Buoyancy waves in Pluto's high atmosphere: Implications for stellar occultations

TL;DR

This study uses scintillation theory on high-resolution Pluto occultation data to identify buoyancy waves, revealing viscous-thermal dissipation effects and confirming gravity-wave behavior in Pluto's high atmosphere.

Contribution

It demonstrates the application of scintillation theory to planetary atmospheres, providing evidence for buoyancy waves and their dissipation mechanisms in Pluto's high atmosphere.

Findings

Identification of a high wavenumber cutoff in fluctuations

Evidence of viscous-thermal dissipation of buoyancy waves

Confirmation that density fluctuations follow gravity-wave dispersion

Abstract

We apply scintillation theory to stellar signal fluctuations in the high-resolution, high signal/noise, dual-wavelength data from the MMT observation of the 2007 March 18 occultation of P445.3 by Pluto. A well-defined high wavenumber cutoff in the fluctuations is consistent with viscous-thermal dissipation of buoyancy waves (internal gravity waves) in Pluto's high atmosphere, and provides strong evidence that the underlying density fluctuations are governed by the gravity-wave dispersion relation.