Showing papers on "Space weather published in 1972"

Solar cosmic ray hazard to interplanetary and earth-orbital space travel

Abstract: A statistical treatment of the radiation hazards to astronauts due to solar cosmic ray protons is reported to determine shielding requirements for solar proton events. More recent data are incorporated into the present analysis in order to improve the accuracy of the predicted mission fluence and dose. The effects of the finite data sample are discussed. Mission fluence and dose versus shield thickness data are presented for mission lengths up to 3 years during periods of maximum and minimum solar activity; these correspond to various levels of confidence that the predicted hazard will not be exceeded.

The significant solar proton events in 20th solar cycle for the period October 1964 to March 1970

Abstract: Solar proton data are presented from observations by the Explorer 21, 28, 34 and 41 satellites. The NASA Solar Particle Alert Network (SPAN) solar optical and radio frequency data for the period May 1967 to March 1970 are associated with the proton events observed by the Explorer 34 and 41 satellites; however, missing data are supplemented with data recorded at other international observatories. From a radiation hazard standpoint, NASA is concerned with solar proton events of the order of 10 to the 8th power proton/sq cm. Radiation dose data are presented for some of the large proton events that have occurred thus far in the 20th solar cycle and are compared with some of the large proton events of the 19th solar cycle. Finally, the results of a simple parametric correlation study are presented for both the 19th and 20th solar cycles.

Ionospheric and Solar Radio Studies for Disturbed Conditions.

Abstract: : The purpose of this contract is to study the atmosphere, the ionosphere and the magnetosphere of the Earth under disturbed conditions produced by enhanced solar activity. It also includes, therefore, the study of solar activity in the different regions of the spectrum with special emphasis in the radio domain. Data obtained with ground-based radio telescopes and satellites, together with related information concerning ionospheric parameters, magnetic field intensities, optical solar observations, etc., were used in the different projects under investigation, all of which have the common aim to gain a better understanding of the terrestrial disturbances caused by the active Sun. (Author)

Geomagnetic response to solar activity.

Abstract: The relationship between solar activity and geomagnetic variations is discussed in the light of spacecraft data obtained during the last decade The effects of centers of solar activity responsible for producing geomagnetic activity on earth are believed to be transmitted through the solar wind, and there is usually a delay of two or three days before the onset of magnetic activity Attempts to make a one-to-one correspondence between specific solar events and specific magnetic storms, however, are usually unsuccessful, because of the complex and indirect processes linking the two phenomena Normally, only statistical tendencies can be shown