Oldest Interstellar Comet 3I/ATLAS Discovered by ATLAS

Oldest Interstellar Comet 3I/ATLAS Discovered by ATLAS

Why in the News?

A new interstellar comet, named 3I/ATLAS, has been discovered by scientists using Chile’s ATLAS telescope. Likely older than our solar system, it presents a unique opportunity to study primordial material from other star systems and early galactic formation.

Scientific Discovery and Key Features:

• 3I/ATLAS is the third known interstellar object, after 1I/’Oumuamua (2017) and 2I/Borisov (2019).
• It was first tracked on June 14, 2024, and confirmed on July 1, via the ATLAS telescope in Chile.
• The comet is travelling at 57–68 km/s and follows a hyperbolic orbit, confirming it’s not bound to the Sun.
• It will pass closest to the Sun around October 29–30, 2025, at 210 million km, and to Earth at 270 million km.
• It will exit the solar system permanently after this passage.

Astrophysical Significance and Future Prospects

• 3I/ATLAS may have originated in the Milky Way’s thin or thick disk, possibly 3+ billion years old.
• Studying it provides insights into the chemical composition of other star systems and the early galaxy.
• Multiple global observatories are tracking its composition, trajectory, and activity before it fades.
• The comet may be visible to amateur astronomers using small telescopes in late 2025 or early 2026.
• This rare event strengthens global interest in interstellar astronomy and space science research.

About Interstellar Objects and Comets:

• Interstellar objects originate outside our solar system, carrying primordial materials from ancient star systems.
• Comets typically contain ice, dust, and organic compounds, forming a coma and tail as they approach stars.
• The reddish hue and spectral slope of 3I/ATLAS suggest the presence of complex organics or water ice.
• The nucleus size is estimated at 10–30 km, larger than earlier interstellar objects.
• Such discoveries help understand planet formation, stellar evolution, and galactic dynamics.