aberration of starlight

aberration of starlight,

displacement of the apparent path of light from a star, resulting in a displacement of the apparent position of the star from its true position; discovered by the English astronomer James Bradley and explained by him in 1729. The phenomenon is caused by the orbital motion of the earth; in the same way, vertically falling raindrops appear to fall diagonally when viewed from a moving vehicle. The true path of light from a star to an observer is along the straight line from the star to the observer; but, because of the component of the observer's velocity in a direction perpendicular to the direction to the star, the light appears to be traveling along a path at an angle to the true direction to the star. Thus, in order to observe a star the central axis of a telescope must be tilted as much as 20.5" (seconds of arc) from the true direction to the star, the exact amount of the angle depending on the direction to the star relative to the direction of the earth's motion in its orbit. Because of the earth's orbital motion, the stars appear to move in elliptical paths on the celestial sphere. All these ellipses have the same semimajor axis, 20.5" of arc, a value known as the constant of aberration. The tangent of the constant of aberration is equal to the ratio of the earth's orbital speed to the speed of light.
References in periodicals archive ?
Aberration of Starlight. New York: Penguin Books, 1981; London: Boyars, 1981.
The second installment, False Pretenses, was finished in 1974, The Phantom Enthusiast in 1975; Charmed Particles (1979) was followed eight years later by The Lighted Field (1987), then Imaginary Light (1995), Time Being (2001), Free to Go (2003), and Aberration of Starlight (2008).
The structure of Time Being--indeed, the structure of all three of Noren's digital features (the other two are Free to Go and Aberration of Starlight)--is basically the same as the structures of the celluloid films: Once under way, the film presents an array of sequences during each of which a particular set of visual options is explored.
In the two Adventures that followed Time Being, Noren continued to investigate the visual options of digital; and while both Free to Co and Aberration of Starlight attest to his remarkable work ethic, both features also retreat from the engaging sensuality and intimacy that have infused so much of Noren's work.
On one level, the visual world Noren creates in Free to Go and Aberration of Starlight exploits the tendency toward graphic flatness that seems intrinsic to digital imagemaking; in these motion pictures, the movie screen does seem a veil, an illusion.
Bradley named this phenomenon the aberration of starlight. His own further observations of Eltanin revealed yet another cyclical (18.6-year) change in stellar positions: nutation, a slight conical motion of Earth's axis that is caused mainly by the Moon.
Sorrentino, on his way to becoming the Sorrentino of Mulligan Stew, published eight years later, and Aberration of Starlight and the rest, also seems determined to make one lose patience, though he never succeeds; his digressions don't annoy--in fact, just the opposite ("Don't tell me that this is a digression, this whole book is a digression: from the novel.
Aberration of Starlight (1980), accuses Guy Davenport in the New York Times Book Review, "openly steals from Joyce, O'Nolan, and Doctorow's Ragtime" (BR4).
What Aberration of Starlight makes clear is that Sorrentino's liftings from the treasure trove of period airs relate uniformly to the Depression.
Crystal Vision (1981), written before Aberration of Starlight, is understood on a level that is strictly hearsay.
Crystal Vision, like Aberration of Starlight, collaborates with the authority of the "Baltimore Catechism" on matters of dogma, and with that of the Brooklyn Tablet on matters of aesthetics: There's also a sculptor from Paris who dipped his balls in melted chocolate, Irish Billy says.
Aberration of Starlight. New York: Random House, 1980; Normal, IL: Dalkey Archive Press, 1993.