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

See Examples For:

heliacal rising

Sothic, sō′thik, adj. of or pertaining to the dog-star Sothis or Sirius.—Sothic cycle, or period, a period of 1460 years; Sothic year, the ancient Egyptian fixed year, according to the heliacal rising of Sirius.

From Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements) by Various

The first day of the Muhammadan month Jamada' l akhir, corresponding to the heliacal rising of the moon on that occasion, was Saturday, May 19.

From A Forgotten Empire (Vijayanagar): a contribution to the history of India by Sewell, Robert

This is what is technically known as the "acronical rising" of the Pleiades, their rising at sunset; in contrast to their "heliacal rising," their rising just before daybreak, which ushered in the spring time.

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

If therefore Ilioneus, according to our supposition, understand the heliacal rising of Orion, Anna must mean the achronical, which the different epithets given to that constellation seem to manifest.

From Discourses on Satire and on Epic Poetry by Dryden, John

Either the calendar did not originate in Egypt, or it was introduced in 2780 B.C., when again the heliacal rising Sothis fell on the first of Thoth.

From The Egyptian Conception of Immortality by Reisner, George Andrew