Sounding Rockets Their Role in Space Research (1969) / Chapter Skim
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Appendix: Rocket Results 1965-1968
Appendix: Rocket Results 1965-1968
Pages 15-51
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From page 15... ...
Such studies have provided a check on radiation transfer theory applied to such stars and have identified high-velocity mass loss in hot supergiant stars. They have also provided the most accurate measure of interstellar density and have set limits to the role played by molecular hydrogen as a reservoir of galactic matter.
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From page 16... ...
The Atomic Energy Commission's rocket development program is largely carried out by the Sandia Corporation. For the past three years the LRL group has been building scientific instruments to fly on the Sandia-launched rockets, which are multi-stage, solid fuel, sounding rockets.
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From page 17... ...
Studies of the source Sco XR-l yielded a position accurate to about l arc min and an upper limit to the diameter of 20 arc sec. This information, in turn, has led to the optical identification of the source as an intense ultraviolet object of about l8th magnitude.
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From page 18... ...
MIT has been carrying out a medium precision x-ray astronomy mapping program using proportional counters and attitude-controlled Aerobees, with the following recent results: confirmation of x radiation from M87; celestial positions of x-ray sources in Sagittarius with a precision of about l5 min; spectral measurements of Sco XR-l to l8 A; upper limit to x radiation from a two-week old supernova. The MIT group is exploiting the modulation collimator techniques to measure source sizes and locations in its forthcoming flights.
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From page 19... ...
A new result was the observed lack of molecular hydrogen band absorption in the Zeta Puppis and Gamma Velorem spectra near ll00 A This result established an upper limit on the interstellar molecular hydrogen concentration at ten percent of the atomic hydrogen concentration deduced from the interstellar Lyman-alpha absorption line.
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was flown from White Sands. The instrument scanned the Orion region and spectra were obtained for about 20 stars, most of which yielded usable data covering spectral types from 08 through A3.
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Absorption by NH3 appears to be present in the Jupiter spectra, but in a concentration orders of magnitude less than suggested by ground-based observations. University of Florida - Kitt Peak National Observatory.
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For the quiet Sun, local brightness variations were found to be limited to + 30 percent with steep gradients between regions of different brightness, and structures as small as the 2-arc sec resolution limit were observed. NASA Goddard Space Flight Center.
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Energetic particle precipitation from the magnetosphere, visible auroral displays, enhanced ionization, Electric fields, and intense ionospheric currents (electrojets) , form the roster of auroral parameters to be observed by sounding rockets.
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From page 24... ...
Moreover, in l967 when the solar activity had started to rise, the current density was found to be greater and the electrojet apparently wider than in l965. New Techniques Although ionospheric current measurements have been sparse since l965, three new techniques have been introduced to allow measurement of the electric fields that drive the currents.
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From page 25... ...
Auroral Studies The aurora is a complex phenomenon involving precipitation of particles from the magnetosphere, enhanced ionization, auroral light, electrojet currents, and electric fields. Rocket payloads equipped to measure several of these parameters are more valuable than payloads that measure only one variable.
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From page 26... ...
The contributions of sounding rockets to cosmic ray studies are no less significant. Studies of low energy cosmic rays, and in particular the occurrence and composition of solar cosmic rays, have contributed valuable data not only for Earth-oriented applications such as ionospheric disturbances but also for studies of astrophysical interest.
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From page 27... ...
The fourth was made at night during a visible aurora. The elextron spectra apparently reveal the presence of monoenergetic primary electrons in the visible auroral display, a finding which implies the existence of electric fields along magnetic field lines above the auroral zone.
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From page 28... ...
PCA or Solar Cosmic Ray Events NASA Goddard Space Flight Center. Rockets have provided vital data on energetic solar cosmic rays and their precipitation into the atmosphere.
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It is also noteworthy that rocket flights from l963 through l965 measured low energy galactic cosmic rays. These particles cannot be observed from the ground or with balloons and are of vital importance to the resolution of long-standing problems about cosmic rays.
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(3) Dynamical properties of the ionosphere are represented by processes such as: the ambipolar diffusion of the ionization; its collisional interaction with the moving neutral atmosphere; the convection of ionization by electric fields, either in the dynamo region or in the outer part of the magnetosphere; and the effects of these motions on the ionization distribution itself.
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From page 31... ...
It is expected that these data will allow a significant study of the relation of winds and electron density during the 7-hour period. NASA Goddard Space Flight Center.
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A winter daytime measurement at White Sands under somewhat disturbed conditions showed a positive ion density minimum at a lower altitude than that obtained in l964 under quiet solar conditions. The electron density was greater than l00 cm" 3 in the 50-to-60 km range, but the negative ion/electron ratio increased above 60 km indicating the predominance of a readily detached negative ion below 60 km and of a much more stable negative ion above that height.
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From page 33... ...
Electron densities below 65 km were greater in l966 than in l967. Four rocket electron density profiles from southern Brazil during the total solar eclipse in November l966 reveal several features which have implications regarding D-region photochemical processes.
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Electron and Ion Temperature GCA Corporation. Langmuir probe measurements of electron temperature have been made on a large number of rockets which also made electron density measurements in the E region (see previous University of Illinois Section)
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From page 35... ...
It is found that significant deviations from diffusive equilibrium can exist. A Javelin rocket launched by the Planetary Ionospheric Branch in September l965 from Wallops Island simultaneously measured ion composition and temperature, and electron density and temperatures in the F region and topside ionosphere.
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From page 36... ...
An Aerobee rocket, launched from White Sands at ionospheric sunset, carried two Bennett ion mass spectrometers and a planar ion trap; it traversed a dense blanketing type of sporadic-E layer on both ascent and descent. Metallic ions, primarily Mg , were the main ion species detected within the layer.
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From page 37... ...
Although this group is primarily interested in auroral particles and emissions, two VU receivers have been flown to study VLF propagation characteristics and antenna impedance. Secondary objectives were to deduce electron density and ion composition.
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From page 38... ...
The electron density profile obtained from the antenna data agreed with the ground-based ionosonde profile taken during the flight. Two other experiments to determine local plasma frequency were also flown.
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From page 39... ...
The l356 A atomic oxygen line has been shown to be produced by photoelectron excitation as are the molecular nitrogen Lyman-Birge
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From page 40... ...
The gamma and delta bands of nitric oxide dominate the spectrum between l750 and 2750 A Horizon brightening and zenith-nadir intensity ratios of the atomic hydrogen l2l6 A and atomic oxygen l304 A lines have been measured.
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From page 41... ...
Seven rockets have been launched into active nighttime auroras at Fort Churchill since l965. The energy spectra of electrons in the range from 2 to 50 keV, electron temperatures and densities, electric field strengths, and emission rates of 0I 5577 A and N£ 39l4 A have been measured simultaneously.
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From page 42... ...
It is necessary to measure not only the major constituents, molecular nitrogen, molecular oxygen, and atomic oxygen, but such minor constituents as electronically excited molecular oxygen, ozone, and nitric oxide. The measurements of the vertical profile of these species as a function of geographic location and time provides the basic data for understanding the motions and energy balance of the atmosphere, and the formation of the ionosphere in this region.
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From page 43... ...
Quadrupole mass spectrometers have been flown with exposed ion sources, and have found that atomic oxygen is higher in the daytime than at night and is less at high latitudes. Measurements have been taken at Fort Churchill, Wallops Island, and near the Equator.
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From page 44... ...
Seven Aerobee flights at the White Sands Missile Range have been flown since early l965. In each case the rocket carried three magnetic deflection mass spectrometers to observe neutral composition.
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From page 45... ...
This data will be used to determine the mechanisms creating and destroying nitric oxide between 60 and 85 km. An Aerobee launched from White Sands Missile Range in October l967 measured the solar Lyman-alpha profile.
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From page 46... ...
These phenomena are dynamic, their energy deriving for the most part from solar radiation absorbed by the ground, water vapor, ozone, and molecular oxygen. On the long time scale the general circulation of the atmosphere can be considered to consist primarily of a zonal wind whose coriolis acceleration is in balance with the north-south pressure gradient resulting primarily from similar gradients in solar heating, but significantly influenced by secondary meridional circulations and mean fluxes due to smaller scale motions (sometimes called eddies)
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From page 47... ...
White Sands Missile Range. Scientists associated with the Range have developed, for use in the Meteorological Rocket Network, a rocket-borne parachute wind-measuring system with a claimed accuracy of ± 3 m sec"*
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From page 48... ...
They found that the usual spiral profiles often appear to collapse in a period of six hours -- suggesting the nonlinear breakdown of tidal fields. White Sands Missile Range.
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From page 49... ...
University of Washington. MRN and other rocket data have been used to detect and describe the semi-annual zonal wind oscillation that appears to dominate the circulation in the equatorial mesosphere.
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