Siderial is a Java program, it calculates the siderial time and value to select on the TAL scope RA scale. Just enter your local longitude (eastern longitudes are negative) and the RA hours and minutes of the star you want to look at. Click on the run button, or wait a few moments. The applet has a timer, which will update the calculated results - siderial time for GMT, for your local observation place, and the value to set on your TAL RA setting circle - every few seconds.

Requirements:
* Java

The license of this software is Freeware, you can free download and free use this calculator software.