EXERTIER , P.

The Earth is a specific body in the Universe. Nowadays, thanks to the high accuracy of the measurements obtained by different techniques of geodesy, its shape, as well as its gravity field, can be described and characterized in a very precise way, with thousands of parameters: the Earth is a spherical body only in a very first approximation!

The T2L2 project (time transfer by laser link) allows for the synchronization of remote ultra-stable clocks over intercontinental distances (Fridelance et al 1997 Exp. Astron. 7, Samain and Fridelance 1998 Metrologia 35 151–9). The principle is derived from satellite laser ranging technology with dedicated space equipment designed to record...

The T2L2 (Time Transfer by Laser Link) project, developed by CNES and OCA will permit the synchronization of remote ultra stable clocks and the determination of their performances over intercontinental distances. The principle of the experiment derives from Satellite Laser Ranging (SLR) technology with dedicated space equipment. T2L2 was...

A real alternative to Lagrange point very low perturbed orbits, for universe observation missions, is high eccentric Earth orbits. Combination of high eccentricity and very large semi-major axis leads to orbits with an important part of flight time far from Earth and its perturbations. Modeling this particular relative motion is the scoop of...

Advances in Space Research, v. 36, n. 3, p. 402-411, 2005. http://dx.doi.org/10.1016/j.asr.2005.04.056

The study of the relative motion between two very-close non-massive objects has been usually done through Hill equations. More recent approaches use the differences of orbital elements to extrapolate relative motion. In this paper, we present another possible representation of the relative motion. This representation takes advantage of the very...

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Celestial Mechanics and Dynamical Astronomy, v. 94, n. 1, p. 83-104, 2006. http://dx.doi.org/10.1007/s10569-005-1472-2

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The Corsica site has been established in 1996 to perform altimeter calibration on TOPEX/Poseidon and then on its successors Jason-1 and Jason-2. The first chosen location was under the #85 ground track that overflight the Senetosa Cape. In 2005, it was decided to develop another location close to Ajaccio, to be able to perform the calibration...

Initially developed for monitoring the performance of TOPEX/Poseidon and follow-on Jason legacy satellite altimeters, the Corsica geodetic facilities that are located both at Senetosa Cape and near Ajaccio have been developed to calibrate successive satellite altimeters in an absolute sense. Since 1998, the successful calibration process used...

The Corsica site has been established in 1996 to perform altimeter calibration on TOPEX/Poseidon and then on its successors Jason-1 and Jason-2. The first chosen location was under the #85 ground track that overflight the Senetosa Cape. In 2005, it was decided to develop another location close to Ajaccio, to be able to perform the calibration...

International audience

Marine Geodesy, v. 27, n. 3-4, p. 631-655, Special Issue on Jason-1 Calibration/Validation, 2004. http://dx.doi.org/10.1080/01490410490902106

The Corsica region of the western Mediterranean, including sites at Ajaccio-Aspretto, Cape Senetosa, and Capraia (Italy), hosts a dedicated, long-term experiment to support absolute calibration of space-borne radar altimeters. The objective of the experiment is to continuously monitor the bias and drift of the altimeter measurement systems. In...

The French Transportable Laser Ranging System (FTLRS) was deployed in the calibration site of satellite radar altimeters in Corsica over the 2002 and 2005 campaigns. The paper describes the different steps of SLR data processing. The average arcs RMS obtained are about 1-2 cm for Lageos-1&-2, Starlette and Stella satellites; it is shown that...

Marine Geodesy, v. 27, n. 1-2, p. 333-340, Special Issue on Jason-1 Calibration/Validation, 2004. http://dx.doi.org/10.1080/01490410490476272

In this paper, are given numerical estimations of the sensitivity of the latest version of the INPOP planetary ephemerides (INPOP13c) to GR parameters: the PPN parameters β, γ, and the oblateness of the Sun J⊙2. Time variations of the gravitational mass of the Sun μ are also considered. A first estimation is obtained by fitting these parameters...

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Recent studies show a change, starting in 1998, in the behavior of the variation of the dynamical flattening of the Earth (J2), supposed to be constant (secular), and mainly due to the post glacial rebound effect. In this paper, we study to what extent this behavior can be correlated or not with the 18.6 year tide: with more than twenty years...

The present study consists in studying the mean orbital motion of the CHAMP satellite, through a single long arc on a period of time of 200 days in 2001. We actually investigate the sensibility of its mean motion to its accelerometric data, as measures of the surface forces, over that period. In order to accurately determine the mean motion of...

The Time Transfer by Laser Link (T2L2) experiment has been developed in close collaboration between Centre National d'Etudes Spatiales and Observatoire de la Côte d'Azur. The aim is to synchronize remote ultra-stable clocks over large-scale distances using two laser ranging stations. This ground to space time transfer has been derived from...

The main applications for DORIS are precise orbit determination, and precise Geodesy. Onboard Jason-2 for instance, the DORIS tracking component is the French contribution to the precise orbit determination capability, a key capability for altimetry product scientific result accuracy. T2L2 is a time transfer technique based on the propagation...

The Time Transfer by Laser Link (T2L2) is a very high resolution time transfer technique based on the recording of arrival times of laser pulses at the satellite. T2L2 was designed to achieve time stability in the range of 1 ps over 1000 s and an accuracy better than 100 ps. The project is in operation onboard the Jason-2 satellite since June...

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