Interstellar comet 3I/ATLAS to make its closest approach to Earth: How to track and watch it live

Spotting a visitor like 3I/ATLAS feels like winning the cosmic lottery, bringing a sense of thrill along with plenty of speculation about it being an alien body.

Ever since the visitor entered our solar system, it has attracted numerous images from space telescopes, along with wild alien theories that NASA quickly shut down.

As this visitor is now set to pass Earth at its closest point, it’s the perfect time to track it and wonder what secrets this icy wanderer might hold.

What is 3I/ATLAS?

This third confirmed interstellar object, spotted by Chile’s ATLAS telescope in July 2025, comes from beyond our solar system. It is a comet with an icy nucleus, a coma of gas and dust, and glowing tails, unlike rocky asteroids. Named 3I for being the third such object after ‘Oumuamua (2017) and Borisov (2019), it drifts in from the direction of Sagittarius, as confirmed by NASA’s Jet Propulsion Laboratory and the Minor Planet Center.

NASA released images of the comet

NASA released stunning images on November 19, 2025, showing 3I/ATLAS’ active coma and tails. Hubble captured it on November 30 from about 178 million miles away, with streaked stars caused by tracking the comet’s motion. ESA’s JUICE probe near Jupiter also snapped images between November 2 and 25, revealing a hyperactive phase after its close approach to the Sun.

How to track 3I/ATLAS live

3I/ATLAS will make its closest pass to Earth on December 19, remaining at a safe distance of about 170 million miles. It is too faint to be seen with the naked eye, so a small telescope or binoculars are recommended. It can be spotted in the pre-dawn skies near Virgo and Leo through spring 2026, with the best views from dark locations. Live tracking is also available via NASA’s Eyes on the Solar System and the Virtual Telescope Project livestream.

What is the size and speed of the comet?

Estimates place the nucleus between about 1,400 feet and 3.5 miles wide, based on Hubble and ESA data. At discovery, it was travelling at roughly 137,000 miles per hour, accelerating as it approached the Sun before slowing down on its outward journey. Active outbursts of gas and dust as it warms confirm its cometary nature rather than that of an asteroid.

Theories that 3I/ATLAS is an alien probe

Conspiracy theories have labelled it an alien spacecraft, a claim popularly discussed by Harvard scientist Avi Loeb. However, NASA has firmly rejected this idea, stating it is a natural comet. In November 2025, Associate Administrator Nicola Fox said, “We certainly haven’t seen any technosignatures.” According to observations from Hubble, Webb, and ESA spacecraft, it is simply ice and rock from another star system, with no evidence of extraterrestrial technology.