Brief Bio

Dr. Vishnu Viswanathan’s research is focused on the analysis of tracking data to determine geophysical, orbital and rotational properties of planetary bodies. In 2017, Dr. Viswanathan improved the orbital-rotational dynamical model of the Moon and fitted it to over five decades of lunar laser ranging (LLR) data with gravity field constraints from the NASA GRAIL mission. This model is one of the primary references in the world that provides high-precision planetary and lunar ephemerides. In 2018, Dr. Viswanathan used this model to perform a fundamental physics test of the universality of free fall using the Earth-Moon system as test bodies, improving upon previous constraints on the principle of equivalence. In 2019, Dr. Viswanathan further expanded the capabilities of this model that resulted in the strongest constraint known for the shape and size of the lunar core-mantle boundary. Dr. Viswanathan also revealed an anomalous lunar interior signature present in the lunar rotational motion as tracked by LLR data, which remains a topic of active research within the LLR community. In 2020, Dr. Viswanathan published two white papers submitted to the Committee on the Planetary Science Decadal Survey (2023-2032) of the National Academies of Sciences/USA, and to the Artemis III Science Definition Team, representing the interests, objectives and goals of the global LLR instrument, data analysis and observer community.

Dr. Viswanathan is currently at NASA GSFC employed by UMBC under the CRESST II cooperative agreement, advised by Dr. Erwan Mazarico.

Research Interests

Positions/Employment

Education

Ph.D. 2017, Astronomy and Astrophysics, Observatoire de Paris - France, "Improving the dynamical model of the Moon using lunar laser ranging (LLR) and spacecraft data", Supervisors: Prof. Agnès Fienga and Prof. Jacques Laskar

M.S. 2013, Space Systems Engineering, Institut Supérieur de l'Aéronautique et de l'Espace, Toulouse - France, "Emulation of a geostationary channel using software-defined radio platform", Supervisor: Prof. Laurent Franck

B.Tech. 2011, Electronics and Communication Engineering, National Institute of Technology, Trichy - India

Professional Societies

Professional Service

Reviewer for ApJL, A&A, ASR, ESS, JGeod, Universe

Panelist for NASA ROSES

Grants

Publications

Refereed

Mazarico, E., X. Sun, J.-M. Torre, et al. C. Courde, J. Chabé, M. Aimar, H. Mariey, N. Maurice, M. K. Barker, D. Mao, D. R. Cremons, S. Bouquillon, T. Carlucci, V. Viswanathan, F. G. Lemoine, A. Bourgoin, P. Exertier, G. A. Neumann, M. T. Zuber, and D. E. Smith. 2020. "First Two-way Laser Ranging to a Lunar Orbiter: infrared observations from the Grasse station to LRO’s retro-reflector array ." Earth, Planets and Space, [Full Text (Link)] [10.1186/s40623-020-01243-w]

Viswanathan, V., N. Rambaux, A. Fienga, J. Laskar, and M. Gastineau. 2019. "Observational constraint on the radius and oblateness of the lunar core-mantle boundary." Geophysical Research Letters, 46: [10.1029/2019GL082677]

Viswanathan, V., A. Fienga, O. Minazzoli, et al. L. Bernus, J. Laskar, and M. Gastineau. 2018. "The new lunar ephemeris INPOP17a and its application to fundamental physics." Monthly Notices of the Royal Astronomical Society, 476: 1877-1888 [10.1093/mnras/sty096]

Courde, C., J. M. Torre, E. Samain, et al. G. Martinot-Lagarde, M. Aimar, D. Albanese, P. Exertier, A. Fienga, H. Mariey, G. Metris, H. Viot, and V. Viswanathan. 2017. "Lunar laser ranging in infrared at the Grasse laser station." Astronomy & Astrophysics, 602: A90 [10.1051/0004-6361/201628590]

Non-Refereed

Ermakov, A., J. C. Castillo-Rogez, R. S. Park, et al. C. Sotin, J. Lazio, S. M. Howell, J. T. Keane, D. J. Hemingway, F. Nimmo, E. Kite, V. Viswanathan, G. Steinbrügge, G. Tobie, and V. Lainey. 2021. "A Recipe for Geophysical Exploration of Enceladus." Bulletin of the American Astronomical Society 53 (4): [10.3847/25c2cfeb.b65f2c4c]

Viswanathan, V., E. Mazarico, S. Merkowitz, et al. J. G. Williams, S. G. Turyshev, D. G. Currie, A. I. Ermakov, N. Rambaux, A. Fienga, C. Courde, J. Chabé, J.-M. Torre, A. Bourgoin, U. Schreiber, T. M. Eubanks, C. Wu, D. Dequal, S. Dell'Agnello, L. Biskupek, J. Müller, and S. Kopeikin. 2021. "Extending Science from Lunar Laser Ranging." Bulletin of the American Astronomical Society 53 (4): [10.3847/25c2cfeb.3dc2e5e4]

Viswanathan, V., A. Fienga, M. Gastineau, and J. Laskar. 2017. "INPOP17a planetary ephemerides." Notes Scientifiques et Techniques de l'Institut de mécanique céleste S108: ISBN: 2-910015-79-3. [Full Text (Link)] [10.13140/RG.2.2.24384.43521]

Courde, C., J.-M. Torre, E. Samain, et al. G. Martinot-Lagarde, M. Aimar, D. Albanese, N. Maurice, H. Mariey, H. Viot, P. Exertier, A. Fienga, and V. Viswanathan. 2017. "Satellite and lunar laser ranging in infrared." Proceedings of the SPIE Conference on Photon Counting Applications, 2017 10229: UNSP 102290K [10.1117/12.2270573]

Talks, Presentations and Posters

Invited

Other

Teaching Experience

"Principles of Thermodynamics", Undergraduate level, ESAIP Graduate School of Engineering, Grasse - France

"Satellite systems", Graduate level, University of Nice, Sophia Antipolis

 

Selected Public Outreach