International audienceGlobal maps of Jupiter’s atmospheric temperatures, gaseous composition and aerosol opacity are derived from a programme of 5–20 µm mid-infrared spectroscopic observations using the Texas Echelon Cross Echelle Spectrograph (TEXES) on NASA’s Infrared Telescope Facility (IRTF). Image cubes from December 2014 in eight spectral channels, with spectral resolutions of R ∼2000−12,000−12,000 and spatial resolutions of 2–4° latitude, are inverted to generate 3D maps of tropospheric and stratospheric temperatures, 2D maps of upper tropospheric aerosols, phosphine and ammonia, and 2D maps of stratospheric ethane and acetylene. The results are compared to a re-analysis of Cassini Composite Infrared Spectrometer (CIRS) observations acquired during Cassini’s closest approach to Jupiter in December 2000, demonstrating that this new archive of ground-based mapping spectroscopy can match and surpass the quality of previous investigations, and will permit future studies of Jupiter’s evolving atmosphere. The visibility of cool zones and warm belts varies from channel to channel, suggesting complex vertical variations from the radiatively-controlled upper troposphere to the convective mid-troposphere. We identify mid-infrared signatures of Jupiter’s 5-µm hotspots via simultaneous M, N and Q-band observations, which are interpreted as temperature and ammonia variations in the northern Equatorial Zone and on the edge of the North Equatorial Belt (NEB). Equatorial plumes enriched in NH3 gas are located south-east of NH3-desiccated ‘hotspots’ on the edge of the NEB. Comparison of the hotspot locations in several channels across the 5–20 µm range indicate that these anomalous regions tilt westward with altitude. Aerosols and PH3 are both enriched at the equator but are not co-located with the NH3 plumes. The equatorial temperature minimum and PH3/aerosol maxima have varied in amplitude over time, possibly as a result of periodic equatorial brightenings and the fresh updrafts of disequilibrium material. Temperate mid-latitudes display a correlation between mid-IR aerosol opacity and the white albedo features in visible light (i.e., zones). We find hemispheric asymmetries in the distribution of tropospheric PH3, stratospheric hydrocarbons and the 2D wind field (estimated via the thermal-wind equation) that suggest a differing efficiency of mechanical forcing (e.g., vertical mixing and wave propagation) between the two hemispheres that we argue is driven by dynamics rather than Jupiter’s small seasonal cycle. Jupiter’s stratosphere is notably warmer at northern mid-latitudes than in the south in both 2000 and 2014, although the latter can be largely attributed to strong thermal wave activity near 30°N that dominates the 2014 stratospheric maps and may be responsible for elevated C2H2 in the northern hemisphere. A vertically-variable pattern of temperature and windshear minima and maxima associated with Jupiter’s Quasi Quadrennial Oscillation (QQO) is observed at the equator in both datasets, although the contrasts wer...

We discuss the design and performance of TEXES, the Texas Echelon Cross Echelle Spectrograph. TEXES is a mid-infrared (5-25 µm) spectrograph with several operating modes: high-resolution, cross-dispersed with a resolving power of R = λ/δλ ≈ 100,000, 0.5% spectral coverage, and a ∼ 1.5 × 8 ′′ slit; medium-resolution long-slit, with R ≈ 15,000, 0.5% coverage, and a ∼ 1.5×45 ′′ slit; low-resolution long-slit, with δλ ≈ .004 µm, 0.25 µm coverage, and a ∼ 1.5 × 45 ′′ slit; and source acquisition imaging with 0.33 ′′ pixels and a 25 × 25 ′′ field of view on a 3 m telescope. TEXES has been used at the McDonald Observatory 2.7m and the IRTF 3m telescopes, and has proven to be both sensitive and versatile.Subject headings: infrared: general -instrumentation: spectrographs -techniques: spectroscopic Observatory (ISO) short wavelength spectrometer with R = λ/δλ ≈ 2000. SIRTF, with R ≈ 600 and much better sensitivity than can be achieved from the ground, will continue this study. However, neither of these spacecraft spectrometers was optimized for studies of narrow gas-phase lines.Mid-infrared ionic lines have been studied in a number of sources by several ground-based instruments, as well as by ISO. These lines provide information similar to that obtained from visible wavelength forbidden and recombination lines, but can be studied in much more obscured sources. With widths ≈ 10 − 100 km s −1 (the latter in external galaxies), these lines are best studied by instruments with R ∼ 10 4 . Our previous instrument, Irshell (Lacy et al. 1989), was optimized for the study of these lines. ISO greatly expanded on the earlier ground-based work, as will SIRTF, although the lower resolution on the space-based mid-IR spectrometers is insufficient for detailed kinematic studies.Less work has been done on molecular lines in the mid-infrared. In molecular clouds these lines have widths of only a few km s −1 , requiring R ≥ 100,000 for optimal sensitivity and to obtain kinematic information in line profiles. Although a few instruments have achieved such high resolution in the mid-infrared (heterodyne spectrometers, e.g. Mumma et al. 1982, and Fourier transform spectrometers, e.g. Ridgway & Brault 1984), the sensitivity of these instruments was sufficient for the study of only a few of the brightest objects in the sky. Considerable work has been done with ISO (e.g. Lahuis & van Dishoeck 2000) concentrating on the many lines of molecular Q-branches. Using Irshell, with R ≈ 10,000, we observed interstellar C 2 H 2 and CH 4 , as well as several other molecules, but could not resolve the individual lines except in regions of shocks or rapid outflows. As a result, we were limited to measurements of equivalent widths of often saturated lines. From this experience we concluded that whereas space-based spectrometers will improve on our observations of solid-state and ionic lines, at least in cases where high spatial resolution is not required, a high spectral resolution and high sensitivity ground-based (or airborne) spectrograph was required to fur...

Juno swoops around giant Jupiter Jupiter is the largest and most massive planet in our solar system. NASA's Juno spacecraft arrived at Jupiter on 4 July 2016 and made its first close pass on 27 August 2016. Bolton et al. present results from Juno's flight just above the cloud tops, including images of weather in the polar regions and measurements of the magnetic and gravitational fields. Juno also used microwaves to peer below the visible surface, spotting gas welling up from the deep interior. Connerney et al. measured Jupiter's aurorae and plasma environment, both as Juno approached the planet and during its first close orbit. Science , this issue p. 821 , p. 826

Observations made during the New Horizons flyby provide a detailed snapshot of the current state of Pluto's atmosphere. While the lower atmosphere (at altitudes <200 km) is consistent with ground-based stellar occultations, the upper atmosphere is much colder and more compact than indicated by pre-encounter models. Molecular nitrogen (N 2 ) dominates the atmosphere (at altitudes <1800 km or so), while methane (CH 4 ), acetylene (C 2 H 2 ), ethylene (C 2 H 4 ), and ethane (C 2 H 6 ) are abundant minor species, and likely feed the production of an extensive haze which encompasses Pluto. The cold upper atmosphere shuts off the anticipated enhanced-Jeans, hydrodynamic-like escape of Pluto's atmosphere to space. It is unclear whether the current state of Pluto's atmosphere is representative of its average state-over seasonal or geologic time scales.

1] Although of great interest for science and resource utilization, the Moon's permanently shadowed regions (PSRs) near each pole present difficult targets for remote sensing. The Lyman Alpha Mapping Project (LAMP) instrument on the Lunar Reconnaissance Orbiter (LRO) mission is able to map PSRs at far-ultraviolet (FUV) wavelengths using two faint sources of illumination from the night sky: the all-sky Ly a glow produced as interplanetary medium (IPM) H atoms scatter the Sun's Ly a emissions, and the much fainter source from UV-bright stars. The reflected light from these two sources produces only a few hundred events per second in the photon-counting LAMP instrument, so building maps with useful signal-to-noise (SNR) ratios requires the careful accumulation of the observations from thousands of individual LRO orbits. In this paper we present the first FUV albedo maps obtained by LAMP of the Moon's southern and northern polar regions. The results show that (1) most PSR regions are darker at all FUV wavelengths, consistent with their surface soils having much larger porosities than non-PSR regions (e.g., $70% compared to $40% or so), and (2) most PSRs are somewhat "redder" (i.e., more reflective at the longer FUV wavelengths) than non-PSR regions, consistent with the presence of $1-2% water frost at the surface. Citation: Gladstone, G. R., et al. (2012), Far-ultraviolet reflectance properties of the Moon's permanently shadowed regions,