(In the transit of a planet across the sun) either of the points at the start and end of the transit (second and third contacts) when the planet is just within the edge of the sun's disc.
Origin
Mid 18th century; earliest use found in Philosophical Transactions of the Royal Society of London.
Definition of internal contact in US English:
internal contact
noun
Astronomy
(In the transit of a planet across the sun) either of the points at the start and end of the transit (second and third contacts) when the planet is just within the edge of the sun's disc.
Origin
Mid 18th century; earliest use found in Philosophical Transactions of the Royal Society of London.