An interactive computer program for sizing spacecraft momentum storage devices

An interactive computer program was developed which computes the sizing requirements for nongimbled reaction wheels, control moment gyros (CMG), and dual momentum control devices (DMCD) used in Earth-orbiting spacecraft. The program accepts as inputs the spacecraft's environmental disturbance torques, rotational inertias, maneuver rates, and orbital data. From these inputs, wheel weights are calculated for a range of radii and rotational speeds. The shape of the momentum wheel may be chosen to be either a hoop, solid cylinder, or annular cylinder. The program provides graphic output illustrating the trade-off potential between the weight, radius, and wheel speed. A number of the intermediate calculations such as the X-, Y-, and Z-axis total momentum, the momentum absorption requirements for reaction wheels, CMG's, DMCD's, and basic orbit analysis information are also provided as program output

Interplanetary sector structure, 1962 - 1966

Properties of interplanetary magnetic field observed by IMP-

A possible correlation between maxima of the far ultraviolet solar irradiance and central meridian passages of solar magnetic sector boundaries

Satellite observations of the sun over almost 5 yrs show that principally two UV active longitudes have persisted over a significant portion of this observational period. A comparison between the position of solar magnetic sector boundaries and UV enhancements of the sun seems to show, at least during the year 1969, that the UV maxima tend to occur near the times when a solar sector boundary is near central meridian. An estimate of the magnitude of the variable UV solar energy input into the atmosphere resulting from the rotation of active solar longitudes is that for wavelengths less than 175 nm and down to H Lyman-alpha it exceeds the annual variation, whereas at longer wavelengths it is less

Solar source of the interplanetary sector structure

Comparison of satellite interplanetary magnetic field observations with photospheric magnetic field and plage structur

Black Rot

NYS IPM Type: Fruits IPM Fact SheetBlack rot is an important fungal disease of grapes that originated in eastern North America, but which now occurs in portions of Europe, South America, and Asia as well. It can cause complete crop loss in warm, humid climates, but is virtually unknown in regions with arid summers. There is a wide variation in susceptibility to this disease among native American and hybrid cultivars, whereas all common cultivars of Vitis vinifera appear to be highly susceptible

Science leadership for tomorrow: The role of schools of public affairs and universities in meeting needs of public science agencies

Recommendations and requirements for the preparation of personnel with some scientific or technological background to enter fields of public policy and administration are reported. University efforts to provide science administration graduate programs are outlined and increased cooperation between government and university resources is outlined

A Topological Definition of Resonance Energy

A topological definition of resonance energy is proposed that is linearly correlated with the Hess and Schaad definition of resonance energy. It is shown that the derived topological parameters can be correlated with the results o.f a SCF :n:-electron model

Movie of the interplanetary magnetic field

Description of movie representing IMP-1 MAGNETOMETER observations of interplanetary magnetic fiel

A Topological Definition of Resonance Energy

A topological definition of resonance energy is proposed that is linearly correlated with the Hess and Schaad definition of resonance energy. It is shown that the derived topological parameters can be correlated with the results o.f a SCF :n:-electron model

Interplanetary magnetic field IMP-1, motion picture of the transverse components

Motion picture report of IMP-1 magnetometer observations of interplanetary magnetic fiel