Step 12 - The Local Sidereral Time

Element	_Symbol	Value
Epoch	t_o	05:54:21.171 UTC December 16, 2007
Inclination	i	51^o.9970
R.A. of the Ascending Node	a_W₀	251^o.0219
Eccentricity	e	0.0001492
Argument of Perigee	w₀	33^o.8641
Mean Anomaly at TLE Epoch	M_o	326^o.2322
Mean Motion	n	12.62256095 orbits / solar day
Propagation Time	Dt	1.7677141 solar days
Mean Anomaly at Time t	M(t)	1.37777389 radians (78^o.940629)
True Anomaly at Time t	n(t)	78^o.95065818
Semi-major Axis	a	7791.787473 km
Perigee Distance	P	7790.624938 km
Geocentric Distance	r(t)	7791.564499 km
Precessed R.A. of Asc. Node	a_W(t)	245^o.6400244
Precessed Arg. of Perigee	w(t)	37^o.77767416
Argument of Latitude	m(t)	116^o.7283323
R.A. Difference	Da	129^o.278845
Geocentric R.A.	a_g	14^o.9188694
Geocentric Declination	d_g	+44^o.73125163
Geocentric Cartesian x	x_g	5348.663965 km
Geocentric Cartesian y	y_g	1425.05581 km
Geocentric Cartesian z	z_g	5483.565179 km
Observer Geodetic Longitude	q	-75^o.6883
Observer Geodetic Latitude	l	+44^o.5903
Observer Geocentric Dec.	d_i	+44^o.5903

Next, we will require the Local Sidereal Time (a_i) observed at the chosen location at Time t. You can determine this value with most planetarium software or using the Internet. When entering your longitude in any sidereal time calculators, be very careful of the convention used!

The Geocentric Right Ascension of the observing location is its Local Sidereal Time at Time t. In this example:

a_i(t) = 15^o.419875

BACK TO STEP #11

PROCEED TO STEP #13

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Step 12: Local Sidereal Time Was Last Modified On April 01, 2014