Eclipse period

Viruses, like all pathogens, show host specificity, usually infecting only one or a restricted range of host species. The initial basis of specificity is the ability of the virus particle to attach to the host cell. If the amount of infectious virus is measured over a period of time in the host, it is seen to fall, after an initial lag period, remain low for a period of time, and then rise to even higher levels. The period during which the amount of virus is low is referred to as the eclipse period. The virus infection cycle can be divided into several events. 

Expression of the Viral Genetic Material. This occurs during the eclipse period, when the amount of infectious virus appears low. Several events occur during the eclipse phase ... 

Eclipse period Period during which viruses have absorbed to and penetrated host cells but cannot yet be detected in cells. 

Battery Requirements. A 96-min orbit is typically used to characterize LEO satellite applications. The time it takes a satellite to orbit the earth at 555 km is 96 min. The satellite orbits the earth 15 times in one day. The orbital duration remains fixed, but the sunlight and eclipse periods vary with each orbit. For example, a LEO satellite orbiting 555 km above the earth, at an inclination of 28.3°, has an orbital period that is constant at 96 min but during a given month, such as December 1991, the ecUpse durations vary from a maximum of 35.58 min on December 1 to a minimum of 26.97 min on December 30. 

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