LEVASSEUR-REGOURD , Anny Chantal

Polarimetry is a very useful tool for asteroid studies because it makes it possible to get information on some important physical parameters, like geometric albedo, which are intimately related to surface composition and regolith structure. In recent years there has been a strongly renewed interest in the field of asteroid polarimetry, due to...

We have developed a new three-parameter H, G1, G2 magnitude phase function for asteroids. The phase function is aimed at replacing the currently adopted two-parameter H, G phase function. We show that H, G1, G2 produces better fits of available magnitude - phase curves of well-observed asteroids. We show also that the new system can be...

Although it cannot provide direct and unambiguous information on the mineralogical composition of an asteroid surface, polarimetry is a very useful tool to get an improved understanding of parameters which are intimately related to surface composition and regolith structure. In recent times there has been a revival in the field of asteroid...

We develop a three-parameter H, G1, G2 magnitude phase function for asteroids starting from the current two-parameter , H, G phase function. We describe stochastic optimization of the basis functions of the magnitude phase function based on a carefully chosen set of asteroid photometric observations covering the principal types of phase...

We present Markov-Chain Monte-Carlo methods (MCMC) for the derivation of empirical model parameters for photometric and polarimetric phase curves of asteroids. Here we model the two phase curves jointly at phase angles 25° using a linear-exponential model, accounting for the opposition effect in disk-integrated brightness and the negative...

New UBVRI polarimetric observations of ten asteroids, including space mission targets 1 Ceres and 21 Lutetia, are presented. These observations were obtained with the 1.25-m telescope of the Crimean Astrophysical Observatory and have been used to study the wavelength dependence of polarization for a sample of asteroids belonging to the M and...

Data System

Context. An assessment of the dust environment of a comet is needed for data analysis and planning spacecraft missions, such as ESA's Comet Interceptor (CI) mission. The distinctive feature of CI is that the target object will be defined shortly before (or even after) launch; as a result, the properties of the nucleus and dust environment are...

Assessment of the dust environment of a comet is needed for data analysis and planning of spacecraft missions, such as ESA's Comet Interceptor (CI) mission. The distinctive feature of CI is that the target object will be defined shortly before (or even after) launch therefore the properties of the nucleus and dust environment are poorly...

ASteroid Sounding Experiment by Radiowaves Transmission is a radar to instrument the Mascot lander which is proposed in the frame future Hayabusa 2 Jaxa mission. This low frequency radar is a unique opportunity to sound the internal structure of the target. It is to achieve the tomography both in transmission and in reflexion of the asteroid in...

Consert for Asteroid is a radar to instrument the Mascot lander, which is proposed in the frame of future Near Earth Asteroid missions. This low frequency radar is a unique opportunity to sound the internal structure of the target. Its objective is to achieve the tomography both in transmission and in reflexion of the asteroid in order to...

We describe the AMBITION project, a mission to return the first-ever cryogenically- stored sample of a cometary nucleus, that has been proposed for the ESA Science Programme Voyage 2050. Comets are the leftover building blocks of giant planet cores and other planetary bodies, and fingerprints of Solar System's formation pro- cesses. We...

We describe the AMBITION project, a mission to return the first-ever cryogenically- stored sample of a cometary nucleus, that has been proposed for the ESA Science Programme Voyage 2050. Comets are the leftover building blocks of giant planet cores and other planetary bodies, and fingerprints of Solar System's formation pro- cesses. We...

Amateur contributions to professional publications have increased exponentially over the last decades in the field of Planetary Astronomy. Here we review the different domains of the field in which collaborations between professional and amateur astronomers are effective and regularly lead to scientific publications. We discuss the instruments,...

The Stardust mission returned cometary, interplanetary and (probably) interstellar dust in 2006 to Earth that have been analysed in Earth laboratories worldwide. Results of this mission have changed our view and knowledge on the early solar nebula. The Rosetta mission is on its way to land on comet 67P/Churyumov-Gerasimenko and will investigate...

Our knowledge of the internal structure of asteroids is, so far, indirect – relying entirely on inferences from remote sensing observations of the surface, and theoretical modeling of formation and evolution. What are the bulk properties of the regolith and deep interior? And what are the physical processes that shape asteroid internal...