Navigator Star finder is a Java applet that shows the visible sky in any position, at any time. The chart is a polar representation where the angle represents the azimuth and the distance from the edge is the altitude of the celestial body.

By pointing a celestial body with the mouse, a "hint" will show with basic nautical almanac data (GHA, declination, right ascension, instrumental altitude and azimuth).

Click here to go to the star finder


Putting the star finder in your website

A number of people asked me if they could put the star finder applet in their website. The answer is yes! But putting the applet alone in your website directory will not work because this applet communicates with a CGI that does all the celestial calculations. And this CGI is specific to my webserver. Will probably not work in your ISP server anyway.

But I have made it simple to setup a link that displays the sky in a given position and current time. Suppose your city is located at latitude 23°30'S and longitude 46°30' W. The link would look like this:

<a href="">The sky over São Paulo, now</a>


  1. Lat and Lon should be numbers in real format (not degree/minutes format). In the example, we set lat = -23.5 (negative values for South) and lon = 46.5 (negative values for East).
  2. The link must be in the format .Current GMT time will be used.
  3. The only credits added in the response pages are my e-mail address and a link to the Navigator homepage. No advertising banners will be added in this page.