References of "Miller, S"
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See detailSimultaneous Cassini VIMS and UVIS observations of Saturn's southern aurora
Melin, H.; Stallard, T.; Miller, S. et al

Conference (2012)

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See detailSaturn's aurora as viewed by Cassini VIMS
Melin, H.; Stallard, T.; Badman, S. V. et al

Conference (2011, December 01)

The stunning views of the kronian aurora captured by the Visual and Infrared Imaging Spectrograph (VIMS) onboard the Cassini spacecraft continues to provide crucial observations of the fervent interaction ... [more ▼]

The stunning views of the kronian aurora captured by the Visual and Infrared Imaging Spectrograph (VIMS) onboard the Cassini spacecraft continues to provide crucial observations of the fervent interaction between the upper atmosphere and the magnetosphere of Saturn. Here, we present recent findings of VIMS auroral research, which includes both statistical studies and case studies of auroral events and morphology. In addition to stand-alone observations, there is a small subset of VIMS observations during which UVIS was also acquiring data. These observations enable the comparison between observations of H, H2 in the ultraviolet and H3+ in the infrared that are both spatially overlapping and temporally simultaneous. Whilst emission tends to coincide for these three species on the main oval, there are significant differences both pole-ward and equator-ward, such that observations of H and H2 is generally a poor proxy for emissions of H3+. VIMS is sensitive to infrared thermal emission from the H3+ molecule, which is formed very efficiently via the ionisation of H2. Therefore, the morphology of H3+ emission becomes a tracer of energy injected into the upper atmosphere - the most striking of which is auroral particle precipitation. [less ▲]

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See detailSimultaneous Cassini VIMS and UVIS observations of Saturn's southern aurora
Melin, H.; Stallard, T.; Miller, S. et al

in EPSC-DPS Joint Meeting 2011 (2011, October 01)

Here, temporally simultaneous and spatially overlapping Cassini VIMS and UVIS observations of Saturn's southern aurora are presented. The pointing is fixed at a constant local time of 04:55, covering ... [more ▼]

Here, temporally simultaneous and spatially overlapping Cassini VIMS and UVIS observations of Saturn's southern aurora are presented. The pointing is fixed at a constant local time of 04:55, covering latitudes between 64°S and 82°S and longitudes between 127° and 186°. The spatial resolution is high, with 1 mrad covering ˜300 km, such that only a small part of the pre-dawn aurora is observed. Ultraviolet auroral H and H2 emissions from UVIS are compared to infrared H+3 emission from VIMS. The auroral emission is structured into three arcs - H, H2 and H+3 are morphologically identical in the bright main auroral oval (˜73°S), but there is an equatorward arc that is seen predominantly in H (˜70°S), and a poleward arc (˜74°S) that is seen mainly in H2 and H+3 . These observations indicate that, for the main auroral oval, the UV emission is a good proxy for the infrared H+3 morphology (and vice versa), but for emission either poleward or equatorward this is no longer true. Hence, given the highly dynamic nature of the aurora of Saturn, simultaneous UV/IR observations are crucial for completing the picture of how the atmosphere interacts with the magnetosphere. [less ▲]

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See detailSimultaneous Cassini VIMS and UVIS observations of Saturn's southern aurora: Comparing emissions from H, H2 and H3+ at a high spatial resolution
Melin, H.; Stallard, T.; Miller, S. et al

in Geophysical Research Letters (2011), 38

Here, for the first time, temporally coincident and spatially overlapping Cassini VIMS and UVIS observations of Saturn's southern aurora are presented. Ultraviolet auroral H and H[SUB]2[/SUB] emissions ... [more ▼]

Here, for the first time, temporally coincident and spatially overlapping Cassini VIMS and UVIS observations of Saturn's southern aurora are presented. Ultraviolet auroral H and H[SUB]2[/SUB] emissions from UVIS are compared to infrared H[SUB]3[/SUB][SUP]+[/SUP] emission from VIMS. The auroral emission is structured into three arcs - H, H[SUB]2[/SUB] and H[SUB]3[/SUB][SUP]+[/SUP] are morphologically identical in the bright main auroral oval (˜73°S), but there is an equatorward arc that is seen predominantly in H (˜70°S), and a poleward arc (˜74°S) that is seen mainly in H[SUB]2[/SUB] and H[SUB]3[/SUB][SUP]+[/SUP]. These observations indicate that, for the main auroral oval, UV emission is a good proxy for the infrared H[SUB]3[/SUB][SUP]+[/SUP] morphology (and vice versa), but for emission either poleward or equatorward this is no longer true. Hence, simultaneous UV/IR observations are crucial for completing the picture of how the atmosphere interacts with the magnetosphere. [less ▲]

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See detailEvolution of Saturn's Bright Polar Aurora
Stallard, T.; Grodent, Denis ULg; Badman, S. V. et al

Conference (2009)

Observations of Saturn's infrared aurorae have shown that in addition to the main auroral oval, which is believed to be associated with the solar wind, there are significant polar emissions. Ground-based ... [more ▼]

Observations of Saturn's infrared aurorae have shown that in addition to the main auroral oval, which is believed to be associated with the solar wind, there are significant polar emissions. Ground-based infrared observations of Saturn have been able to show that there is a general level of raised emission across the entire polar region, in a similar way to that seen at Jupiter. However, with direct observations of the aurora made from orbit around Saturn by the Cassini-VIMS instrument, this aurora was shown to be more than a relative generalised brightening in the infrared. Instead, a unique auroral feature was observed to occur, appearing as a large region of bright polar emission, positioned poleward of 82 degrees latitude. This Bright Polar Aurora emission is significantly different from the recently observed subrotating Q-branch auroral emission seen in both the ultraviolet and infrared, as it is separated from the main auroral oval by a region of low emission. This effectively produces a cap of bright aurora inside the main auroral oval, surrounded by a dark ring that separates the two aurorae. Here, we take a more detailed look at this cap of emission and examine the way the auroral feature develops with time. Bright Polar Aurora emission has been observed in two separate VIMS images. A more detailed analysis of the polar emission shows that each of these images in fact differs in structure; the first has auroral emission across the whole polar cap >82 degrees, but within the second the emission is concentrated on the dusk side. While the dramatic in-filling of the polar cap is not seen within any UV observations, the Hubble Space Telescope has observed transitory duskward auroral features within the polar cap, in a similar location to the duskward feature seen in the infrared. Using ground-based infrared observations, which allow a Bright Polar Aurora event to be broken into shorter timescale steps, it is possible analyse the progression of the infrared auroral emission with time, connecting the morphology seen within the two VIMS images with those in the ultraviolet. [less ▲]

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See detailOutreach goals of the Europa Jupiter System Mission
Blanc, M.; Coustenis; Nazé, Yaël ULg et al

Poster (2009)

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See detailAdaptive Aeroelastic Structures for Improved Aircraft Performance
Cooper, J. E.; Hodigere-Siddaramaiah, V.; Vio, G. A. et al

in Spencer Jr; Tomizuka, M.; Yun, C. B. (Eds.) et al World Forum on Smart Materials and Smart Structures Technology (2007, May)

There is a growing interest in the development of adaptive aeroelastic structures to allow aeroelastic deflections to be used in a beneficial manner. Part of the 3AS research programme was devoted towards ... [more ▼]

There is a growing interest in the development of adaptive aeroelastic structures to allow aeroelastic deflections to be used in a beneficial manner. Part of the 3AS research programme was devoted towards investigating the use of changes in the internal aerospace structure in order to control the static aeroelastic behaviour. Such an approach is desirable and arguably advantageous compared to other possible concepts. [less ▲]

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See detailDeep Impact: Observations from a Worldwide Earth-Based Campaign
Meech, K. J.; Ageorges, N.; A'Hearn, M. F. et al

in Science (2005), 310

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign ... [more ▼]

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics. [less ▲]

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See detailEstimated energy balance in the jovian upper atmosphere during an auroral heating event
Melin, H.; Miller, S.; Stallard, T. et al

Poster (2005)

We present an analysis of a series of observations of the auroral/polar regions of Jupiter, carried out between September 8 and 11, 1998, making use of the high-resolution spectrometer, CSHELL, on the ... [more ▼]

We present an analysis of a series of observations of the auroral/polar regions of Jupiter, carried out between September 8 and 11, 1998, making use of the high-resolution spectrometer, CSHELL, on the NASA InfraRed Telescope Facility (IRTF), Mauna Kea, Hawaii; these observations spanned an ``auroral heating event". This analysis combines the measured line intensities and ion velocities with a one-dimensional model of the jovian thermosphere/ionosphere (Grodent et al. 2001). We compute the model line intensities both assuming local thermodynamic equilibrium (LTE) and, relaxing this condition (non-LTE), through detailed balance calculations (Oka et al. 2004), in order to compare with the observations. Taking the model parameters derived, we calculate the changes in heating rate required to account for the modeled temperature profiles that are consistent with the measured line intensities. Comparison of the various heating and cooling terms enables us to investigate the balance of energy inputs into the auroral/polar atmosphere. Increases in Joule heating and ion drag are sufficient to explain the observed heating of the atmosphere; increased particle precipitation makes only a minor heating contribution. But local cooling effects - predominantly H[SUB]3[SUP]+[/SUP][/SUB] radiation-to-space - are shown to be too inefficient to allow the atmosphere to relax back to pre-event thermal conditions. Thus we conclude that this event provides observational, i.e. empirical, evidence that heat must be transported away from the auroral/polar regions by thermally or mechanically driven winds. [less ▲]

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See detailTemperature profiles in Jupiter's upper atmosphere
Melin, H.; Stallard, T.; Miller, S. et al

Poster (2003)

Recently, Stallard and coworkers observed an event in Jupiter's auroral polar regions that resulted in a temperature increase of around 125K during the period of approximately seven jovian rotations [1 ... [more ▼]

Recently, Stallard and coworkers observed an event in Jupiter's auroral polar regions that resulted in a temperature increase of around 125K during the period of approximately seven jovian rotations [1]. This "auroral event" involves a great deal of energy being deposited in the upper atmosphere - up to 250mW m[SUP]-2[/SUP]. Stallard et al. made these measurements using H_3^+ emission lines from the fundamental (v=1 rightarrow 0) and hotband (v=2 rightarrow 1) manifolds around 4μm. In this poster, we use the temperature profiles developed by Grodent and coworkers [2] in their one-dimensional model of the jovian aurorae to demonstrate that the lines used by Stallard et al. are formed at different altitudes in the atmosphere: the hotband is formed higher than the fundamental. We show a series of profiles, based on Grodent {et al.}'s original model that can be used to interpret future jovian spectra. [1] T. Stallard et al., 2002. Icarus 156, 498-514. [2] D. Grodent, J. Hunter Waite Jr. and J.-C. G&{acute;e}rard, 2001. J. Geophys. Res. 106, 12933-12952. [less ▲]

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See detailHubble Space Telescope far-ultraviolet imaging of Jupiter during the impacts of Comet Shoemaker-Levy 9
Clarke, J. T.; Prange, R.; Ballester, G. E. et al

in Highlights of Astronomy, Vol. 10 (1995)

Detailed reference viewed: 14 (4 ULg)
See detailAuroral Signature of the Interaction of Comet Shoemaker-Levy 9 with the Jovian Magnetosphere
Prangé; Emerich, C.; Rego, D. et al

in Bulletin of the American Astronomical Society (1994, June 01)

Not Available

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