Comments on the excitation of the geocoronal H alpha nightglow

Excitation of geocoronal hydrogen alpha nightglo

The problem of using Mariner IV IONOSPHERIC densities to deduce a model of the Martian atmospheric structure

Martian atmosphere model deduced from Mariner IV IONOSPHERE electron density measurement

The problem of sodium distribution

Diurnal variations of free sodium atoms in upper atmospher

Detection of High Altitude Explosions by Observation of Air Fluorescence

Detection of high altitude explosions based on observation of fluorescence radiation of excited nitrogen molecule or nitrogen ion from ground and from satellite

Some considerations concerning radiation transport in the oi 1304 triplet in the upper atmosphere

Radiation transfer in optically thick medium - relation to 1304 OI triplet in upper atmospher

The polar ion flow - Wind or breeze /ques/

Hydrodynamic and evaporative theories of light ion flow in polar region

Elegance of disordered granular packings: a validation of Edwards' hypothesis

We have found a way to analyze Edwards' density of states for static granular packings in the special case of round, rigid, frictionless grains assuming constant coordination number. It obtains the most entropic density of single grain states, which predicts several observables including the distribution of contact forces. We compare these results against empirical data obtained in dynamic simulations of granular packings. The agreement is quite good, helping validate the use of statistical mechanics methods in granular physics. The differences between theory and empirics are mainly related to the coordination number, and when the empirical data are sorted by that number we obtain several insights that suggest an underlying elegance in the density of states.Comment: 4 pages, 5 figures, Changes in the reference

Atomic oxygen between 80 and 120 km: Evidence for a rapid spatial variation in vertical transport near the ionosphere

Analysis of OGO-6 OI green line photometer results was carried out for 8 cases when the alignment of the spacecraft was such that local emission rates could be determined below the altitude of maximum emission and down to about 80 km. Results show a variation on a scale of 6 deg to 8 deg in latitude between regions where the emission rate increases rapidly between 90 and 95 km and regions where it increases slowly from 80 km to 95 km. Latitude-altitude maps of iso-emissivity contours and iso-density contours for oxygen concentration are presented. The latter are computed under 3 assumptions concerning excitation mechanisms. Comparisons of the spatial variations of oxygen density with the results of a time dependent theory suggest the regions of strong downward transport alternate on a scale of about 1000 km with regions of weak transport near 90 km. In the first case conversion of O to O3 at night appears to be overwhelmed by downward transport of O

Analysis of OGO-6 observations of the 0 I 5577A tropical nightglow

Atomic oxygen green line data from the horizon scanning photometer on OGO-6 was examined. Unfolding the satellite data from the tropical F-region yields altitude and latitude variations of the O(1S) emissions. The spatial variations of the tropical F-region electron density are then calculated by assuming dissociative recombination and using a model atmosphere. Where comparisons to ground-based data are possible the results are good. Thus, the satellite observations constitute a form of topside sounding of the ionosphere below the F-peak and provide synoptic data about this portion of the ionsphere otherwise impractical to obtain

Rocket investigation of the auroral green line

Dissociative excitation and recombination reactions of atomic oxygen by auroral electrons, related to auroral green lin