<h2>AAS 95-368</h2><h2>TOPEX/Poseidon Precision Orbit Determination:   "Quick-Look" Operations with GPS and SLR Data</h2><h4>L. A. Cangahuala,  R. J. Muellerschoen, D. N. Yuan, E. J. Christensen, E. J. Graat and J. R. Guinn, Jet Propulsion Laboratory, Pasadena, CA</h4><h2> Abstract </h2>This paper presents a summary of the TOPEX/Poseidon "quick-look" orbit determination using Global Positioning System (GPS) and satellite laser ranging (SLR) tracking data.  The primary feature of this endeavor is that orbits are produced with small radial position errors (< 5 cm RMS), on a short production schedule (< 4 days), with minimal resources.

With the two data types, there are five data combination scenarios which occur during operations: (i) GPS (w/Anti-Spoofing) & SLR, (ii) GPS (w/o Anti-Spoofing) & SLR, (iii) GPS (w/ Anti-Spoofing), (IV) GPS (w/o Anti Spoofing), and (v) SLR only.  Orbits created under all five scenarios are compared to existing precision orbit ephemerides to demonstrate their relative accuracy as an orbit product.<br><br>