Introduction

Main Input Screen

Body Selector Window

Calendar and Print Options

Sunrise, Sunset, and LAN

Moonrise and Moonset

Accuracy and References

Arc to Time Table

StarPilot Programs

Main Input Window

This is the main window of the program, from here you select whether you want Ephemeris data (GHA and Declination) or Rise and Set data and also enter the time and date for any computation.

To find GHA and Declination
first select the body of interest by pressing the arrow next to the Body input. That will bring up the Body Selector screen.

Time input
All times are in GMT, which is the same as UT listed in the Nautical Almanac. You can type in the hr min and sec, or place the cursor on the one you wish to change and then use the up and down arrows beside it to change values.

Date input
Likewise with the date, you can type in the values, or click the down arrow for a convenient calendar display.

Then press Compute
to get these results:

GHAA =

GHA =

DEC =

SHA =

SD =

HP =

Mag =

Greenwich Hour Angle of Aries

Greenwich Hour Angle of the selected body

Declination of the selected body

Sidereal Hour Angle of the selected body

Semi-diameter of the body if sun or moon

Horizontal Parallax of the moon

Magnitude of a star or planet.

 

Print output
Press the Print button to view the Printing Options, which can be the screen output alone, or any sequence of data starting with this date and time. You select the time interval and the number of data points.

Rise and set data
select the sun icon for Sun data or the moon icon for Moon data after selecting time, date and latitude (Lat).

Twilight data
is obtained from the sun rise and set screen, which includes civil and nautical twilight times as well as the GHA of Aries at the midpoint between them.

LAN data (local apparent noon)
The time of meridian passage, peak height of the sun, and the Equation of Time are available in the sunrise and set data.

Latitude input
The Lat input is only used for the rise and set data for sun and moon, as well as Hc at LAN and the bearing of sun rise and set. Type in the latitude of interest and then select N or S. You can use whole degrees and minutes or decimal values; in any event the sum will be computed and presented in the output screen.

Help file
Click the Help button on any screen to open this Help file.