Co-analysis of Galileo imaging observations of the gas and dust components of Io’s plumes suggests that the deposits produced by Prometheus-type plumes are made up of pyroclastic particles that are entrained with the gas flow. Peletype plumes, in contrast, deposit material that could be condensed from the gas phase. Introduction: Many outstanding questions remain to be answered about Io’s spect...

[1] The Carrington Event of 1859 is considered to be among the largest space weather events of the last 150 years. We show that only one out of 14 well-resolved ice core records from Greenland and Antarctica has a nitrate spike dated to 1859. No sharp spikes are observed in the Antarctic cores studied here. In Greenland numerous spikes are observed in the 40 years surrounding 1859, but where ot...

We present tomographic evidence for the existence of deep-mantle thermal convection plumes. P-wave velocity images show at least six well-resolved plumes that extend into the lowermost mantle: Ascension, Azores, Canary, Easter, Samoa, and Tahiti. Other less well-resolved plumes, including Hawaii, may also reach the lowermost mantle. We also see several plumes that are mostly confined to the upp...

Recently Brown eta/. (Science 250, 1991) showed that Triton's internal heat source could amount to 5-20% of the absorbed insolation on Triton, thus significantly affecting volatile transport and atmospheric pressure. Subsequently, Kirk and Brown (Proc. 22cd LPSC, 1991) used simple analytical models of the effect of internal heat on the distribution of volatiles on Triton's surface, confirming t...

Recently, the Cassini spacecraft observed an unexpected emission of plumes of water vapor, nitrogen, and icy particles from the southern polar region of Saturn’s icy moon Enceladus. While these findings support previous ideas of geological activity in this icy moon, there is no experimental evidence explaining how these plumes could be produced at the low (∼130–160 K) surface temperatures. Here...

An intriguing natural phenomenon occurs every polar spring, namely the bromine explosion, in which plumes of tropospheric monoxide (BrO) are formed. These observed BrO vertical column densities (VCDs), retrieved from satellite sensors. Tropospheric depletes ozone and facilitates deposition mercury. Bromine molecules mainly released young sea ice, meteorological parameters determine formation ev...

Using five spacecraft in geosynchronous orbit, plasmaspheric drainage plumes are located in the dayside magnetosphere and the measured pitch angle anisotropies of radiation belt electrons are compared duskward and dawnward of the plumes. Two hundred twenty-six plume crossings are analyzed. It is found that the radiation belt anisotropy is systematically greater dawnward of plumes (before the el...

Plumes are typically formed when a continuous source of buoyancy is supplied at a localized source. We studied laminar plumes where buoyancy is supplied by an autocatalytic chemical reaction: The iodate-arsenous acid (IAA) reaction. The nonlinear kinetics of the IAA reaction produces a sharp propagating front at which buoyancy is produced by exothermicity and compositional change. When the reac...