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The LHA Aries Calculator

LHA Aries LST calculator

The calculator is a circular slide rule computing the Local Hour Angle (LHA) of the Aries easily and quickly. The Local Sidereal Time is the same quantity except for the unit.
The templates and instructions for use are in a PDF file by "United States Power Squadrons".

Compute the LHA Aries on Mar 06 at 22:00 Standard Time for a location at 13.4° East (Berlin).
1. Align 00 hours on the hour scale with the date (Mar 6).
2. Align zone (standard) time (22:00) with the zone meridian (ZM).
3. Calculate the deviation from zone meridian (1.6° W = 13.4° E - 15° E).
4. Read LHA Aries at 1.6° E. Result: 133°.

To convert the LHA of Aries to Local Sidereal Time align 00h on the hour scale with 0° LHA and read the LST opposite LHA Aries. Result: 8h 52min.

The result of my Elevation and Azimuth Applet (in 2009) is 133.1°

applet elevation azimuth

Web Links

The USPS® LHA Aries Calculator (PDF)