A
Two-Line Element Set (TLE) is a way of encoding orbital elements of Earth-orbiting objects at a given time. This is the format
NORAD provides data on many satellites in space right now. It'd be nice to see that as a 3d visualization. We use python to parse text files pulled from NORAD, and plot with
matplotlib.
|
Military satellite orbits |
For example the TLE for SpaceX's Dragon spacecraft during the CRS-2 mission was
dragon = """DRAGON CRS-2
1 39115U 13010A 13062.62492353 .00008823 00000-0 14845-3 0 188
2 39115 51.6441 272.5899 0012056 334.2535 68.5574 15.52501943 306"""
orbit.py contains the code to parse the TLE into components as well as call graphics to draw it.
print "Satellite Name = %s" % title
print "Satellite number = %g (%s)" % (satellite_number, "Unclassified" if classification == 'U' else "Classified")
print "International Designator = YR: %02d, LAUNCH #%d, PIECE: %s" % (international_designator_year, international_designator_launch_number, international_designator_piece_of_launch)
print "Epoch Date = %s (YR:%02d DAY:%.11g)" % (epoch_date.strftime("%Y-%m-%d %H:%M:%S.%f %Z"), epoch_year, epoch)
print "First Time Derivative of the Mean Motion divided by two = %g" % first_time_derivative_of_the_mean_motion_divided_by_two
print "Second Time Derivative of Mean Motion divided by six = %g" % second_time_derivative_of_mean_motion_divided_by_six
print "BSTAR drag term = %g" % bstar_drag_term
print "The number 0 = %g" % the_number_0
print "Element number = %g" % element_number
print
print "Inclination [Degrees] = %g°" % inclination
print "Right Ascension of the Ascending Node [Degrees] = %g°" % right_ascension
print "Eccentricity = %g" % eccentricity
print "Argument of Perigee [Degrees] = %g°" % argument_perigee
print "Mean Anomaly [Degrees] Anomaly = %g°" % mean_anomaly
print "Eccentric Anomaly = %g°" % eccentric_anomaly
print "True Anomaly = %g°" % true_anomaly
print "Mean Motion [Revs per day] Motion = %g" % mean_motion
print "Period = %s" % timedelta(seconds=period)
print "Revolution number at epoch [Revs] = %g" % revolution
print
print "semi_major_axis = %gkm" % semi_major_axis
print "eccentricity = %g" % eccentricity
print "inclination = %g°" % inclination
print "arg_perigee = %g°" % argument_perigee
print "right_ascension = %g°" % right_ascension
print "true_anomaly = %g°" % true_anomaly
|
Dragon CRS-2 and ISS space station |