Pascal Richard

Centre National d’Etudes Spatiales | CNES · DCT

The TAROT (Télescope à Action Rapide pour les Objets Transitoires –Rapid Action Telescope for Transient Objects) network of telescopes consists of two 25cm aperture telescopes located at the Calern Observatory(TCA, OCA, France), the La Silla Observatory (TCH, ESO, Chile), and a 18cm telescope at Les MakesObservatory, (TRE, France). In addition, we...

CNES and CNRS has been working on Optical Space Surveillance and Tracking for many years using the TAROT telescopes network. The goal of the study presented here is to propose an exhaustive strategy for optical survey of geosynchronous region. First, constraints will be defined on perigee and apogee of the orbits for which we are looking for exhaus...

One of the main missions of Space Surveillance is the detection and cataloguing of space objects. Maintenance of this catalogue is fundamental in order to enable the database to be used, among others, for collision risk assessment and reentry analysis. This maintenance comprises a twofold task. On one hand, it is necessary to keep track of known ob...

CNES is involved in the Inter-Agency Space Debris Coordination Committee (IADC) and is observing space debris with two robotic ground based fully automated telescopes called TAROT and operated by the CNRS. An image processing algorithm devoted to debris detection in geostationary orbit is implemented in the standard pipeline. Nevertheless, this alg...

In order to test a preliminary orbit determination method, we fit an orbit of the geostationary satellite TELECOM-2D, as if we did not know any a priori information on its trajectory. The method is based on a genetic algorithm coupled to an analytical propagator of the trajectory, that is used over a couple of days, and that uses a whole set of alt...

We present an orbit determination method based on genetic algorithms. Contrary to usual estimation methods mainly based on least-squares methods, these algorithms do not require any a priori knowledge of the initial state vector to be estimated. These algorithms can be applied when a new satellite is launched or for uncatalogued objects We show in...