ISSN:0094-8276    

DOI:10.1029/GL010i002p00113

年代:1983

数据来源: WILEY

摘要:

During 1974 while analyzing photometer data obtained from the Atmosphere/Explorer‐C satellite, a significant brightness enhancement was discovered surrounding the velocity vector of the instrument. This enhancement appeared to be generated as a result of the interaction of the spacecraft with the atmosphere at a relative velocity of 8 km/sec. The enhancement was found to be inversely dependent on altitude and to have a broad spectral characteristic (the range covered was 3371 Å to 7320 Å) with the most intense effect occuring at the longer wavelengths. In this paper we review these earlier findings, and relate them to the observations of similar glows associated with the Space Shuttle. We also discuss glows that have been studied in laboratory experiments and others that have been reported on various rocket flights. We report a significant brightness enhancement associated with the vehicle w

ISSN:0094-8276    

DOI:10.1029/GL010i002p00114

年代:1983

数据来源: WILEY

摘要:

Photographic and television observations made during the third flight of the Space Shuttle in March 1982 reveal the presence of a diffuse optical emission surrounding surfaces of the vehicle exposed to the atmosphere in the ram direction. The line of sight intensity of this emission is comparable to that of airglow emissions seen at the limb of the earth and competes with the brightness of stars seen within the field of view of the photographic and TV cameras. The glow emission appears to be a manifestation of an atmosphere‐vehicle interaction. Light from vehicle thruster operations was also seen, as well as the optical emissions resulting from the operation of a 100 mA electron bea

ISSN:0094-8276    

DOI:10.1029/GL010i002p00118

年代:1983

数据来源: WILEY

摘要:

Following the discovery of intense vehicle glow of the space shuttle on the STS‐3 mission, a new experiment to probe this phenomenon was developed and flown on the shuttle STS‐4 mission. A conventional camera was equipped with an objective transmission grating and several photographic exposures were taken of the shuttle tail from the aft flight deck window. Vehicle glow surrounding shuttle surfaces exposed to the ram direction was observed on a long (400 second) exposure. From analysis of the resulting spectral data it appears that the shuttle glow has a diffuse spectral component in the region 6300 to 8000A. In addition, it has been possible to assess the spectral character of light emitted by the firing of a reaction control system thruster. Our data show that the light emitted from the thruster gases is confined to wavelengths shorter than 72

ISSN:0094-8276    

DOI:10.1029/GL010i002p00122

年代:1983

数据来源: WILEY

摘要:

Illumination was found recently in the ram direction of the Shuttle Orbiter arising from interaction with the ambient surrounding atmosphere. We have examined a similar optical glow by analyzing photometric data taken by the Visible Airglow Experiment on board the Atmosphere Explorer Satellites. Analysis at six different wavelengths from the ultraviolet to the near infrared suggests that the glow has a diffuse band or continuum spectrum which peaks in the red and probably in the infrared.

ISSN:0094-8276    

DOI:10.1029/GL010i002p00126

年代:1983

数据来源: WILEY

摘要:

It is argued that a plausible identification of the surface‐originating glow that has been observed on the AE‐E satellite and the space shuttle between 140 and 400 km is the OH Meinel band system. The emission appears to be generated by surface interaction with 5 eV O(³P) atoms at high altitude, and with 10 eV O2molecules below 160 km. The primary factors that favor this identification are the apparent spectral distribution and the deduced radiative lifetime, and if valid, implies that the total equivalent surface brightness of the vehicles is on the order of 10 MR, mainly in the near infr

ISSN:0094-8276    

DOI:10.1029/GL010i002p00130

年代:1983

数据来源: WILEY

摘要:

Observations and models show that sudden changes in the magnitude of the wind stress which occur within a time interval of one‐half inertial period are most effective in increasing surface current speeds and mixing the upper layers of the ocean. The purpose of the present study is to quantify the effects of concurrent time dependent wind direction. The Mellor‐Yamada level 2 1/2 turbulence closure model is used. A series of model runs was executed in order to determine the relative sensitivity of mixed layer depth and sea surface temperature to wind speed as compared with the rate of change of wind direction. The results indicate that the accuracy and time resolution of wind direction should be given special consideration in the design and interpretation of field experiments which will be used for testing prognostic mixed layer mod

ISSN:0094-8276    

DOI:10.1029/GL010i002p00133

年代:1983

数据来源: WILEY

摘要:

In the simple system CaSiO3‐FeSiO3‐MgSiO3, pyroxene M1 and M2 sites can be treated as distinct but interpenetrating solutions. In order to study the thermodynamics of the cation exchange between these sites, the simple mixture model is used as a first approximation of their nonideality. The intracrystalline cation distribution of iron and magnesium in synthetic pigeonite predicted in this way agrees well with experimental d

ISSN:0094-8276    

DOI:10.1029/GL010i002p00137

年代:1983

数据来源: WILEY

摘要:

New measurements of seismic velocity and attenuation have been made in the kiloHertz frequency range to temperatures of 120°C, confining and pore pressure to 200 bars in Berea sandstone. With increasing temperature, shear velocity and attenuation decrease at all pressures in a fully saturated rock. The data suggest that thermal relaxation is not a significant loss mechanism under these conditions. We propose that dissipation is controlled by a viscous fluid flow mechanism, in which a sharp frequency peak in attenuation is shifted from 2kHz at room temperature to 8 kHz at 120°C as the pore fluid viscosity is decreased with increasing temperature. However, the velocity decrease is too great to be accounted for by a change of relaxation times. A non‐dispersive temperature softening in shear may control the velocit

ISSN:0094-8276    

DOI:10.1029/GL010i002p00140

年代:1983

数据来源: WILEY

摘要:

Springtime concentrations of hydrocarbons and chlorocarbons in the arctic atmosphere (70°N, Barrow) are reported. Concentrations of the following gases were determined: acetylene (C2H2), ethene (C2H4), ethane (C2H6), propane (C3H8), benzene (C6H6), toluene (C7H8), perchloroethylene (C2Cl4), and trichloroethylene (C2HCl3). Vertical distributions of these gases were also determined on flights during May 1982. The results show that C2Cl4, C2H2, and C2H6may be gaseous tracers of arctic haze. Their vertical profiles suggest that polluted air may be transported to the arctic 1‐2 km above ground, and perhaps also in layers higher than this lev

ISSN:0094-8276    

DOI:10.1029/GL010i002p00144

年代:1983

数据来源: WILEY