Detection of neutral oxygen and sulfur emissions near Io using IUE

Ballester, G. E.; Moos, H. W.; Feldman, P. D.; Strobel, D. F.; Summers, M. E.; Bertaux, J. L.; Skinner, Thomas E.; Festou, M. C.; Lieske, J. H.

doi:10.1086/184950

Cited by 53 publications

(33 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is composed primarily of SO 2 (Lellouch et al 1990(Lellouch et al , 1992 and SO (Lellouch et al 1996). The atomic byproducts of SO 2 , sulfur and oxygen, were first identified in the Io plasma torus (Brown 1981;Durrance, Feldman, & Weaver 1983) and more recently detected in Io's emission-line spectrum (Ballester et al 1987). Sodium (Burger & Schneider 1998;Geissler et al 1999;Bouchez, Brown, & Schneider 2000) and potassium (Brown 2001) are also present at much lower abundance than sulfur and oxygen.…”

Section: Introductionmentioning

confidence: 99%

“…Despite the recent advances in quantifying Io's atmosphere, including investigating the inhomogeneity and impact of volcanic activity (Feldman et al 2000;McGrath et al 2000;Spencer et al 2000), analyzing the air glow (Geissler et al 1999), and resolving the morphology (Roesler et al 1999;Retherford et al 2000), and the fact that several sets of sulfur and oxygen emission-line data have been acquired and analyzed (Ballester 1989;McGrath et al 2000;Oliversen et al 2001;Wolven et al 2001), the abundances are still not well constrained. Various observational measurements and theoretical models have placed loose bounds on the sulfur column density (N S ).…”

Section: Introductionmentioning

confidence: 99%

“…Various observational measurements and theoretical models have placed loose bounds on the sulfur column density (N S ). Previously, electron densities and temperatures were assumed in order to estimate N S , resulting in limits of 2:2 Â 10 12 cm À2 < N S < 7 Â 10 15 cm À2 (Ballester et al 1987;McGrath et al 2000). Recent observations make both optically thick and optically thin regimes available in a single exposure, allowing us to constrain N S without assuming a specific T e or n e .…”

Section: Introductionmentioning

confidence: 99%

“…We reanalyze a set of IUE observations of Io that span the spectral range 1150-1950 Å (Ballester 1989). Low-resolution $5 Å exposures of 13-14 hr in length were made over a 3 yr period with the short-wavelength (SWP) camera.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The Abundance of Atomic Sulfur in the Atmosphere of Io

Feaga

McGrath

Feldman

2002

ApJ

View full text Add to dashboard Cite

Observations with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope have been used to constrain the atomic sulfur column density in Io's atmosphere. The S i 1479 dipole allowed and forbidden transition multiplets have been resolved for the first time at Io, enabling the study of both optically thick and thin transitions from a single atomic species. The allowed transitions contribute 62% AE 8% and the forbidden transitions 38% AE 8%, on average, to the total signal of the S i 1479 multiplets. Using the optically thick and thin transitions of S i 1479 observed near the limbs of Io, we derive a tangential atmospheric sulfur column abundance of 3:6 Â 10 12 cm À2 < N S < 1:7 Â 10 13 cm À2 , which is independent of electron temperature and density. A low-density SO 2 atmosphere, N SO 2 $ 5 10 ð ÞÂ10 15 cm À2 , consistent with that inferred from other recent observations, is most consistent with these bounds.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The Abundance of Atomic Sulfur in the Atmosphere of Io

Feaga

McGrath

Feldman

2002

ApJ

View full text Add to dashboard Cite

show abstract

“…Important information on the atmosphere comes from observations in the ultraviolet (UV) wavelength range. Papers [Ballester et , 1987;Clarke et al, 1994;Durrance et al, 1995;Fox et al, 1997] report on observations of Io and its vicinity in the UV lines of oxygen OI and sulfur SI atoms. However, small spatial resolution precluded the study of the spatial structure of this radiation in these experiments.…”

Section: Introductionmentioning

confidence: 99%

On the Origin of Io’s Ultraviolet Aurora

Шапошников¹,

Zatsev²,

Rücker³

2011

Planetary Radio Emissions Vii

View full text Add to dashboard Cite

A model involving an additional contribution to Io's ultraviolet (UV) aurora is presented. A mechanism for heating of electrons of Io's ionospheric plasma up to sufficient energies for the excitation of Io's atmospheric oxygen and emitting of observed UV emission is proposed. The mechanism operates by the effect of the different magnetization of the electrons and ions in Io's ionosphere which in the course of Io's motion through the Jovian magnetic field causes the creation of a charge-separation electric field in the upstream part of the ionosphere. This field has a component parallel to the magnetic and shifts the electron distribution function relative to the ion distribution function by a value exceeding the thermal velocity of electrons. In this case, a Bunemann instability with a very large growth rate develops. This results in the excitation of turbulent pulsations at frequency close to the ion-sound frequency and the occurrence of anomalous resistance to the electric current. The latter causes heating of Io's ionospheric electrons up to a temperature of about 25 eV. Atmospheric oxygen molecules excited by collisions with the heated electrons of Io's ionosphere, whose density is about 6 × 10 4 cm −3 , can contribute to the observed UV brightness. The proposed model permits one to explain the correlation of UV brightness with Io's magnetic longitude and the discrepancy between the anti-Jovian equatorial UV spots and sub-Jovian spots as well.

show abstract

The Magnetospheres of the Outer Planets

McNutt

1991

Reviews of Geophysics

View full text Add to dashboard Cite

The past four years have witnessed the culmination of the initial reconnaissance of the giant outer planets and their magnetospheres. This includes more mature modeling of dynamics of and processes in the magnetospheres of Jupiter and Saturn, the first detailed reports on the fields and particles environment of Uranus, and the initial reports concerning the magnetosphere of Neptune, first sampled directly by Voyager 2 in August, 1989. Of the major bodies of the outer solar system, only the asteroids and the Pluto/Charon system remain unvisited, although some attention was focused on the latter during this quadrennium. We review work on and our understanding of the magnetospheres of all of the outer planets during the previous four years.

show abstract

Detection of neutral oxygen and sulfur emissions near Io using IUE

Cited by 53 publications

References 0 publications

The Abundance of Atomic Sulfur in the Atmosphere of Io

The Abundance of Atomic Sulfur in the Atmosphere of Io

On the Origin of Io’s Ultraviolet Aurora

The Magnetospheres of the Outer Planets

Contact Info

Product

Resources

About