Comet 3I/Atlas passes through perihelion and reveals 7 billion-year-old secrets at 61 km/s
Astronomers confirm that the interstellar comet 3I/Atlas, the third object of origin outside the Solar System, reached perihelion last week. The celestial body, estimated to be 5 to 7 billion years old, maintained a distance of 204 million kilometers from the Sun. Emerson Roberto Perez, astronomer at Urânia Planetário, explains the unusual behavior in an exclusive interview.
The speed of 61 km/s, a record for comets, intrigues scientists. The object formed near the center of the Milky Way and offers insights into distant planetary systems.
- Speed: 61 km/s, higher than other interstellar comets.
- Age: 5 to 7 billion years, predating the Solar System.
- Distance to the Sun: 204 million km at perihelion.
Distant origin of comet 3I/Atlas
Comet 3I/Atlas originated in a region close to the galactic center.
Its dense composition differs from local comets.
Trajectory and record speed
The comet travels at 61 km/s through the Solar System. This speed surpasses recordsprevious reports of interstellar objects. Astronomers have been monitoring the path since the initial detection.
The passage through perihelion occurred on October 27th. The object maintains a hyperbolic orbit, confirming an external origin.
Chemical composition revealed
The dense structure of 3I/Atlas indicates formation in an environment rich in heavy metals. Spectroscopic analyzes detect rare organic compounds. These elements suggest extreme conditions in the galactic cradle.
Compared to 1I/’Oumuamua and 2I/Borisov, 3I/Atlas has a higher albedo.
Meeting with Clipper probe in December
The Clipper probe will cross the comet’s tail on December 15. This interaction will collect interstellar particles for the first time. Mission instruments will record data on dust and gases.
The analysis will take place in real time during the trajectory to Jupiter. Preliminary results expected in January 2026.
Maximum approach to Earth
The point of greatest proximity occurs on December 19th. Distance: 1.8 astronomical units, or 270 million km.
Observation requires professional telescopes. Binoculars do not capture the object due to the weak magnitude.
Recommended Telescopic Notes
Astronomers predict peak brightness in December. Amateur telescopes with a diameter above 20 cm detect the comet.
- Ideal location: Southern Hemisphere, away from light pollution.
- Time: Early morning, between 2am and 5am.
- Useful apps: Stellarium or SkySafari for tracking.
Historical data on interstellar comets
3I/Atlas is part of the list of extrasolar visitors. ‘Oumuamua arrived in 2017 without a visible coma. Borisov, in 2019, showed a gaseous tail.
The new comet has a compact coma and a 1 km nucleus. Escape velocity confirms trajectory not linked to the Sun.
Clipper mission and sample collection
The probe, launched in October, is heading to Europe. Encounter with comet’s tail adds scientific objective.
Particles collected via impactors will measure mass and velocity. Data will enrich studies on star formation.
Preparations for global preview
Observatories in Chile and Australia activate cameras. Networks like Slooh offer remote access.
Scientific community schedules webinars in November. Enthusiasts prepare astrophotography sessions.
Chronology of 3I/Atlas detection
Detection occurred on July 28, 2025 by ATLAS. Interstellar confirmation in August via ESO.
Perihelion: October 27th. Exit from the Solar System scheduled for February 2026.
Contributions to astrophysics
The comet provides samples of primordial matter. Studies reveal chemical evolution in the Milky Way.
Clipper data will validate interstellar migration models. Publications in magazines such as Nature awaited.
