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We test a theory presented previously to account for the turbulent transport of magnetic uctuation energy in the solar wind and the related dissipation and heating of the ambient ion population. This theory accounts for the injection of magnetic energy through the damping of large-scale ow gradients such as wind shear and compression, and incorporates the(More)
Collisions between the winds of solar-like stars and the local ISM result in a population of hot hydrogen gas surrounding these stars. Absorption from this hot H I can be detected in high resolution Lyα spectra of these stars from the Hubble Space Telescope. The amount of absorption can be used as a diagnostic for the stellar mass loss rate. We present new(More)
Redshifted Lα absorption toward α Cen has been interpreted by Linsky & Wood (1996) and Frisch et al. (1996) as evidence for decelerated interstellar hydrogen piled up on the upstream side of the heliosphere. We utilize newly developed two-dimensional multi-fluid models of the solar wind interaction with the ISM to corroborate this interpretation by(More)
The gas-to-dust mass ratios found for interstellar dust within the Solar System, versus values determined astronomically for the cloud around the Solar System, suggest that large and small interstellar grains have separate histories, and that large interstellar grains preferentially detected by spacecraft are not formed exclusively by mass exchange with(More)
As the Sun moves through the local interstellar medium, its supersonic, ionized solar wind carves out a cavity called the heliosphere. Recent observations from the Interstellar Boundary Explorer (IBEX) spacecraft show that the relative motion of the Sun with respect to the interstellar medium is slower and in a somewhat different direction than previously(More)
Mechanisms for the deposition of heat in the lower coronal plasma are discussed, emphasizing recent attempts to reconcile the Ñuid and kinetic perspectives. Structures at magnetohydrodynamic (MHD) scales may drive a nonlinear cascade, preferentially exciting high perpendicular wavenumber Ñuctuations. Relevant dissipative kinetic processes must be identiÐed(More)
We use high-resolution UV spectra taken by the Space Telescope Imaging Spectrograph instrument on board the Hubble Space Telescope to study the 5.5 pc line of sight to the K0 V star 36 Oph A. The one interstellar component detected for this line of sight has a velocity inconsistent with the local interstellar cloud (LIC) flow vector, but consistent with the(More)
We search the Hubble Space Telescope (HST) archive for previously unanalyzed observations of stellar H I Lyα emission lines, our primary purpose being to look for new detections of Lyα absorption from the outer heliosphere, and to also search for analogous absorption from the astrospheres surrounding the observed stars. The astrospheric absorption is of(More)
At present, the heliosphere is embedded in a warm low density interstellar cloud that belongs to a cloud system flowing through the local standard of rest with a velocity near ∼18 km s. The velocity structure of the nearest interstellar material (ISM), combined with theoretical models of the local interstellar cloud (LIC), suggest that the Sun passes(More)
Nearly incompressible viscous hydrodynamic fluids are investigated using nonlinear fluid simulations. Nearly incompressible fluids possess acoustic modes through high frequency fluctuations associated with the subsonic fluid Mach number. These modes, in combination with the fluid modes, drive linearly unstable modes and nonlinearly excite flows. The(More)