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Romick, G. J.

Publications and source records attributed to Romick, G. J..

16 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Stratospheric nitrogen dioxide in the vicinity of Soufriere, St. Vincent

In April 1979, measurements of nitrogen dioxide in the upper atmosphere were made near Soufriere Volcano by twilight optical-absorption techniques. The derived value of 5 x 10 to the 15th molecules per square centimeter column implies an enhancement of 25 percent over earlier abundances measured in the same latitudinal regions. This enhancement may represent the normal stratospheric variability of nitrogen dioxide in the equatorial region, but in any case may be considered an upper limit to the volcano's effect on the total nitrogen dioxide abundance.

Romick, G. J.↗
NASA NTRS1982

A critical velocity interaction between fast barium and strontium atoms and the terrestial ionospheric plasma

A disk of barium and strontium vapor traveling radially outward, perpendicular to the geomagnetic field lines, may be created by the detonation of a high-explosive, radially shaped charge with a liner composed of the two metals in the upper atmosphere. Because of solar radiation resonance, both the barium and the strontium may be optically tracked. Observations indicate the early formation of the metal ions thus evolved into a disk-shaped, stellate structure with a dark hole at the center of a radial structure. The results of these experiments indicate that the process could occur on a cosmic scale, and that unconfirmed aspects of the theory relating to this process could be determined through variation of the parameters in future radial rocket experiments.

Deehr, C. S.↗
NASA NTRS1980

A high-altitude barium radial injection experiment

A rocket launched from Poker Flat, Alaska, carried a new type of high-explosive barium shaped charge to 571 km, where detonation injected a thin disk of barium vapor with high velocity nearly perpendicular to the magnetic field. The TV images of the injection are spectacular, revealing three major regimes of expanding plasma which showed early instabilities in the neutral gas. The most unusual effect of the injection is a peculiar rayed barium-ion structure lying in the injection plane and centered on a 5 km 'black hole' surrounding the injection point. Preliminary electrostatic computer simulations show a similar rayed development.

Wescott, E. M.↗
NASA NTRS1979

Magnetosphere-ionosphere interactions

The present understanding of magnetosphere ionosphere interactions is described, and present and future predictive capabilities are assessed. Ionospheric features directly coupled to the magnetosphere to a significant degree are considered, with emphasis given to those phenomena of major interest to forecasters and users.

Vondrak, R. R.↗
NASA NTRS1978

Variability in the determination of total atmospheric ozone using remote sensing spectroscopic techniques

A spectroscopic method for remote sensing of total ozone has been applied to airborne observations of solar near-UV radiation in the 3100 to 3600 A wavelength region. The method involves detailed spectral matching of the solar observations with synthetic profiles containing various amounts of ozone absorption. For the 3100-3200 A region, measurements above the tropopause agree well with Broadfoot's (1972) extra-terrestrial solar irradiance values. Discrepancies between the observed spectra and the synthetic profiles at other wavelength regions may be due to distorted ozone absorption coefficients or the presence of other UV-absorbing species in the stratosphere.

Sivjee, G. G.↗
NASA NTRS1977

Auroral O I /989 A/ and O I /1027 A/ emissions

Rocket observations of the extreme ultraviolet spectrum of the aurora from 550 to 1250 A are presented, and the results for the O I (989 A) and O I (1027 A) multiplets are examined in detail. The intensity of these emissions and the observed anisotropic radiation field are inconsistent with the relative intensity of the branching radiations. Several possible solutions to the problem are discussed, and evidence is presented that suggests the need to lower the branching ratios by several orders of magnitude.

Christensen, A. B.↗
NASA NTRS1976

Airborne ultraviolet studies of Venus

Airborne ultraviolet studies of Venus were carried out during the NASA-ESO Space Shuttle simulation program. The primary wavelength region monitored was between 2950 and 3350 A in the third order. Measurements of solar radiation reflected from Venus were obtained on five flights at elevation angles of 15-30 deg. Direct solar and lunar spectra were obtained for the same elevation angles during two of the flights. Typical solar and Venutian spectra are presented.

Sivjee, G. G.↗
NASA NTRS1974

Optical aurora and its relationship to measurements from satellites, VHF radar and incoherent scatter radars

Examples are given of coordinated programs in Alaska which involve satellites, radars, ground optical instrumentation, and other types of observing satellites for the study of atmospheric and magnetospheric geophysics. Programs include coincidence data acquisition, scheduled data acquisition, and planned experiments. The use of optical triangulation techniques to determine the position of the aurora in order to place the other measurements in the perspective of the overall auroral morphology is detailed.

Romick, G. J.↗
NASA NTRS1973

Coordinated observations of chemical releases from the ground and from aircraft at high latitudes

The ground observations of the Na-Li trail released from a Nike-Apache rocket obtained by the Geophysical Institute are discussed. By using the nominal trajectory for a 60 pound payload and the particular rocket, a best fit trajectory was determined based on the Ester Dome photographic data, launch time and earth-sun geometrical shadow height. From these calculations, the height of obvious features along the trail were determined and their velocity estimated. A clockwise rotation of the velocity vector with increasing height was observed. Velocities deduced at various altitudes were then compared to meter radar data also obtained during this period. The comparisons of these two neutral wind measurements techniques are satisfactory.

Romick, G. J.↗
NASA NTRS1973

The hydroxyl emissions in relation to the dynamical processes of the atmosphere

Ground and airborne hydroxyl emission observations were made in the northern polar regions. The ground observations were made at Ester Dome, Alaska, and the airborne observations were made during the 1969 NASA Airborne Expedition. The analysis of some of the data that were acquired has lead to the following conclusions: (1) Airglow OH measurements show no appreciable change with latitude or longitude. (2) Diurnal changes at northern latitudes are similar to those observed in midlatitude regions. (3) Two types of OH enhancements were observed photometrically in the 9370 A region - one associated with visible aurora, and the other uncorrelated with visible aurora. High resolution spectra under both inactive and active conditions indicate that the OH enhancements seen photometrically in active aurorae are probably due to contamination of the filter pass bands by the unexpected enhancement of the NI multiplet lines at 9387 A and 9393 A. All previously reported aurorally associated enhancements are consequently suspect.

Romick, G. J.↗
NASA NTRS1972

Analysis of photometric data obtained on the 1969 NASA airborne auroral expedition

The analysis of the 1969 airborne expedition data is centered around two main topics: dayside auroral characteristics and hydroxial airglow variations. Some of the conclusions drawn from the analysis include the following: (1) The midday sector of the auroral oval is bound on the equatorward side by a region of greater than or = to 3 keV electrons. (2) The dayside oval is associated with the cusp region in the magnetosphere which has particle energies usually less than or = to 1 keV and lambda 6300 (OI)/lambda 4278 N2(+) ratios 10. (3) Discrete earth-sun aligned auroras appear in the polar cap just poleward of the oval superimposed on a 1 keV particle energy background. (4) The discrete earth-sun aligned auroras seen in the open field line region on the dayside have a similar appearance to some rayed auroras seen on the nightside both in terms of charactertistic particle energy spectra as well as visual appearance. (5) Airglow OH measurements show no appreciable change with latitude or longitude but do show diurnal changes. Two types of enhancements are observed: one associated with visible aurora, and the other uncorrelated with visible aurora.

Romick, G. J.↗
NASA NTRS1971

Midday auroral observations in the oval, cusp region, and polar cap.

Evaluation of combined photographic and photometric measurements made on the 1969 NASA airborne expedition, yielding a description of the midday oval, cusp region, and polar cap auroral precipitation at low magnetic activity (Kp = 0, 1+). The observations delineate three regions through the description of the type of aurora observed and the photometrically inferred change in energy of the particles: (1) the region in and equatorward of the oval where greater than 3-keV electrons are associated with 6300 A/4278 A ratios less than or equal to 1 and with a diffuse glow or structured arcs; (2) the cusp region where electrons of several hundred electron volts and spikes of more energetic electrons are associated with 6300 A/4278 A ratios between 10 and 35 in broken, fragmented, rayed features and patches; (3) the polar cap where discrete earth-sun-aligned arcs have height luminosity profiles in 5577 A, 6300 A (forbidden O I), and 4278 A (N2(+)) that suggest incoming electrons with an energy spectrum of 2-keV characteristic energy above a low-energy (few hundred electron volts) background.

Romick, G. J.↗