Heliacal Phenomenon Study

The Heliacal Phenomenon Study generates events for the heliacal risings and settings of celestial bodies. A heliacal rising occurs when a star or planet becomes visible again in the eastern sky just before sunrise after a period of being hidden by the Sun's glare. A heliacal setting occurs when a star or planet is seen for the last time in the western sky just after sunset before disappearing into the Sun's glare for a period of invisibility.

Create a Heliacal Phenomenon Study

To add a new Heliacal Phenomenon Study to the active workspace:

1. Click Mundane Studies on the menu bar.
2. Click Declination Studies, then click Heliacal Phenomenon in the submenu.

tip

You can also create a Heliacal Phenomenon Study from the toolbar by clicking the Declination Studies drop-down button and selecting Heliacal Phenomenon.

Events Captured

A Heliacal Phenomenon event marks the first or last visibility of a body in proximity to the Sun. The Event Type column distinguishes between the heliacal phenomenon types Aquila supports (e.g., heliacal rising, heliacal setting, evening rising). Each event includes the body's position, the Sun's position, and the local Ascendant and Descendant at the moment of visibility.

Events Table Columns

The events table for a Heliacal Phenomenon Study contains the following columns:

Column	Description
Date Time	Date and time of the heliacal phenomenon event.
Event Type	Type of heliacal phenomenon (e.g., heliacal rising, heliacal setting, evening rising).
Body	Name of the body undergoing the heliacal phenomenon.
Body Longitude	Ecliptic longitude (or right ascension) of the body at the event.
Body Sign	Zodiac sign (with degrees) of the body.
Body Latitude	Ecliptic latitude (or declination) of the body.
Body Distance	Distance of the body from the coordinate origin.
Body Speed	Daily motion of the body.
Sun Longitude	Ecliptic longitude (or right ascension) of the Sun at the event.
Sun Sign	Zodiac sign (with degrees) of the Sun.
Ascendant Longitude	Ecliptic longitude (or right ascension) of the Ascendant at the location and time of the event.
Ascendant Sign	Zodiac sign of the Ascendant.
Descendant Longitude	Ecliptic longitude (or right ascension) of the Descendant.
Descendant Sign	Zodiac sign of the Descendant.
Event Interval	Time interval since the previous heliacal event.