Silicone Imprint of Ancient Stars express

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The galaxy NGC 1277 is like an old book that no one has opened for billions of years. It formed quickly at the dawn of the Universe and has barely changed since — no collisions with neighbors, no new layers added. Astronomers call such systems 'relics': they preserve the chemical composition of the first stars, much like amber preserves prehistoric insects.

Using deep infrared spectroscopy, scientists peered into the galaxy's chemical record. They were in for a surprise: silicon absorption lines turned out to be unusually strong. The silicon-to-iron ratio exceeded the solar value by dozens of times, and crucially, silicon was far more abundant than magnesium. Current stellar population models and typical core-collapse supernovae cannot produce such an excess.

Such supernovae, called pair-instability, could only occur in an environment nearly devoid of heavy elements: that is, among the very first generation of stars. In massive galaxies that grew slowly, this signal has long been diluted by subsequent generations. But NGC 1277 formed rapidly and then froze, preserving this rare chemical autograph. This discovery opens a window into the era when the Universe was just learning to create complex atoms, and hints at what its first stellar giants were like.