IAG-IASPEI 2017

講演情報

Oral

IAG Symposia » G07. Global Geodetic Observing System (GGOS) and Earth monitoring services

[G07-2] GGOS focus on reference frames

2017年8月3日(木) 16:30 〜 18:00 Room 502 (Kobe International Conference Center 5F, Room 502)

Chairs: Detlef Angermann (Technical University of Munich) , Richard Gross (Jet Propulsion Laboratory, California Institute of Technology)

17:30 〜 17:45

[G07-2-05] Effective expansion of satellite laser ranging network for improving geodetic products and satellite orbits

Toshimichi Otsubo1, Koji Matsuo2, Yuichi Aoyama3, Keiko Yamamoto4, Thomas Hobiger5, Toshihiro Kubo-oka6, Mamoru Sekido6, Urs Hugentobler7, Rolf Koenig8 (1.Hitotsubashi University, Kunitachi, Japan, 2.Geospatial Information Authority of Japan, Tsukuba, Japan, 3.National Institute of Polar Research, Tachikawa, Japan, 4.National Astronomical Observatory of Japan, Mitaka, Japan, 5.Chalmers University of Technology, Gothenburg, Sweden, 6.National Institute of Information and Communications Technology, Kashima, Japan, 7.Technical University of Munich, Munich, Germany, 8.Deutsches GeoForschungsZentrum, Wessling, Germany)

About 35 satellite laser ranging stations are being operational all over the world but huge regions on the globe are not covered. We assume a new station is going to be added to the existing station network and therefore we like to evaluate the effectiveness of each location. Realistic numbers of observations for a new station are numerically simulated, based on the actual data acquisition statistics of the existing stations. Multiple-satellite-combined orbit determination is then conducted with and without a new station, and the estimated errors are investigated.

A new station placed in the Southern hemisphere is found to be effective in general. It is revealed that the most effective place differs according to the geodetic parameter. The X and Y components of the geocenter and the sectoral terms of the Earth's gravity field are largely improved by a station in the polar regions. A middle latitude station best contributes to the tesseral gravity terms, and, to a lesser extent, a low latitude station best performs for the Z component of the geocenter and the zonal gravity terms. With the existing stations the quality of satellite orbits is found to be relatively poor in the Southern hemisphere, but a new high latitude station in Antarctica enhances locally the accuracies so they behave close to uniform over one orbit.