heliacal

In about a month, followed the Stars of the Husbandman; the chief of them, Ras, Mirach, and Arcturus, being very nearly simultaneous in their heliacal rising.

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

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 Mary Somerville

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 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 Edward Huntington Williams

They approximated to the truth in reference to the solar year, by observing the equinoxes and solstices, and the heliacal rising of particular stars.

From The Old Roman World, : the Grandeur and Failure of Its Civilization. by John Lord