Solar zenith angle minutes of arc, which is less than the apparent angular radius of the sun. The formula also neglects the effect of atmospheric refraction. Sunset and sunrise occur (approximately) when the zenith angle is 90°, where the hour angle "h" satisfies Precise times of sunset and sunrise occur when the upper limb of the Sun appears, as refracted by the atmosphere, to be on the horizon. A weighted daily average zenith angle, used in computing the local albedo of the Earth, is given by where "Q" is the instantaneous insolation. For example, the solar elevation angle is : An exact calculation
Less than Angels Less than Angels Less Than Angels is a novel by Barbara Pym, first published in 1955. The novel is largely concerned with the activities of a group of anthropologists, and is to some extent based on the author's own experiences working at the International African Institute in London. It is set in a period of social change which is subtly represented within the novel's plot and setting Catherine Oliphant is a young writer, who lives with anthropologist Tom Mallow. Tom begins a romance with a student, Deirdre Swann, and his relationship with Catherine fizzles out. At the same time, she