In the summer of 2022, our views of the distant Universe — and our story of how galaxies formed and grew up — changed forever as the James

JWST fully solves the mystery of “Little Red Dots”

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2025-01-15 17:00:17

In the summer of 2022, our views of the distant Universe — and our story of how galaxies formed and grew up — changed forever as the James Webb Space Telescope (JWST) began science operations. With superior light-gathering power, it could detect fainter objects than ever before. With superior resolution, it could differentiate single-source objects from extended or multi-source objects better than ever before. And with its infrared-specialized capabilities, it could detect more distant, high-redshift objects than ever before. With the incredible technology aboard JWST, we were poised to learn about the earliest stages of cosmic history as far as stars, galaxies, and supermassive black holes were concerned.

Unexpectedly, a new class of object — Little Red Dots (LRDs) — showed up in great abundance in the data. These LRDs didn’t line up with our expectations at all: they were very bright, which suggested tremendous stellar masses, but were so great in number, at such early times, that the complete picture didn’t add up. Now, at the start of 2025, we’ve finally solved the puzzle, with active supermassive black holes playing an all-important role in explaining the Universe.

In most galaxies that we see and measure, there are only two major reasons behind why a galaxy would be intrinsically red in color when we observe it.