VISWANATHAN , Vishnu

The main goal of the Ph.D. thesis of Vishnu Viswanathan was to improve the dynamical model of the Moon within the numerically integrated ephemeris (INPOP) and to derive results of scientific value from this improvement through the characterization of the lunar internal structure and tests of general relativity.At first, raw binaries of LLR...

We present here the new version of the INPOP planetary ephemerides based on an update of the observational data sets as well as new results in term of asteroid masses and constraints obtained for General relativity parameters PPN beta, gamma, J2 and the secular variations of G. New constraints about the hypothetical existence of a super-Earth...

Lunar laser ranging (LLR) data and Apollo seismic data analyses, revealed independent evidence for the presence of a fluid lunar core. However, the size of the lunar fluid core remained uncertain by $\pm55$ km (encompassing two contrasting 2011 Apollo seismic data analyses). Here we show that a new description of the lunar interior's dynamical...

When a light scalar field with gravitational strength interacts with matter, the weak equivalence principle is in general violated, leading for instance to a violation of the universality of free fall. This has been known and tested for a while. However, recent developments [Minazzoli & Hees, PRD 2016] showed that a novel manifestation of the...

In this poster we elaborate the use of raw navigation data (range and Doppler observations) from the Lunar Reconnaissance Orbiter (LRO) available on the Planetary Data System (PDS), in order to study the orbit of this probe using the orbit determination software (GINS) developed by the French space agency (CNES). The constraints that are...

LLR in IR (1064nm) gives an improvement in the temporal and spatial distribution of observations. Estimates of the lunar core using IR data will be presented.

No description

Since late 2014, OCA LLR station has been able to range with infrared wavelength (1064nm). IR ranging provides both temporal and spatial improvement in the LLR observations. IR detection also permits in densification of normal points, including the L1 and L2 retroreflectors due to better signal to noise ratio. This contributes to a better...

We present the results of the first series of successful two-way laser ranging experiments from a ground station, the Lunar Laser Ranging (LLR) station in Grasse, France, to a spacecraft at lunar distance, the Lunar Reconnaissance Orbiter (LRO). A 15 × 18 × 5 cm, 650-g array of twelve 32-mm diameter solid corner cubes is mounted on its...

The Lunar Laser Ranging (LLR) experiment has accumulated 50 years of range data of improving accuracy from ground stations to the laser retroreflector arrays (LRAs) on the lunar surface. The upcoming decade offers several opportunities to break new ground in data precision through the deployment of the next generation of single corner-cube...