Two Monster Black Holes Defy Cosmic Clock Just 900 Million Years In

Why can't theory explain it?

The first billion years of cosmic time were a period of furious assembly. Dark matter halos collapsed, galaxies ignited their first stars, and the earliest supermassive black holes formed at galactic centers. As galaxies collided and merged, gas and stars fed those black holes, and a fraction of that material converted into energy — producing the extreme brightness that defines a quasar.

Here's the puzzle. Galaxy mergers are common, so astronomers expect plenty of closely separated quasar pairs. But they're hard to actually find, for three reasons:

• A supermassive black hole's quasar phase is relatively short.
• These objects are extremely distant, faint and hard to detect from the ground.
• At small separations, the two members of a pair blur together and resist being resolved.

Nāpōwawāʻenakaulua is only the third known quasar pair from cosmic dawn. But it's not just rare — it's so early that no model comfortably accounts for it.

"There is no definitive theoretical explanation for how a single one of these giant quasars exists so early in the age of our universe, much less two," Onorato said.

How did the team spot it?

The find came out of the Aether survey, a JWST program led by Emanuele Paolo Farina, associate scientist at NSF NOIRLab/Gemini, which is building a census of early-universe objects. Using JWST's Near-Infrared Spectrograph Integral Field Unit, the survey gathered a sample of 200 quasars — 43% of all known quasars at this stage of cosmic history. During visual inspections of that data, the team noticed that quasar J1602+4228A had a companion.

Follow-up observations with Gemini North, the telescope on the dormant volcano Maunakea in Hawai'i, split the pair into two distinct objects using the Gemini Near-Infrared Spectrograph (GNIRS). That shouldn't have been easy: J1602+4228B is so faint, and the two so close, that a ground-based detection should have been nearly impossible.

The weather cooperated. "The sky over Maunakea was so clean and sharp that we managed to collect the data in only two nights," Onorato said. Additional observations with the Gemini Multi-Object Spectrograph (GMOS) further pinned down the pair's properties.

What does the pair tell us about the early universe?

The full origin story remains a mystery, and these are preliminary interpretations from a single object. But the team proposes the quasar pair may mark an extreme peak in the early universe's matter density — a region dense enough that galactic interactions simultaneously fueled star formation and rapid black hole growth.

"Nāpōwawāʻenakaulua is a really unique environment," Onorato said. "It's a laboratory for astronomers to study how the very first massive galaxies and their central black holes assembled together through direct galaxy interactions during these early times."

The paper is Silvia Onorato et al., "Nāpōwawā'enakaulua: A Close Quasar Pair at Cosmic Dawn in the Aether Survey," The Astrophysical Journal Letters (2026), DOI: 10.3847/2041-8213/aeb11f.