
2017-10-21
Description:
Jupiter's tropospheric ammonia (NH 3 ) abundance is studied using spatially-resolved 5- μ m observations from CRIRES, a high resolution spectrometer at the European Southern Observatory's Very Large Telescope. The high resolving power (R=96,000) allows the line shapes of three NH 3 absorption features to be resolved. We find that within the 1–4 bar pressure range, the NH 3 abundance decreases with altitude. The instrument slit was aligned north-south along Jupiter's central meridian, allowing us to search for latitudinal variability. There is considerable uncertainty in the large-scale latitudinal variability, as the increase in cloud opacity in zones compared to belts can mask absorption features. However, we do find evidence for a strong NH 3 enhancement at 4–6° N, consistent with a localised ‘ammonia plume’ on the southern edge of Jupiter's North Equatorial Belt.
Print ISSN:
0094-8276
Electronic ISSN:
1944-8007
Topics:
Geosciences
,
Physics
Permalink
