3I/ATLAS Explained, Forensic Fingerprints & Alzheimer’s Breakthrough (EP. 18)

Hosted by Lester Nare and Krishna Choudhary, this episode spans astrophysics, forensic chemistry, and neuroimmunology. We begin with a deep dive into 3I/ATLAS, only the third confirmed interstellar object to ever pass through our solar system — larger and stranger than ‘Oumuamua and Borisov, with new imagery released as NASA reopened operations. Then we break down a true-crime forensic breakthrough from Maynooth University that reveals how to recover fingerprints from fired bullet casings — a technique that could radically accelerate criminal investigations. And we close with a Max Planck Institute discovery identifying a regulatory microglial state in the brain that may finally clarify why Alzheimer’s develops — and how immune dysfunction, not just plaques, drives the disease.

Summary
• The third interstellar visitor — 3I/ATLAS joins ‘Oumuamua and Borisov as only the third object ever observed entering the solar system from interstellar space, with new NASA imagery revealing structure, trajectory, and compositional clues.

• A forensic chemistry breakthrough — researchers at Maynooth University develop a technique to retrieve latent fingerprints from fired shell casings, combining heat-stable organic residues with spectroscopic imaging.

• A new model of Alzheimer’s — Max Planck Institute scientists uncover a microglial “regulatory” state (a T-reg–like analogue) activated through CD28-dependent pathways, reshaping how the field thinks about plaques, neuroinflammation, and therapeutic targets.

Show Notes
• 3I/ATLAS — Interstellar Object Updates (NASA / JPL) (science.nasa.gov/solar-system/comets/3i-atlas)
• Forensic Chemistry: Fingerprints on Fired Casings (Maynooth University) (doi.org/10.1016/j.forc.2025.100663)
• Alzheimer’s Microglia Study — Max Planck Institute / Univ. of Cologne (nature.com/articles/s41586-025-09662-z)