Welcome to Cygnus

Cygnus is a desktop application for generating precise ephemerides: tables and plots of where the celestial bodies are, sampled at a fixed interval across a date range you choose. It covers the geocentric, topocentric, and heliocentric perspectives, and for each of them it offers a positional ephemeris, an aspect ephemeris that also tracks the angles between pairs of bodies, and a graphic ephemeris that plots the same data as time-series curves.

Work in Cygnus is organized into studies. A study is one configured question: a place, a reference system, a span of time, a sampling interval, a set of celestial bodies, and the measurements you want reported for them. Studies live together in a workspace, which you save to a .cygnus file and reopen whenever you want to generate the same set of questions again. Most users work at an interval of 1 day, which produces one record per day across the whole span.

Cygnus is built for astrologers, astronomers, and hobbyists who need dependable planetary position data for personal research, learning, or observation planning. It assumes you are comfortable with terms like geocentric, ecliptic longitude, and declination, and it stays out of your way: distances are reported in AU and speeds in degrees per day, generated records can be copied straight into a document or spreadsheet, and every table can be exported to CSV.

What You Can Do with Cygnus

Each area of the application has its own section in this guide:

• Find your way around the application: the menu bar, the toolbar, the status indicators, and the Studies list. See Main Window.
• Keep your work in a workspace: create, open, and save the .cygnus files that hold your studies. See Workspace Management.
• Build up a set of studies: add studies to the workspace, duplicate them, remove them, and put them in the order you want. See Study Management.
• Configure a study before generating it: its name, location and reference system, date range and interval, celestial bodies, measurements, and the presets that reuse those choices. See Study Configuration.
• Generate the records: turn the configured parameters into data, and stop a generation that is taking longer than you expected. See Study Execution.
• Work with the ephemeris table: read it, arrange its columns, jump to a date, copy rows to the clipboard, and export to CSV. See Working with Records.
• Work with the graph: read values off the curves, adjust a value axis, and pan or zoom the time window. See Working with Graphs.
• Tabulate positions: the geocentric, topocentric, and heliocentric positional study types. See Standard Ephemerides.
• Track angular relationships: the three study types that record the angles between pairs of bodies alongside their positions. See Aspect Ephemerides.
• Plot motion over time: the three study types that draw curves instead of tables. See Graphic Ephemerides.
• Maintain your reference data and settings: your list of locations, the defaults new workspaces and studies start from, and the color assigned to each body on a graph. See Reference Data & Settings.
• Check your version and reach support: the About Dialog, the online documentation, and the update notification. See Help.

Where to Start

If you are new to Cygnus, the shortest path to your first ephemeris is:

1. Add a location in the Locations Editor, because every study needs one.
2. Create a study of the type you want from the Ephemerides menu.
3. Set its date range and interval, and check the bodies and measurements you want.
4. Click the Run button to generate the records.

Getting Help

• Choose Help → Documentation in Cygnus to open this documentation in your web browser. See Open Documentation.
• Choose Help → About Dialog to check which version you are running and the status of your license. Quote the version number when you report a problem. See About Dialog.
• When a newer version of Cygnus is available, a download button appears at the top right of the main window. See Update Notification.