3I/ATLAS Interstellar Comet Live Tracker: Will 3I/ATLAS reappear again? Here's what happens to the comet next

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Going by Hubble Space Telescope observations made in August 20, astronomers said the diameter of the comet's nucleus is not less than 1444 feet and not greater than 5.6 kilometers, said NASA.

Skywatchers will need a large telescope — at least 8 inches (20 cm) in diameter — to spot it.

3I/ATLAS will never be visible to the naked eye, remaining a faint but fascinating visitor for astronomers.

Astronomers have said that 3I/ ATLAS have been observed with a nucleus and a coma (a bright cloud of gas and dust surrounding a comet as it approaches the Sun), thus making it a comet, and not an asteroid.

NASA said the comet does not follow a closed orbital path around the Sun, meaning it did not originate in our solar system. The space agency said that the comet is passing through our solar system and will continue its journey into interstellar space.

3I/ATLAS Interstellar Comet Live Tracker: According to the data collected on 20 August 2025, the diameter of the comet is 5.6 kilometres, while it is 440 meters across.

“The upper limit on its diameter is 3.5 miles (5.6 kilometres), though it could be as small as 1,444 feet (440 meters) across,” according to the NASA website.

According to NASA, the 3I/ATLAS formed in another star system and was somehow ejected into interstellar space, which is the space between the stars. The comet was in the orbit of Jupiter when it was observed.

Comets are usually named after their discoverers, mentioned NASA. So 'ATLAS' stands for the ATLAS survey team – the discoverer, ‘I’ is for interstellar, and ‘3’ represents the third known interstellar object.

Comet 3I/ATLAS has left scientists surprised by brightening at an unexpectedly rapid pace as it made its closest approach to the sun. As per reports, experts are still studying the object and are yet to discover why it happened

The 3I/ATLAS comet is expected to reappear around November 11, emerging in the eastern predawn sky.

Earlier, a Hubble image of the Comet 3I/ATLAS showed that the comet with a teardrop-shaped cocoon of dust coming off its solid, icy nucleus.

According to The Sky's live tracker, comet 3I/ATLAS is in the constellation of Virgo, at a distance of 340,271,040.2 kilometers from Earth.

3I/ATLAS Interstellar Comet Live Tracker: US-based space organisation, NASA, is tracking the 3I/ATLAS interstellar comet through its deep space telescopes namely — Hubble, Webb, and SPHEREx.

3I/ATLAS Interstellar Comet Live Tracker: The 3I/ATLAS interstellar comet is set to leave out solar system behind after its passed behind the Sun in October. The comet will pass Jupiter in March 2026 on its way out of the solar system.

“The comet is on course to pass behind the Sun in late October, and venture past Jupiter in March 2026, on its way out of our solar system,” said NASA in its website.

3I/ATLAS Interstellar Comet was first discovered on July 1, 2025. The NASA-funded ATLAS survey telescope in Chile reported that the comet originated from interstellar space. Here's a glimpse

The 3I/ATLAS was first discovered on July 1, 2025. The NASA-funded ATLAS survey telescope in Chile first reported that the comet originated from interstellar space.

A Hubble image of the Comet 3I/ATLAS showed that the comet with a teardrop-shaped cocoon of dust coming off its solid, icy nucleus.

Multiple visuals on social media showed the 3I/ATLAS while it made its closest approach to the sun. Here's a glimpse

Comets are usually named after their discoverers, mentioned NASA. So 'ATLAS' stands for the ATLAS survey team – the discoverer, ‘I’ is for interstellar, and ‘3’ represents the third known interstellar object.

The Comet 3I/ATLAS is expected to reappear around 11 November, emerging in the eastern predawn sky, but will not be visible to naked eye.

The European Space Agency stated that it will not send a spacecraft to investigate Comet 3I/ATLAS, citing the comet’s extreme velocity and the short timeframe before its approach as factors that make such a mission unfeasible.

Rather than sending a spacecraft, scientists reportedly plan to study 3I/ATLAS using powerful telescopes from Earth and space. The European Space Agency (ESA) announced that instruments like the Hubble and James Webb Space Telescopes will examine the comet’s dust and gas composition.

3I/ATLAS is a comet, a large icy object that develops a luminous tail when it approaches the Sun. Unlike meteorites, which are small rock or metal fragments that enter Earth’s atmosphere as "shooting stars" and impact the ground, comets remain in space and follow elongated orbits around the Sun.

No, it’s not possible to observe the event right now. According to Space.com, the comet is currently in solar conjunction, which means it’s concealed by the Sun’s glare from our point of view on Earth. It’s expected to become visible again to ground-based telescopes in late November or early December.

The interstellar comet 3I/ATLAS has astonished scientists once again — this time for its incredible age. According to astronomers, the comet is estimated to be around 7 billion years old, making it roughly twice as old as Earth.

The interstellar comet 3I/ATLAS has left scientists puzzled after unexpectedly brightening rapidly during its closest approach to the Sun. Researchers are still unsure what caused the sudden change, according to a Space.com report.

A Harvard scientist speculated that the international community should remain vigilant and formulate a defense plan if 31/ATLAS is a “black swan event" — defined as a high-impact, unpredictable event that is rare, has a major impact, and is difficult to forecast under normal circumstances but appears to be inevitable in hindsight.

Comets are tricky targets. Their glowing tails and hazy atmospheres can distort how bright they appear, making calculating their path harder. By studying 3I/ATLAS closely, scientists can practice the techniques needed to accurately measure a comet’s motion—speed, direction, and how gravity bends its course.

Comet 3I/ATLAS is a newly identified interstellar object, meaning that it comes from outside our Solar System. It is only the third of its kind ever observed, following 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019.

According to NASA, astronomers categorised Comet 3I/ATLAS as an interstellar object because of the hyperbolic shape of its orbital path. It does not follow a closed orbital path about the Sun.

Citizen scientists interested in participating in this campaign require a telescope and a passion for astronomy.

NASA and the International Asteroid Warning Network (IAWN) have launched a global observing campaign to track 3I/ATLAS. The effort will involve telescopes, research centers, and volunteers around the world, all focusing on one goal - improving how we detect and predict the movement of objects that could one day be hazardous to our planet.

The closest it will approach Earth is about 1.8 astronomical units (about 170 million miles, or 270 million kilometers). It will reach its closest point to the Sun around October 30, 2025.

NASA stated that Comet 3I/ATLAS poses no threat to Earth and will remain at a safe distance.

Comets are generally named after their discoverer(s). In this case, it was the ATLAS survey team. The letter “I” is for “interstellar,” indicating that this object came from outside our solar system.

It’s the third known interstellar object – following 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019 – hence the “3” in the name.

An official of NASA’s Center for Near Earth Object Studies (CNEOS) said Comet 3I/ATLAS came from outside our solar system. When the orbit of 3I/ATLAS is traced back in time, the comet clearly originates from outside our solar system.

"Comet 3I/ATLAS is the third known object from outside our solar system to be discovered passing through our celestial neighborhood," NASA said.

Comet 3I/ATLAS was discovered on July 1, 2025, by NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile.

On Wednesday (October 28), two researchers posted a study to the preprint server arXiv that reported comet 3I/ATLAS underwent rapid brightening ahead of perihelion.

The team estimates that, at perihelion, the comet will have brightened to roughly magnitude 9 — still too faint to be seen with the unaided eye, but bright enough to be seen by good backyard telescopes, if it were visible from Earth.

In fact, 3I/ATLAS could be the oldest comet ever seen, experts have said. One study even suggested it's around 3 billion years older than our 4.6 billion-year-old solar system.

The comet is also likely the largest interstellar object ever seen, though researchers are still pinning down its exact size. Hubble Space Telescope data suggest that 3I/ATLAS has a maximum width of about 3.5 miles (5.6 km).

By the time the comet reaches its closest point to Earth, it will be hidden behind the Sun. It is due to reappear in late November, offering astronomers another window for study. During its closest approach to the Earth, it will be on the other side of the Sun, the ESA said.

The comet will become visible again to Earth-based telescopes by early December, according to NASA, and may even be visible to spacecraft orbiting Jupiter as it makes a close approach to the gas giant in March, 2026.

NASA had earlier said that 3I/ATLAS is traveling through our solar system at “the highest velocity ever recorded for a solar system visitor.”

"This breathtaking sprint is evidence that the comet has been drifting through interstellar space for many billions of years... The longer 3I/ATLAS was out in space, the higher its speed grew," NASA said.

According to Live Science, findings so far indicate that Comet 3I/ATLAS's zooming through our solar system at speeds in excess of 130,000 mph (210,000 km/h) in an unusually flat and straight trajectory.

The potential age of 3I/ATLAS sets it apart. Formed around around ancient stars, it may carry chemical signatures from early Milky Way, preserving information about the conditions that existed long before the Sun was born.

Studying its composition could offer insights into how interstellar comets contribute to star and planet formation throughout the Galaxy.

The discovery of 3I/ATLAS marks only the third time astronomers have identified an object entering our solar system from interstellar space. Unlike previous visitors 1I/ʻOumuamua (2017) and 2I/Borisov (2019), this comet is thought to have originated from a completely different region of Milky Way Galaxy.

Astronomers have identified 31/ATLAS, an ancient, ice-rich interstellar comet potentially older than our solar system. Discovered by the University of Oxford, its origin in the Milky Way's thick disk offers a unique glimpse into early galactic processes. Scientists anticipate studying its composition as it nears the Sun, providing vital clues about the formation of stars and planetary systems.

Comet 3I/ATLAS was first spotted on 1 July 2025 by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Río Hurtado, Chile.

Harvard University professor, Avi Loeb, has requested NASA to release scientific data on 3I/ATLAS.

The professor said that NASA withheld for four weeks the HiRISE camera images captured by the Mars Reconnaissance Orbiter on October 2–3, 2025, when the interstellar object 3I/ATLAS passed within 30 million km of Mars. The images, finally released, hold major scientific value with a spatial resolution of 30 km per pixel—about three times sharper than the best publicly available Hubble image from July 21, 2025.

The interstellar comet 3I/ATLAS has a thick irradiated crust that no longer resembles its home star system, simulations and James Webb Space Telescope observations have found.

Harvard professor Avi Loeb has suggested that interstellar comet 3I/ATLAS may not be entirely natural after it showed non-gravitational acceleration while nearing the Sun. NASA’s data revealed the comet moved in unusual directions and glowed bright blue, unlike typical red comets.

3I/ATLAS Interstellar Comet Live Tracker: According to the official data, the 3I/ATLAS interstellar comet will reappear on the other side of the Sun by early December 2025.

“It will reappear on the other side of the Sun by early December 2025, allowing for renewed observations,” said NASA.