Scientists are buzzing with excitement over the discovery of a rare interstellar visitor racing through our solar system at a mind-boggling speed. The object, named 3I/ATLAS, is only the third confirmed interstellar object ever detected in our solar system and appears to be a comet based on its glowing coma and short tail. How will scientists benefit from studying material from another star?
A Rare Cosmic Visitor
Astronomers have confirmed the discovery of an extraordinary interstellar object speeding through our solar system, marking only the third such visitor ever detected. The object, officially named 3I/ATLAS, was first spotted by NASA’s Asteroid Terrestrial-impact Last Alert System (ATLAS) in Chile, and subsequent observations have confirmed its interstellar origin.
This cosmic traveler is racing through space at approximately 130,000 miles per hour, which Harvard’s Avi Loeb described as a “thousand times over the speed limit on a highway.” The comet’s high velocity and trajectory are key indicators of its interstellar nature, as objects originating within our solar system typically move at much slower speeds.
The European Space Agency (ESA) announced, a few days ago, the discovery of a rare interstellar object: the comet 3I/ATLAS, the third object of this type ever identified, after 1I/ʻOumuamua (2017) and 2I/Borisov (2019).
Detected on July 1, 2025 by the ATLAS telescope in Río… pic.twitter.com/OhRK6Ap7Kq— Nereide (@Nereide) July 6, 2025
Characteristics and Current Position
3I/ATLAS is currently located approximately 420 million miles from Earth, between the asteroid belt and Jupiter. The object appears to be a comet rather than an asteroid, evidenced by its developing coma (a cloud of gas and dust) and short tail that forms as ice on its surface sublimates in the heat of the sun.
While its exact size remains uncertain, preliminary estimates suggest it could span approximately 25 miles across if it’s a solid body. However, determining its precise dimensions is challenging due to the glowing coma surrounding it, which makes the object appear larger than its actual solid nucleus.
There's a new interstellar comet in the neighborhood!
Known as 3I/ATLAS, this comet poses no threat to Earth – but it does provide a rare opportunity to study an object that originated outside of our solar system: https://t.co/7ihCiHi91t pic.twitter.com/2XT3NRyCOz
— NASA JPL (@NASAJPL) July 2, 2025
Scientific Opportunity and Timeline
This interstellar visitor provides a rare opportunity for astronomers to study material from beyond our solar system. Unlike the previous interstellar objects ‘Oumuamua (2017) and 21/Borisov (2019), 3I/ATLAS will be observable for an extended period, giving scientists more time to conduct detailed observations.
The comet is expected to make its closest approach to the sun around October 30, passing at a distance of about 130 million miles. Astronomers plan to study the object intensively until September, after which it will pass too close to the sun for observation before reappearing in early December.
Paul Chodas of NASA’s Center for Near Earth Object Studies emphasized the certainty of the object’s interstellar nature, stating “There’s no uncertainty.” The object’s trajectory suggests it originated from the direction of the constellation Sagittarius, which aligns with the center of our galaxy, potentially offering insights into the composition of objects from the deep galactic core.
Multiple telescopes around the world, including the Zwicky Transient Facility, are now tracking 3I/ATLAS to gather data about its composition, behavior, and characteristics. The extended observation window will allow scientists to conduct more comprehensive studies than were possible with previous interstellar visitors, potentially revealing new information about the materials and conditions in distant star systems.