activity
20182026
most citedA quasi-physical dynamic reduced order model for thermospheric mass density via Hermitian Space Dynamic Mode Decomposition

50 citations · 263 across the 24 of their papers we have counts for

collaborators

25 papers

eess.SY2026

Fast and Stable Nonlinear Emulation of TIEGCM Using an Autoregressive SINDy Framework

Daniele Sicoli, Sriram Narayanan, Piyush M. Mehta

The ever-growing number of satellites and resident space objects in low Earth orbit keeps increasing the risk of collision between these objects. To mitigate this risk, the develop…

eess.SY2026

Reduced-Order Data Assimilation for Thermospheric Density Using Physics-informed SINDyc Models

Sriram Narayanan, Daniele Sicoli, Piyush Mehta

Orbit prediction and space situational awareness require accurate thermospheric mass density, which responds nonlinearly to solar and geomagnetic forcing across several orders of m…

cs.CV2025

Spectral and Spatial Graph Learning for Multispectral Solar Image Compression

Prasiddha Siwakoti, Atefeh Khoshkhahtinat, Piyush M. Mehta +3

High-fidelity compression of multispectral solar imagery remains challenging for space missions, where limited bandwidth must be balanced against preserving fine spectral and spati…

eess.IV2024

Neural-based Video Compression on Solar Dynamics Observatory Images

Atefeh Khoshkhahtinat, Ali Zafari, Piyush M. Mehta +4

NASA's Solar Dynamics Observatory (SDO) mission collects extensive data to monitor the Sun's daily activity. In the realm of space mission design, data compression plays a crucial…

eess.IV2024

Laplacian-guided Entropy Model in Neural Codec with Blur-dissipated Synthesis

Atefeh Khoshkhahtinat, Ali Zafari, Piyush M. Mehta +1

While replacing Gaussian decoders with a conditional diffusion model enhances the perceptual quality of reconstructions in neural image compression, their lack of inductive bias fo…

eess.IV2023★ 7 cited

Neural-based Compression Scheme for Solar Image Data

Ali Zafari, Atefeh Khoshkhahtinat, Jeremy A. Grajeda +6

Studying the solar system and especially the Sun relies on the data gathered daily from space missions. These missions are data-intensive and compressing this data to make them eff…

eess.IV2023

Multi-spectral Entropy Constrained Neural Compression of Solar Imagery

Ali Zafari, Atefeh Khoshkhahtinat, Piyush M. Mehta +4

Missions studying the dynamic behaviour of the Sun are defined to capture multi-spectral images of the sun and transmit them to the ground station in a daily basis. To make transmi…

eess.IV2023★ 1 cited

Multi-Context Dual Hyper-Prior Neural Image Compression

Atefeh Khoshkhahtinat, Ali Zafari, Piyush M. Mehta +3

Transform and entropy models are the two core components in deep image compression neural networks. Most existing learning-based image compression methods utilize convolutional-bas…

eess.IV2023

Context-Aware Neural Video Compression on Solar Dynamics Observatory

Atefeh Khoshkhahtinat, Ali Zafari, Piyush M. Mehta +4

NASA's Solar Dynamics Observatory (SDO) mission collects large data volumes of the Sun's daily activity. Data compression is crucial for space missions to reduce data storage and v…

eess.IV2023★ 11 cited

Frequency Disentangled Features in Neural Image Compression

Ali Zafari, Atefeh Khoshkhahtinat, Piyush Mehta +3

The design of a neural image compression network is governed by how well the entropy model matches the true distribution of the latent code. Apart from the model capacity, this abi…

physics.space-ph2023★ 2 cited

Probabilistic Solar Proxy Forecasting with Neural Network Ensembles

Joshua D. Daniell, Piyush M. Mehta

Space weather indices are used commonly to drive forecasts of thermosphere density, which directly affects objects in low-Earth orbit (LEO) through atmospheric drag. One of the mos…

physics.space-ph2022★ 18 cited

Reduced Order Probabilistic Emulation for Physics-Based Thermosphere Models

Richard J. Licata, Piyush M. Mehta

The geospace environment is volatile and highly driven. Space weather has effects on Earth's magnetosphere that cause a dynamic and enigmatic response in the thermosphere, particul…

physics.space-ph2022★ 2 cited

Advanced ensemble modeling method for space object state prediction accounting for uncertainty in atmospheric density

Smriti Nandan Paul, Richard J. Licata, Piyush M. Mehta

For objects in the low Earth orbit region, uncertainty in atmospheric density estimation is an important source of orbit prediction error, which is critical for space situational a…

physics.space-ph2022★ 1 cited

Stochastic modeling of physical drag coefficient -- its impact on orbit prediction and space traffic management

Smriti Nandan Paul, Phillip Logan Sheridan, Richard J. Licata +1

Ambitious satellite constellation projects by commercial entities and the ease of access to space in recent times have led to a dramatic proliferation of low-Earth space traffic. I…

eess.IV2022★ 10 cited

Attention-Based Generative Neural Image Compression on Solar Dynamics Observatory

Ali Zafari, Atefeh Khoshkhahtinat, Piyush M. Mehta +4

NASA's Solar Dynamics Observatory (SDO) mission gathers 1.4 terabytes of data each day from its geosynchronous orbit in space. SDO data includes images of the Sun captured at diffe…

physics.space-ph2022★ 1 cited

Understanding variability in HASDM to support space traffic management

W. Kent Tobiska, Marcin D. Pilinski, Shaylah Mutschler +5

With more commercial constellations planned, the number of Low Earth Orbit (LEO) objects is set to TRIPLE in two years. The growth in LEO objects directly increases the probability…

physics.space-ph2022★ 22 cited

Calibrated and Enhanced NRLMSIS 2.0 Model with Uncertainty Quantification

Richard J. Licata, Piyush M. Mehta, Daniel R. Weimer +2

The Mass Spectrometer and Incoherent Scatter radar (MSIS) model family has been developed and improved since the early 1970's. The most recent version of MSIS is the Naval Research…

physics.space-ph2022★ 17 cited

Science through Machine Learning: Quantification of Poststorm Thermospheric Cooling

Richard J. Licata, Piyush M. Mehta, Daniel R. Weimer +3

Machine learning (ML) is often viewed as a black-box regression technique that is unable to provide considerable scientific insight. ML models are universal function approximators…

cs.LG2022★ 3 cited

Uncertainty Quantification Techniques for Space Weather Modeling: Thermospheric Density Application

Richard J. Licata, Piyush M. Mehta

Machine learning (ML) has often been applied to space weather (SW) problems in recent years. SW originates from solar perturbations and is comprised of the resulting complex variat…

physics.space-ph2021★ 30 cited

The current state and future directions of modeling thermosphere density enhancements during extreme magnetic storms

Denny M. Oliveira, Eftyhia Zesta, Piyush M. Mehta +4

Satellites, crewed spacecraft and stations in low-Earth orbit (LEO) are very sensitive to atmospheric drag. A satellite's lifetime and orbital tracking become increasingly inaccura…

cs.LG2021★ 3 cited

Machine-Learned HASDM Model with Uncertainty Quantification

Richard J. Licata, Piyush M. Mehta, W. Kent Tobiska +1

The first thermospheric neutral mass density model with robust and reliable uncertainty estimates is developed based on the SET HASDM density database. This database, created by Sp…

physics.space-ph2020★ 45 cited

Benchmarking Forecasting Models for Space Weather Drivers

Richard J. Licata, W. Kent Tobiska, Piyush M. Mehta

Space weather indices are commonly used to drive operational forecasts of various geospace systems, including the thermosphere for mass density and satellite drag. The drivers serv…

physics.space-ph2018★ 3 cited

Data-driven framework for real-time thermospheric density estimation

Piyush M. Mehta, Richard Linares

In this paper, we demonstrate a new data-driven framework for real-time neutral density estimation via model-data fusion in quasi-physical ionosphere-thermosphere models. The frame…

physics.ao-ph2018★ 37 cited

A new transformative framework for data assimilation and calibration of physical ionosphere-thermosphere models

Piyush M. Mehta, Richard Linares

Accurate specification and prediction of the ionosphere-thermosphere (IT) environment, driven by external forcing, is crucial to the space community. In this work, we present a new…