Observing a GPS Satellite Maneuver with MW and SLR

Observing a GPS Satellite Maneuver with MW and SLR Astronomical Institute, University of Bern Claudia Urschl

Experiment history Maneuver for GPS satellite GPS35 • Maneuver announced for May 17, 2005 between 20:30 - 08:10 UT • Request for tracking via e-mail to SLR stations (ilrssta) • Maneuver took place at 22:28 UT • Bad weather conditions • Only Herstmonceux (7840) tracked GPS35 during the maneuver • Fullrate data (148) 22:11 – 23:08 UT Astronomical Institute, University of Bern

First orbit solution Maneuver at 22:28:17 Astronomical Institute, University of Bern

First orbit solution (zoom) Maneuver Astronomical Institute, University of Bern

Ground track GPS35 KIRU 7840 CHUR GOPE Maneuver KOUR Astronomical Institute, University of Bern

First orbit solution Dt = 234 s Astronomical Institute, University of Bern

Improved orbit Maneuver Astronomical Institute, University of Bern

Maneuver evaluation Orbit determination: a = 0.88 mm/s2 Dt = 234 s Assumption: m = 975 kg vGAS = 200 m/s Dv = 0.2 m/s F = 0.86 N MGAS = 1 kg Dv = a • Dt F = m • a MGAS = Dv / vGAS • m Astronomical Institute, University of Bern

GPS Satellite Maneuvers since 2004 May 17 Astronomical Institute, University of Bern

Observing a GPS Satellite Maneuver with MW and SLR