Interstellar comet 3I/ATLAS' journey through our solar system, in photos
Interstellar comet 3I/ATLAS' journey through our solar system, in photos

A mysterious interstellar comet has been taking a tour of our solar system in recent months, garnering intense interest from astronomers and space enthusiasts alike.

Comet 3I/ATLAS is only the third object ever confirmed to have entered our cosmic neighborhood from elsewhere in the galaxy, and the rare visit has been documented by a host of satellites, space telescopes, orbiters and even rovers.

The most recent photos of 3I/ATLAS, released last week, come from a Jupiter-bound spacecraft operated by the European Space Agency and from NASA’s Hubble Space Telescope. The new images add to a growing collection that has fostered intrigue around the interstellar object (though there is no evidence that the object is alien technology, as some have wondered).

The comet reached its closest point to the sun at the end of October and will fly by Earth on Dec. 19, staying at a safe distance of about 170 million miles away.

Here are some of the best and most interesting photos of the comet captured so far.

A gif showing a comet moving through the sky, four yellow lines point to the comet (ATLAS / University of Hawaii / NASA)
This animation shows the observations of comet 3I/ATLAS when it was discovered on July 1, 2025. (ATLAS / University of Hawaii / NASA)

Comet 3I/ATLAS was first detected in July by the Asteroid Terrestrial-Impact Last Alert System (ATLAS) in Rio Hurtado, Chile. The NASA-funded survey telescope (made up of two telescopes in Hawaii, one in Chile and a fourth in South Africa) is designed to scan for asteroids that could pose a threat to Earth.

When it was first spotted, the comet was about 420 million miles away.

Interstellar comet 3I/ATLAS. (David Rankin / Saguaro Observatory)
Interstellar comet 3I/ATLAS. (David Rankin / Saguaro Observatory)

Until now, the only other two objects confirmed to have entered our solar system from elsewhere in the galaxy were the cigar-shaped Oumuamua in 2017 and comet 2I/Borisov in 2019.

A gif showing a moving interstellar comet (NASA / SPHEREx)
NASA’s SPHEREx observed interstellar comet 3I/ATLAS from Aug. 7 to Aug. 15. (NASA / SPHEREx)

NASA’s SPHEREx observatory (short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) trained its eyes on Comet 3I/ATLAS from Aug. 7 to Aug. 15, providing scientists with new details about the object’s size, physical properties and chemical composition.

At the time, the comet was about 290 million miles away from the sun. The SPHEREx observations revealed the comet’s coma, a hazy cloud of gas and dust akin to an atmosphere that surrounds its nucleus. Researchers determined that the coma contained an abundance of ice water and carbon dioxide, similar to the chemistry of comets formed in our solar system.

Interstellar Comet (NoirLab via AP file)
A comet streaking across a star field above the International Gemini Observatory near La Serena, Chile. (NoirLab via AP file)

In late August, the Gemini South telescope in Chile captured what were the most detailed images of the comet at the time. The photos, released in September, showed an extended coma of dust and gas around the icy nucleus.

Astronomers suggested that 3I/ATLAS was becoming more active as it approached the sun, judging by the object’s lengthy tail, which appeared more elongated in the telescope’s images compared to previous sightings.

An image of a comet (The European Space Agency)
The European Space Agency's ExoMars Trace Gas Orbiter image of interstellar comet 3I/ATLAS, as it passed close to Mars. (The European Space Agency)

The European Space Agency released new images of the comet in October, which were taken by a spacecraft in orbit around Mars. The ExoMars Trace Gas Orbiter, jointly operated by ESA and Russia’s Federal Space Agency, observed the comet for about a week beginning on Oct. 1.

A comet moves in space (The European Space Agency)
The interstellar comet 3I/ATLAS as it moves. (The European Space Agency)

The photos show a fuzzy white dot — the center of the comet — moving against a dark and starry expanse. When the images were taken, 3I/ATLAS was roughly 18.6 million miles from the orbiter.

The interstellar comet 3I/ATLAS, circled in the center, as seen by NASA’s Lucy spacecraft. This image was made by stacking a series of images taken Sept. 16 as the comet was zooming toward Mars. (NASA / Goddard / SwRI / JHU-APL)
The interstellar comet 3I/ATLAS, circled in the center, as seen by NASA’s Lucy spacecraft. This image was made by stacking a series of images taken Sept. 16 as the comet was zooming toward Mars. (NASA / Goddard / SwRI / JHU-APL)

After weeks of delays because of the government shutdown, NASA released a trove of 3I/ATLAS photos taken by various spacecraft from late September through mid-October.

The comet mostly appeared as an illuminated dot, but some images were detailed enough to pick up its tail as a faint, elongated smudge.

Observations of comet 3I/ATLAS from Sept. 28 to Oct. 10 from the PUNCH satellites in low-Earth orbit, when the comet was 231 million to 235 million miles away. (NASA / Southwest Research Institute)
Observations of comet 3I/ATLAS from Sept. 28 to Oct. 10 from the PUNCH satellites in low-Earth orbit, when the comet was 231 million to 235 million miles away. (NASA / Southwest Research Institute)

Among the NASA missions that observed the comet relatively up-close were the sun-watching PUNCH satellites, the Solar and Heliospheric Observatory, the Lucy space probe, the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission and the Perseverance Rover on the surface of Mars.

An interstellar comet is seen in the sky, two images superimposed (NASA, ESA, STScI, D. Jewitt (UCLA) / M.-T. Hui (SAO) / J. DePasquale (STScI))
NASA’s Hubble Space Telescope reobserved interstellar comet 3I/ATLAS Nov. 30, with its Wide Field Camera 3 instrument. (NASA, ESA, STScI, D. Jewitt (UCLA) / M.-T. Hui (SAO) / J. DePasquale (STScI))

Late last month, NASA’s Hubble Space Telescope tracked 3I/ATLAS when it was approximately 178 million miles away from Earth. Hubble’s instruments recorded the moving comet as a luminous point while the background stars appeared as streaks of light. NASA released the images on Thursday and said it intends to gather more data on 3I/ATLAS in the coming months as the comet moves out of the solar system.

The European Space Agency released new photos of 3I/ATLAS the same day, adding to our understanding of the interstellar object’s appearance, composition and behavior. The agency’s Jupiter Icy Moons Explorer, or Juice — a spacecraft en route to Jupiter to study the planet and three of its large moons — gathered the data shortly before the spacecraft’s closest approach to the comet on Nov. 4, when it flew within about 41 million miles.

The photos from Juice showed the glowing halo of the comet’s coma and revealed the possibility that it has two tails. The first, the comet’s “plasma tail,” is made up of ionized or electrically charged gas and can be seen extending toward the top of the frame. The second, the comet’s “dust tail,” is made up of gas, dust and other tiny solid particles; it stretches to the lower left of the frame.

The European Space Agency expects to retrieve additional data from Juice’s science instruments in February.

This article was originally published on NBCNews.com

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