Detection of H3+ on Jupiter

Drossart, P.; Maillard, Jean; Caldwell, John; Kim, S. J.; Watson, J. K. G.; Majewski, W. A.; Tennyson, Jonathan; Miller, Steve; Atreya, S. K.; Clarke, J. T.; Waite, J. H.; Wagener, R.

doi:10.1038/340539a0

Cited by 325 publications

(193 citation statements)

References 24 publications

Supporting

Mentioning

173

Contrasting

Unclassified

Order By: Relevance

“…The relative simplicity of the formation and destruction mechanisms of H þ 3 makes it possible, in principle, to derive fundamental physical characteristics of diffuse and dense clouds from its abundance. H þ 3 was first observed in laboratory spectra by Oka (1980), and nearly a decade later in the upper atmosphere of Jupiter (Drossart et al 1989). With the advent of more sensitive echelle spectrometers operating at infrared wavelengths on large telescopes, H þ 3 has now been detected in a variety of interstellar environments (Geballe & Oka 1996;McCall et al 1998McCall et al , 1999McCall et al , 2003Geballe et al 1999;Goto et al 2002;Kulesa & Black 2003).…”

Section: Introductionmentioning

confidence: 99%

Interstellar H₃⁺Line Absorption toward LkHα 101

Brittain

Simon

Kulesa

et al. 2004

ApJ

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

Interstellar H₃⁺Line Absorption toward LkHα 101

Brittain

Simon

Kulesa

et al. 2004

ApJ

View full text Add to dashboard Cite

show abstract

“…H + 3 emission was detected from the auroral regions of Jupiter by Drossart et al (1989). The ion was successfully used as a tool to measure atmospheric temperatures and ion densities of Jupiters atmosphere (Yelle 2004).…”

Section: Introductionmentioning

confidence: 99%

A CRIRES-search for H₃⁺emission from the hot Jupiter atmosphere of HD 209458 b

Lenz

Reiners

Seifahrt

et al. 2016

A&A

View full text Add to dashboard Cite

Close-in extrasolar giant planets are expected to cool their thermospheres by producing H + 3 emission in the near-infrared (NIR), but simulations predict H + 3 emission intensities that differ in the resulting intensity by several orders of magnitude. We want to test the observability of H + 3 emission with CRIRES at the Very Large Telescope (VLT), providing adequate spectral resolution for planetary atmospheric lines in NIR spectra. We search for signatures of planetary H + 3 emission in the L band, using spectra of HD 209458 obtained during and after secondary eclipse of its transiting planet HD 209458 b. We searched for H + 3 emission signatures in spectra containing the combined light of the star and, possibly, the planet. With the information on the ephemeris of the transiting planet, we derive the radial velocities at the time of observation and search for the emission at the expected line positions. We also apply a cross-correlation test to search for planetary signals and use a shift and add technique combining all observed spectra taken after secondary eclipse to calculate an upper emission limit. We do not find signatures of atmospheric H + 3 emission in the spectra containing the combined light of HD 209458 and its orbiting planet. We calculate the emission limit for the H + 3 line at 3953.0 nm [Q(1, 0)] to be 8.32 × 10 18 W and a limit of 5.34 × 10 18 W for the line at 3985.5 nm [Q(3, 0)]. Comparing our emission limits to the theoretical predictions suggests that we lack 1 to 3 magnitudes of sensitivity to measure H + 3 emission in our target object. We show that under more favorable weather conditions the data quality can be improved significantly, reaching 5 × 10 16 W for star-planet systems that are close to Earth. We estimate that pushing the detection limit down to 10 15 W will be possible with ground-based observations with future instrumentation, for example, the European Extremly Large Telescope.

show abstract

“…This has been performed for Jupiter, Saturn, and Uranus (e.g. Drossart et al 1989;Baron et al 1991;Trafton et al 1993;Rego 2000;Stallard et al 2008;Miller et al 2010), not only allowing determination of H + 3 densities and temperatures, but also providing valuable constraints for ionospheric models (e.g. Moore et al 2015).…”

Section: Introductionmentioning

confidence: 99%

EUV-driven ionospheres and electron transport on extrasolar giant planets orbiting active stars

Chadney

Galand

Koskinen

et al. 2016

A&A

Self Cite

View full text Add to dashboard Cite

The composition and structure of the upper atmospheres of extrasolar giant planets (EGPs) are affected by the high-energy spectrum of their host stars from soft X-rays to the extreme ultraviolet (EUV). This emission depends on the activity level of the star, which is primarily determined by its age. In this study, we focus upon EGPs orbiting K-and M-dwarf stars of different ages -Eridani, AD Leonis, AU Microscopii -and the Sun. X-ray and EUV (XUV) spectra for these stars are constructed using a coronal model. These spectra are used to drive both a thermospheric model and an ionospheric model, providing densities of neutral and ion species. Ionisation -as a result of stellar radiation deposition -is included through photo-ionisation and electron-impact processes. The former is calculated by solving the Lambert-Beer law, while the latter is calculated from a supra-thermal electron transport model. We find that EGP ionospheres at all orbital distances considered (0.1−1 AU) and around all stars selected are dominated by the long-lived H + ion. In addition, planets with upper atmospheres where H 2 is not substantially dissociated (at large orbital distances) have a layer in which H + 3 is the major ion at the base of the ionosphere. For fast-rotating planets, densities of short-lived H + 3 undergo significant diurnal variations, with the maximum value being driven by the stellar X-ray flux. In contrast, densities of longer-lived H + show very little day/night variability and the magnitude is driven by the level of stellar EUV flux. The H + 3 peak in EGPs with upper atmospheres where H 2 is dissociated (orbiting close to their star) under strong stellar illumination is pushed to altitudes below the homopause, where this ion is likely to be destroyed through reactions with heavy species (e.g. hydrocarbons, water). The inclusion of secondary ionisation processes produces significantly enhanced ion and electron densities at altitudes below the main EUV ionisation peak, as compared to models that do not include electron-impact ionisation. We estimate infrared emissions from H + 3 , and while, in an H/H 2 /He atmosphere, these are larger from planets orbiting close to more active stars, they still appear too low to be detected with current observatories.

show abstract

Detection of H3+ on Jupiter

Cited by 325 publications

References 24 publications

Interstellar H₃⁺Line Absorption toward LkHα 101

Interstellar H₃⁺Line Absorption toward LkHα 101

A CRIRES-search for H₃⁺emission from the hot Jupiter atmosphere of HD 209458 b

EUV-driven ionospheres and electron transport on extrasolar giant planets orbiting active stars

Contact Info

Product

Resources

About

Detection of H3+ on Jupiter

Cited by 325 publications

References 24 publications

Interstellar H3+Line Absorption toward LkHα 101

Interstellar H3+Line Absorption toward LkHα 101

A CRIRES-search for H3+emission from the hot Jupiter atmosphere of HD 209458 b

EUV-driven ionospheres and electron transport on extrasolar giant planets orbiting active stars

Contact Info

Product

Resources

About

Interstellar H₃⁺Line Absorption toward LkHα 101

Interstellar H₃⁺Line Absorption toward LkHα 101

A CRIRES-search for H₃⁺emission from the hot Jupiter atmosphere of HD 209458 b