Newly spotted comet is third interstellar object

4/7/2025 6:16

Astronomers are tracking

a newly spotted comet hailing from parts unknown, only the third

time such an interstellar object has been observed visiting our

solar system.



According to U.S. space agency NASA, the interloper - named

3I/ATLAS - was first spotted on Tuesday by an Asteroid

Terrestrial-impact Last Alert System, or ATLAS, telescope

located in Rio Hurtado, Chile. Astronomers said its unusual

trajectory indicated it had ventured from beyond our solar

system.



Journeying at a speed of around 37 miles (60 km) per second

from the direction of the center of the Milky Way galaxy,

3I/ATLAS is presently located about 420 million miles (670

million kilometers) from Earth.



"Beyond that we do not know very much, and there are many

efforts underway to observe this object with larger telescopes

to determine composition," University of Hawaii astronomer Larry

Denneau, co-principal investigator for ATLAS, said on Thursday.



The only other such interstellar visitors previously

observed by astronomers were objects called 1I/'Oumuamua

(pronounced oh-MOO-uh-MOO-uh), detected in 2017, and 2I/Borisov,

discovered in 2019.



"The comet has some similarities to 2I/Borisov in that it

appears to be an icy comet, but it is much larger, possibly 10

km (6.2 miles) in diameter," Denneau said.



"It currently has a faint coma," Denneau added, referring to

the cloud of gas and dust surrounding a comet's nucleus, "but

the coma and tail may increase dramatically as the object comes

closer to the sun. Its closest approach to the sun will be later

this year, when it will come inside the orbit of Mars. We don't

know what will happen, so that's exciting."



Astronomers said the comet poses no threat to Earth and will

never come closer than 150 million miles (240 million km) away,

equivalent to more than 1-1/2 times the distance between Earth

and the sun. It is currently located about 416 million miles

(670 million km) from the sun and will reach its closest

approach to the sun around October 30, when it will be about 130

million miles (210 million km) away from our star.



The ATLAS network is a NASA-funded telescope survey built

and operated by the University of Hawaii, with five telescopes

around the world that scan the night sky continuously to look

for objects that could threaten Earth.