Revolutionary Discovery in Cosmic Dawn

In an astounding breakthrough, astronomers have uncovered dust-covered supermassive black holes dating back to the early universe—just under 1 billion years after the Big Bang. This groundbreaking finding shines a light on celestial objects that had eluded detection until now.

A Collaborative Effort

The international research team, featuring experts from Ehime University and the National Astronomical Observatory of Japan, initially flagged candidate galaxies using the Subaru Telescope. They later confirmed these galaxies harbored supermassive black holes that shimmer as quasars while consuming surrounding matter, utilizing the powerful capabilities of the James Webb Space Telescope (JWST).

Twice as Common as Previously Thought

This pivotal discovery reveals that bright quasars—once thought to be rare—are actually at least twice as prevalent in the early universe. The study has been published in *The Astrophysical Journal*, emphasizing its significance in our understanding of cosmic evolution.

Black Holes: Nature's Mysteries

In today's universe, nearly every galaxy houses supermassive black holes at their core, with masses exceeding millions of suns. Although most remain inactive, when they gather surrounding matter, they transform into powerful quasars, emitting intense radiation that influences the host galaxy's growth and evolution.

The Mystery of Formation

Despite being crucial to cosmic evolution, the origins of these supermassive black holes remain shrouded in mystery. Many are discovered as far back as 1 billion years after the Big Bang, signaling their formation must have happened even earlier, leading astronomers to explore the so-called "Cosmic Dawn".

Dust-Dimmed Quasars

In their pursuit, researchers recognized that previous methods of detection, focusing primarily on ultraviolet light, might miss numerous quasars hidden by cosmic dust. The research team, operating with the Subaru Telescope, began to suspect the existence of these obscured quasars for over a decade.

A Game-Changer: James Webb Space Telescope

With the JWST's launch, a new era of astronomical observation began. For the first time, astronomers could detect visible light from these dust-enshrouded galaxies in infrared wavelengths, allowing them to penetrate the cosmic veil that previously obstructed their view.

Confirming the Existence of Dust-Covered Quasars

Using the NIRSpec spectrograph aboard the JWST, the team implemented observations between July 2023 and October 2024, focusing on 11 luminous galaxies. Remarkably, seven of these galaxies displayed broad emission lines—a definitive sign of quasars—confirming the existence of these rare, dust-shrouded entities.

Shedding Light on the Universe’s Secrets

The spectra analysis revealed these quasars emit energy equivalent to trillions of suns, powered by black holes with masses of several billion suns. With dust absorbing about 70% of visible light and 99.9% of ultraviolet light from these quasars, the study clarifies why they had previously gone unnoticed.

A Paradigm Shift in Cosmic Understanding

Dr. Yoshiki Matsuoka from Ehime University, leading this trailblazing study, stated, "This discovery was only made possible through the synergistic use of both the Subaru Telescope and JWST, demonstrating the effectiveness of our strategy—‘Discover with Subaru, explore with James Webb.’”

What's Next?

Looking ahead, the research team intends to investigate whether these obscured quasars exhibit fundamental differences from conventional ones. Future studies will also leverage the ALMA telescope for detailed analyses of the galaxies hosting these intriguing black holes.