The new Interstellate 3i/Atlas object discovered: high speed, hyperbolic orbit, possible comet or asteroid. It will pass near Mars and the Earth.
Wednesday morning 2 July 2025, the world of astronomy was shaken by a discovery Of large relevance: a mysterious interstellar object, now called 3i/Atlasours is crossing ours at great speed solar system.
The object, initially designated A11PL3Zwas identified for the first time on 1 July 2025 by the system Atlas (Asteroid Terrestrial-Impact Last Alert System) at Rio Hurtado, in Chile. Already the next day it was detected by the remote telescope Deep Random Survey.
Origins and retrospective identification
Retrospective observations (pre -core) conducted by Atlas, from Zwicky Transient Facility (Palomar) and other telescopes indicate that the object was visible since June 14th.
With a apparent magnitude of about +183i/Atlas appears weak, but stands gradually increasing its brightness. It is worth remembering that the magnitude measures the apparent brightness of a celestial object; The lower the value, the brighter the object is.
Orbit and trajectory: an interstellar visitor
There its orbital eccentricity estimated between 6 and 6.1 (therefore hyperbolic) is the higher ever recorded for an interstellar object.
For reference:
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eccentricity 0 = circular orbit
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between 0 and 1 = elliptical orbit
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greater than 1 = Open orbit (hyperbolic or parabolic)
THE’retrograde inclination Of 175 ยฐ Along the galactic plan it suggests an origin outside our sun system. There speed current is estimated between 60 and 68 km/s (beyond 200,000 km/h).
Comet or asteroid? The uncertain nature of 3i/Atlas
Initially classified as asteroidthe detection of a Alone Cometorio and a short tail of about 3 “ opened the possibility that it is a comet.
At the moment, however, its nature remains uncertain: it could be a rocky asteroid of about 20 km in diameter or one icy comet with marginal activity.
Key dates: close observations
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3 October 2025 – approach to Mars (about 0.195 UA, equal to approximately 29.2 million km), potentially observable by the Martian probes, in particular by Mars Reconnaissance Orbiter
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29 October 2025 – Perihelionpoint closest to the sun (1.35 UA, 20 mlions of km)
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December 17, 2025 – Maximum approach to the earthat about 2.4 UA or 359 million km.
No mission: too high speed
With a trajectory so hyperbolic and one so high speed Any attempt to send a probe to intercept 3i/Atlas is today impracticable.
The most important observations will come from space telescopes such as the James Webb Space TelescopeThe Vera C. Rubin Observatory (which has already identified over 2,000 new asteroids in the tests) and of course the Martian probes.
Because 3i/Atlas is so special
3i/Atlas is the Third interstellar object confirmed in history, later 1i/Oumuamuadiscovered in 2017, e 2i/Borisovobserved in 2019.
It is estimated that in our solar system There are constantly at least 10,000 interstellar objects with a diameter of over 100 meters. The study of these visitors offers Precious information about other star systems: if they were detected organic compounds or amino acidsthis could suggest one Cosmic diffusion of the elements behind life.
