Astronomers utilizing the Gemini North telescope at NSF’s International Gemini Observatory have observed the interstellar comet 3i/Atlas as it passes through our cosmic neighborhood.
This image from the Gemini North Telescope Multi-Object Spectrometer (GMOS-N) showcases the interstellar comet 3i/Atlas. Image credits: International Gemini Observatory/Noirlab/NSF/Aura/K. Meech, Ifa&U. Hawaii / Jen Miller & Mahdi Zamani, Noirlab.
Interstellar objects are those that emerge from and traverse beyond our solar system.
Ranging from several meters to a few kilometers in size, these cosmic fragments are remnants from the formation of the host star’s planetary system.
As they orbit their stars, interactions with the gravitational pull of nearby planets and stars can eject them into interstellar space, allowing them to traverse other solar systems.
Studying interstellar visitors provides critical insights into distant star systems.
They carry valuable information about chemical elements, including their formation timelines and locations, offering scientists glimpses into the formation of planetary systems throughout the history of the Milky Way galaxy.
3i/Atlas marks the third interstellar object discovered, following 1i/Oumuamua in 2017 and 2i/Borisov in 2019.
Astronomers suspect that numerous interstellar objects might regularly pass through our solar system, but capturing them is challenging as they are only visible when telescopes are oriented correctly at the right time.
Multiple teams worldwide utilize various telescopes to monitor 3i/Atlas during its brief visitation, enabling them to collectively assess its key properties.
While many aspects remain unknown, 3i/Atlas is already recognized as distinct in comparison to 1i/Oumuamua and 2i/Borisov.
Previous observations suggest that 3i/Atlas could have a diameter of up to 20 km (12 miles).
New comets typically exhibit highly eccentric orbits, which define how much the object’s path deviates from a perfect circle.
An eccentricity of 0 indicates a circular orbit, while 0.999 signifies a highly elongated ellipse.
Objects with an eccentricity greater than 1 follow paths that do not loop around the Sun and come from, then return to, interstellar space.
The eccentricity of 3i/Atlas is recorded at 6.2, classifying it as a highly hyperbolic interstellar object.
In contrast, “Oumuamua’s” eccentricity was around 1.2, and Borisov’s was about 3.6.
As of now, 3i/Atlas resides in Jupiter’s orbit, approximately 465 million km (290 million miles) from Earth and 600 million km (370 million miles) from the Sun.
On December 19, 2025, it will come within roughly 270 million km (170 million miles) of Earth, posing no threat to our planet.
The closest approach to the Sun will occur around October 30, 2025, at a distance of 210 million km (130 million miles).
During this close approach, it is expected to travel at about 25,000 km (15,500 miles) per hour.
The latest image of 3i/Atlas was obtained using the Gemini North Telescope Multi-Object Spectrometer (GMOS-N).
“The sensitivity and scheduling precision of the International Gemini Observatory played a critical role in observing this interstellar wanderer,” remarked Martin Still, NSF Program Director at the International Gemini Observatory.
“We eagerly anticipate the wealth of new data and insights as this object warms in sunlight before continuing its cold, dark journey through interstellar space.”
Source: www.sci.news
