Ad Astra Observatory

where do all the constants come from?

// test
function test()
{
// Pleiades M45, 03h47.0m, +24�07′
// Boston, MA US 42�21′ N, 71�04′ W

// UTC: 04/07/2004 01:00:00
// alt = 21.0656�, az = 283.967�

// Right Ascension
calc.ra_hours.value = “03”;
calc.ra_minutes.value = “47.0”;

// Declination
calc.dec_degrees.value = “24”;
calc.dec_minutes.value = “07.0”;

// Latitude

calc.lat_degrees.value = “42”;
calc.lat_minutes.value = “21.0”;

// Longitude
calc.lon_degrees.value = “-71”;

calc.lon_minutes.value = “04.0”;

// use local computer time to get UTC: 04/07/2004 01:00:00
calc.dtg_year.value = 2004
calc.dtg_month.value = 4
calc.dtg_day.value = 6

calc.dtg_hour.value = 21
calc.dtg_minute.value = 0
calc.dtg_second.value = 0
}

// compute altitude and azimuth
function compute()
{

var dec_degrees = parseInt(calc.dec_degrees.value, 10);
var dec_minutes = parseInt(calc.dec_minutes.value, 10);
var ra_hours = parseInt(calc.ra_hours.value, 10);
var ra_minutes = parseInt(calc.ra_minutes.value, 10);
var lat_degrees = parseInt(calc.lat_degrees.value, 10);
var lat_minutes = parseInt(calc.lat_minutes.value, 10);

var lon_degrees = parseInt(calc.lon_degrees.value, 10);
var lon_minutes = parseInt(calc.lon_minutes.value, 10);
var dtg_year = parseInt(calc.dtg_year.value, 10);
var dtg_month = parseInt(calc.dtg_month.value, 10);
var dtg_day = parseInt(calc.dtg_day.value, 10);
var dtg_hour = parseInt(calc.dtg_hour.value, 10);

var dtg_minute = parseInt(calc.dtg_minute.value, 10);
var dtg_second = parseInt(calc.dtg_second.value, 10);

if (isNaN(dec_degrees)