heliacal rising

British  

/ hɪˈlaɪəkəl /

noun

1. the rising of a celestial object at approximately the same time as the rising of the sun

2. the date at which such a celestial object first becomes visible in the dawn sky

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Etymology

Origin of heliacal rising

C17: from Late Latin hēliacus relating to the sun, from Greek hēliakos, from hēlios the sun

Example Sentences

The Sothiac period, or that cycle in which the heliacal rising of Sirius passed the whole civil year, and took place again on the same day, was of 1461 years, not 14,601.

From Personal Recollections, from Early Life to Old Age, of Mary Somerville by Somerville, Mary

We recognize to-day this "heliacal rising" of the stars.

From The Astronomy of the Bible An Elementary Commentary on the Astronomical References of Holy Scripture by Maunder, E. Walter (Edward Walter)

In Egypt, another reason was, that then the Nile began to overflow, at the heliacal rising of Sirius.

From Morals and Dogma of the Ancient and Accepted Scottish Rite of Freemasonry by Pike, Albert

The more precise fixing of new year's day was accomplished through observation of the time of the so-called heliacal rising of the dog-star, Sirius, which bore the Egyptian name Sothis.

From A History of Science — Volume 1 by Williams, Edward Huntington

Dog-days, the name applied by the ancients to a period of about forty days, the hottest season of the year, at the time of the heliacal rising of Sirius, the dog-star.

From The New Gresham Encyclopedia Volume 4, Part 1: Deposition to Eberswalde by Various