NASA's Webb and Hubble telescopes reveal Terzan 5 isn't a globular cluster but a fossilized fragment of the Milky Way's formation—rewriting galactic history. This discovery reshapes how we understand our galaxy's violent origins.

KEY TAKEAWAY Terzan 5 contains two distinct populations of stars with a 7-billion-year age gap—impossible for a true globular cluster

KEY TAKEAWAY Its iron content varies by 300% between stars, proving it formed from multiple galactic fragments

KEY TAKEAWAY Webb's infrared vision pierced dust that obscured Hubble's view, enabling the breakthrough

KEY TAKEAWAY This changes how we search for other "fossil" structures hiding in plain sight

KEY FACT Terzan 5's stars have iron abundances ranging from 0.2 to 0.6 times the Sun's—a spread unheard of in true globular clusters.

Webb and Hubble Uncover a Fossil From the Milky Way's Birth

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