About Me

Hi! I'm Rohan Pattnaik, an astrophysicist and applied AI specialist with a unique journey bridging Computer Science and Astrophysics. My journey started with an undergraduate degree in Computer Science, where my curiosity for challenging problems sparked an interest in astrophysics—a field full of intriguing data and unique problems.

My Journey

My career path is rooted in curiosity and interdisciplinary exploration. I've had the privilege of working on fascinating problems, from analyzing astronomical data—like radio, X-ray, and optical spectra—to leveraging AI in industry sectors such as finance and energy. Each new domain has deepened my appreciation for data, reinforcing my belief that quality data is equally—if not more—crucial than sophisticated algorithms.

What I Do

I excel at rapidly immersing myself in new fields, understanding their core challenges, and determining precisely how AI can make a meaningful difference. My unique experience with unconventional datasets, like galaxy spectra, has equipped me with a distinctive approach to problem-solving. Currently, I'm actively involved in collaborations within astrophysics research, contributing insights that streamline and enhance traditional methodologies.

Let's Collaborate!

Today, I actively advise astronomy research projects worldwide, including collaborations spanning my past institutions. I’m always open to new challenges—especially those that require innovative, data-driven approaches that traditional consulting may not offer. Explore my Skills & Research page for deeper insights into my work and to see how my skills and experience might align with your projects. If you're interested in collaborating or have intriguing challenges you'd like to discuss, please reach out via the Contact page.

Skills Summary

Programming Languages

Python

C++

R

Julia

Java

C

Bash

SQL-lite

Tools

Pytorch

Pandas

Keras

Numpy

Scikit-Learn

Git

HTML5

CSS3

Latex


Research & Projects

SpecPT

SpecPT (Spectroscopy Pre-trained Transformer) Model for Galaxy Spectra

Spectroscopy Pre-trained Transformer (SpecPT) is a transformer-based model developed for analyzing spectroscopic data, including spectrum reconstruction and redshift estimation. Trained on the DESI Early Data Release (EDR), SpecPT demonstrates strong performance on both Bright Galaxy Survey (BGS) and Emission Line Galaxy (ELG) samples. It accurately reconstructs spectra—capturing emission lines, absorption features, and continuum shapes—while effectively denoising the input. For redshift prediction, SpecPT achieves high accuracy with with Normalized Median Absolute Deviation (NMAD) values of 0.0006 and 0.0008, and low catastrophic outlier fractions of 0.20% and 0.80%, respectively. It performs reliably across the full redshift range (0<z<1.6), highlighting its robustness. SpecPT's learned latent representations also enable downstream applications, such as outlier detection, ISM property estimation, and transfer learning across datasets.
[Paper Link]

SpecPT

Redshift Wrangler: Citizen Science Spectroscopy

Redshift Wrangler is a Zooniverse-based citizen science project that invites the public to help measure galaxy redshifts—key to understanding how galaxies evolve across cosmic time. By identifying spectral features in galaxy spectra, volunteers contribute to locating galaxies on the timeline of the universe. I developed a custom pipeline that converts raw FITS data into clean, interpretable images by dynamically adjusting contrast and brightness, enabling accurate public annotations. These labeled spectra serve as foundational training data for future machine learning models, enhancing both accuracy and interpretability through supervised and contrastive learning approaches.
[Check Out Redshift Wrangler on Zooniverse]

SpecPT

Classifying Low-Mass X-ray Binaries (LMXBs) using Machine Learning

Low-mass X-ray binaries (LMXBs) are binary systems where one of the components is either a black hole or a neutron star and the other is a less massive star. It is challenging to unambiguously determine whether an LMXB hosts a black hole or a neutron star. In the last few decades, multiple observational works have tried, with different levels of success, to address this problem. We developed a machine learning approach to classify LMXBs based on their compact object nature using a Random Forest classifier trained on 5-25 keV energy spectra from the RXTE archive, achieving ~87% classification accuracy. We further use the trained model for predicting the classes for LMXB systems with unknown or ambiguous classification. For more details check out our paper linked below.
[Paper Link]

SpecPT

Seasonal Model Robustness in Financial Forecasting

At J.P. Morgan, I worked on evaluating deposit forecast models used for regulatory compliance and risk management. A newly introduced X-13 model, while sophisticated, showed signs of overfitting on simpler data. I designed a custom cross-validation framework to assess model performance, which confirmed these concerns. My analysis led to retaining simpler, more stable models—improving forecast accuracy while reducing overfitting risk in a high-stakes financial environment.

SpecPT

ResNet-based Rock Particle Classification at SLB

At SLB, I enhanced rock particle classification by tackling bias introduced by heuristic labels that compromised model accuracy. First, I developed a secure, web-based image labeling app enabling field experts to annotate samples directly—improving label quality and enabling scalable dataset expansion. Using this improved dataset, I fine-tuned a ResNet-based classifier, achieving over 85% accuracy with minimal training data. This project delivered the first proof of concept for automated rock analysis at SLB. The image labeling tool developed during this project is available on my GitHub.
[GitHub Project Link]

SpecPT

Real-Time Transient Classification

Developed CNN-based classifiers to identify transient events (e.g., supernovae) from real-time photometric data during a research visit to Swinburne University. This automation reduced human inspection volume by over 95%, significantly improving the response rate to time-critical events in astronomy.

SpecPT

Detecting the 21cm Reionization Signal

Developed an artificial neural network model to distinguish faint 21cm Epoch of Reionization signals from foreground contamination using simulations. Achieved 92% accuracy and demonstrated the potential of ML for cosmological signal extraction, advancing efforts in observational cosmology.
[Paper Link]

Selected Publications

Citation Metrics

Total Citations318
h-index5
i10-index4

Some Invited Talks & Conference Presentations

SpecPT: Spectroscopy Pre-trained Transformer model for Galaxy Spectra

AI/ML Applications in Astronomy & Astrophysics (Jan 2025)

Applications of Machine Learning in Astronomical Research: A Brief Overview

Physics Colloquium Talk at SUNY Geneseo (2024)

AstroLLMs: AstroLLaMa Abstracts

.Astronomy 12: Flatiron Institute, New York (2023)

In the Local News! Talking about our Citizen Science project- Redshift Wrangler

WROC (2023)

Towards Automating the Measurements of Spectroscopic Redshifts and Emission Line Measurements

COSMOS Meeting Paris (2022)

Machine Learning in X-Ray Astronomy: Classifying Black Holes and Neutron Stars in Binary Systems

PyData London (2018)

Resume

A concise 1-page summary highlighting my academic and professional milestones.

CV

A detailed look into my research, publications, work experience, and academic journey.