second of arc


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Related to second of arc: Arcseconds

second of arc

n.
See second1.
References in periodicals archive ?
Recently, at the Royal Greenwich Observatory in England, an analysis of occultations observed in 1958 and 1959 revealed a cyclic discrepancy [in the Moon's orbital latitude, up to] a large fraction of a second of arc, even after corrections for lunar limb irregularities have been applied.
75 second of arc, about a thousandth of the width of a full moon.
The particular problem the Stanford team looked at, labeled Gravity Probe B, was Einstein's assertion that an object such as the Earth would cause a very slight alteration to the space-time around it - in Earth's case, actually causing space itself to rotate, by a mere 37 one-thousandths of one second of arc.