The Groundbreaking Discovery of a Star's Silent Demise

Astronomers have long theorized that not all massive stars end their lives in spectacular supernova explosions. Instead, some may undergo a 'direct collapse,' where their cores implode straight into black holes without the dramatic fireworks. Recent research provides the clearest evidence yet of this elusive process, led by Indian-origin astronomer Kishalay De. The event, captured in archival data from NASA's NEOWISE space telescope, involves a massive star in the Andromeda galaxy that simply vanished after years of infrared brightening, leaving behind a dusty remnant indicative of a failed supernova.

This discovery, detailed in a paper published in the journal Science, challenges traditional models of stellar evolution and black hole formation. It highlights how subtle infrared signals can reveal cosmic events that optical telescopes might miss entirely.

Kishalay De: From IISc Bangalore to Global Astronomy Leader

Kishalay De, born and raised in Kolkata, India, embodies the success story of India's robust higher education system in nurturing top-tier scientific talent. He earned his undergraduate degree in physics from the prestigious Indian Institute of Science (IISc) in Bangalore in 2016, where he developed a passion for astrophysics. De then pursued a PhD at the California Institute of Technology (Caltech), graduating in 2021, before joining Columbia University as an Assistant Professor of Astronomy.

Today, as a faculty member at Columbia and an associate research scientist at the Simons Foundation's Flatiron Institute, De leads cutting-edge research on transient astronomical events. His work on the disappearing star M31-2014-DS1 showcases how foundational training at Indian institutions like IISc propels researchers to international prominence. For aspiring astronomers in India, De's trajectory underscores the value of strong physics programs and research opportunities available at premier universities.

Understanding the Star M31-2014-DS1 and Its Demise

The star in question, designated M31-2014-DS1, was located in the Andromeda galaxy (M31), our nearest large galactic neighbor, about 2.5 million light-years away. Initially estimated at around 13 times the mass of the Sun, it had shed much of its outer envelope through powerful stellar winds, reducing its mass to approximately five solar masses by the end of its life. As a hydrogen-depleted supergiant, it was primed for a dramatic finale—but instead of exploding, it faded quietly.

The process unfolded over years: from 2014 onward, NEOWISE detected steady infrared brightening, likely from dust formed as the star ejected material. Then, beginning around 2017, the light dimmed dramatically and the star effectively disappeared from view, swallowed by the black hole formed from its core collapse. Ground-based follow-up with the Keck Observatory's NIRES spectrograph confirmed the absence across wavelengths, ruling out alternatives like a dusty supernova or variable star behavior.

The Science of Direct Collapse Black Hole Formation

Stellar black holes form when massive stars exhaust their nuclear fuel. Conventionally, stars above eight solar masses are expected to undergo core collapse, triggering a supernova that blasts away outer layers while the core becomes a black hole or neutron star. However, for stars in the 20-40 solar mass range—or those that have lost mass via winds—the outer layers may fall inward too quickly, failing to rebound as a shock wave.

• Step 1: Core runs out of fuel, iron accumulates, unable to support against gravity.
• Step 2: Core collapses to neutron-degenerate matter, but if mass exceeds Tolman-Oppenheimer-Volkoff limit (~2-3 solar masses), it implodes fully into a black hole.
• Step 3: No successful shock forms; outer envelope accretes quietly, producing faint infrared from dust-obscured infall.
• Step 4: Star dims over months to years, leaving mid-infrared excess as evidence.

This 'failed supernova' scenario, theorized since the 1970s, explains why some black holes lack supernova remnants. De's observation is the strongest empirical support yet, suggesting these events are more common but harder to detect without infrared surveys.

Key Technologies and Observations Enabling the Breakthrough

NASA's NEOWISE mission, launched in 2011 as WISE and repurposed for time-domain infrared surveys, was pivotal. Scanning the entire sky every few months, it captured the multi-year light curve of M31-2014-DS1. De's team sifted through vast archives—the largest survey of infrared variables in nearby galaxies—identifying this outlier amid millions of sources.

Complementing space data, the W.M. Keck Observatory on Mauna Kea provided high-resolution near-infrared spectra, confirming the source's disappearance and faint dust signature. Such synergies between space and ground telescopes are crucial for transient astronomy. For more on advanced observational techniques, explore the full paper in Science.

Indian researchers increasingly contribute to such global efforts through facilities like the Giant Metrewave Radio Telescope (GMRT) and upcoming Square Kilometre Array (SKA) involvement.

Implications for Astrophysics and Black Hole Populations

This discovery reshapes models of stellar evolution. Prior estimates suggested direct collapses contribute ~10-30% of stellar black holes; M31-2014-DS1 implies they may dominate for intermediate-mass stars. It also informs gravitational wave detections: LIGO/Virgo mergers often lack electromagnetic counterparts, possibly due to quiet progenitors.

Galaxy-wide, failed supernovae retain more metals, affecting chemical enrichment. For black hole demographics, it predicts a population of ~5-10 solar mass holes from direct collapse, bridging the 'pair-instability gap.' Future surveys like Roman Space Telescope will hunt more candidates.

India's Growing Role in Astronomy and Black Hole Research

India boasts world-class institutions driving astronomy research. The Indian Institute of Astrophysics (IIA) in Bengaluru studies black hole accretion and jets. Inter-University Centre for Astronomy and Astrophysics (IUCAA) in Pune excels in gravitational waves and multimessenger astronomy, collaborating with LIGO-India.

National Centre for Radio Astrophysics (NCRA) operates GMRT, pivotal for radio black hole imaging like M87*. Recent highlights include AstroSat's black hole QPO detections and studies on supermassive black hole feedback suppressing star formation. Kishalay De's IISc roots exemplify how these hubs feed global talent pipelines.

Astronomy Programs in Indian Higher Education Institutions

India's universities offer robust programs for astronomy aspirants. IISc Bangalore's Department of Physics and Astronomy provides integrated MSc-PhD tracks with specializations in astrophysics, emphasizing computational modeling and observations. IIA offers graduate programs affiliated with universities, focusing on stellar evolution and cosmology.

IUCAA's National Centre for Theoretical Sciences runs summer schools and PhD programs. Indian Institute of Space Science and Technology (IIST) integrates space science with engineering. Osmania University and IIT Indore also feature MSc Astronomy and astrophysics courses. These programs equip students with skills in data analysis, vital for missions like Aditya-L1 and future black hole studies.

• IISc: BS-MS, PhD in Astrophysics
• IIA: Integrated MSc-PhD
• IUCAA: Joint PhD with Pune University
• IIST: BTech + MTech Space Science

Check research assistant jobs at these institutions for entry points.

Career Pathways and Opportunities in Indian Astrophysics

Pursuing a career in astrophysics from India opens doors to academia, space agencies, and industry. Post-MSc/PhD, roles include postdocs at IIA/NCRA, faculty positions at IITs/IISc, or ISRO scientist posts. Salaries start at ₹8-12 lakhs for juniors, rising to ₹20+ lakhs for professors.

Skills in Python, machine learning for data pipelines, and infrared analysis are in demand. International collaborations via LIGO-India and SKA enhance prospects. De's path—from IISc to Columbia—shows mobility; many return as faculty. Explore tips for academic CVs and professor jobs in higher ed.

Future Outlook: Next Steps in Direct Collapse Research

Future infrared missions like SPHEREx and Roman will survey deeper, uncovering more failed supernovae. Ground-based Extremely Large Telescopes will spectroscopically confirm candidates. In India, uGMRT upgrades and AstroSat-2 promise local contributions to transient hunts.

This event predicts ~1 such occurrence per decade in nearby galaxies, detectable with vigilant monitoring. It paves the way for linking electromagnetic transients to gravitational waves, revolutionizing multimessenger astronomy.

For those inspired, visit India higher ed jobs and postdoc advice.

Photo by Ankit Manoharan on Unsplash

Why This Matters for Higher Education and Research in India

De's achievement spotlights India's potential as a global astronomy hub. With Union Budget 2026 allocating ₹55,727 crore to higher ed, including research boosts, institutions are expanding AI and computational astrophysics.Related budget insights. Students gain from scholarships, international exchanges, and facilities like 30m class telescopes planned.

Encouraging interdisciplinary training prepares the next De. Engage with Rate My Professor, browse higher ed jobs, and university jobs to start your journey. Share thoughts in comments below.