3I/ATLAS: New Interstellar Object Exhibiting Cometary Properties
Astronomers have discovered a new mysterious object that arrived from beyond our Solar System. It has become the third recorded interstellar visitor in history after the famous 'Oumuamua and Comet Borisov.
What Happened?
On July 1, the ATLAS survey telescope (Asteroid Terrestrial-impact Last Alert System) in Río Hurtado, Chile, first reported observations of a comet arriving from interstellar space. Coming from the direction of the Sagittarius constellation, the interstellar comet received the official designation 3I/ATLAS. It's currently located about 420 million miles (670 million kilometers) away. Its trajectory indicates it doesn't belong to our Solar System and is a "cosmic wanderer" arriving from the depths of interstellar space.
Key Evidence: Unusual Orbit
The key factor indicating the object's extrasolar origin is its orbit.
Hyperbolic trajectory: Unlike planets and asteroids in our system that orbit along elliptical paths, 3I/ATLAS follows a hyperbolic trajectory.
High eccentricity: The object's eccentricity (orbital elongation measure) is about 6.15 ± 0.17. Any object with eccentricity greater than 1 isn't gravitationally bound to the Sun. This means it will make only one flyby past our star before leaving the Solar System forever.
The Cosmic Wanderer's Path
Arrival direction: Moving across the sky along the border of the Serpens and Sagittarius constellations, near the galactic plane.
Solar approach: Closest approach to the Sun (perihelion) is expected on October 30, 2025, passing just inside Mars' orbit.
What's Next?
Astronomers worldwide are studying the size and physical properties of this interstellar comet. 3I/ATLAS should remain visible to ground-based telescopes until September, after which it will pass too close to the Sun for observation. It's expected to reappear on the other side of the Sun in early December, allowing observations to resume.
Properties
Its width is estimated at up to 12 miles (20 km), with a speed relative to the Sun of about 134,000 mph (60 km/s). It poses no danger to Earth, approaching no closer than 150 million miles (240 million km) - equivalent to over 1.5 astronomical units (AU, the Earth-Sun distance).
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