Story perspectives

Interstellar comet 3I/ATLAS shows double-solar isotopes, formed around ancient star

7/14/2026

Summary

Story summary

Astronomers observed interstellar comet 3I/ATLAS as it passed near Earth on October 30 2025.
Cyrielle Opitom led a team that used the Very Large Telescope (VLT)’s Ultraviolet and Visual Echelle Spectrograph to record spectra.
The VLT spectra showed nitrogen-14/ nitrogen-15 and carbon-12/ carbon-13 ratios twice Solar System comet values.
Combined VLT and James Webb Space Telescope suggest the comet formed in outer region of an old, low-metallicity star’s disk before the Sun.

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Story summary

Astronomers observed interstellar comet 3I/ATLAS as it passed near Earth on October 30 2025.
Cyrielle Opitom led a team that used the Very Large Telescope (VLT)’s Ultraviolet and Visual Echelle Spectrograph to record spectra.
The VLT spectra showed nitrogen-14/ nitrogen-15 and carbon-12/ carbon-13 ratios twice Solar System comet values.
Combined VLT and James Webb Space Telescope suggest the comet formed in outer region of an old, low-metallicity star’s disk before the Sun.