Comet 3I/ATLAS is older than the Solar System 

NASA confirms our most recent visitor is 10 to 12 billion years old. 

We've chatted before about the most recent visitor to our Solar System, interstellar comet 3I/ATLAS.  It's now on the way back into deep-space with possible a rendezvous with another star system many millions of years in the future. 

Earlier this week researchers announced results suggesting it was formed much earlier in the history of the Milky Way.  By interrupting the planned observing schedule of the Webb Space Telescope, a team of astronomers used its NIRSpec instrument to observe 3I/ATLAS.

These observations revealed exceptionally high levels of deuterium, about 30 times more than seen in Solar System comets. Deuterium is an isotope or type of hydrogen that has an extra neutron along with the normal proton.  These high levels of deuterium found on 3I/ATLAS points towards it being formed in a much colder part of the Milky Way. In addition, the comet would have been exposed to plenty of radiation, but not any long-term warmth that would have reprocessed its “heavy water” ice, with deuterium, into the type of H2O ice we are familiar with on Earth.

Researchers used the NIRSpec (Near-Infrared Spectrograph) instrument on NASA’s James Webb Space Telescope to map specific chemical contents of comet 3I/ATLAS as it moved away from the Sun. Image via NASA, ESA.

“This was a unique opportunity to study an ancient object from the distant galaxy, probably pre-dating our Sun and solar system,” said astro-chemist Martin Cordiner of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study. “On the one hand, we get direct insight into that distant time and place, and on the other, we learn something about how unusual our own solar system may be.”

How old is old?

It's now estimated that 3I/ATLAS formed some 10 to 12 billion years ago during a period of rapid star formation in the Milky Way. This puts this visitor at over twice the age of Sun and the rest of the Milky Way.

“For us as scientists, finding these rare isotopes is fascinating, but the bigger picture here is looking at the possibilities of prebiotic chemistry elsewhere in the galaxy,” said Stefanie Milam of NASA Goddard and co-author of the study with Cordiner. “So far, we know of only one place in the vast cosmos where chemical ingredients led to life – our solar system, our Earth. Analysis of these interstellar objects is a major step towards learning how common, or uncommon, the conditions for the evolution of life are in the universe.”

Where else has Comet 3I/ATLAS been?

We don't have enough information about this comet to establish its full history certainty, but astronomers have indicated likely swung around over 60 of other stars over billions of years. 

Are we looking for other interstellar visitors?

Yes. Astronomers constantly keep an eye out for new comets as well as other types of interstellar visitors such as 'Oumuamua. Interestingly the Vera C. Rubin Observatory in Chile celebrated the first anniversary of its initial release of the wide field images. Even though this scans the entire southern night sky, it hasn't confirmed any new interstellar objects, although at least one candidate is under review.

Read more about the age of Comet 3I/ATLAS at the NASA site here.

The deepest ever images of the Milky Way's "Galactic Bulge" in visible light

60 Million Stars in this image which covers more than 20 times the area of the Full Moon

Astronomers with the European Space Agency (ESA) turned the Euclid Space Telescope to observe the centre of the Milky Way. Normally spending its time capturing wide field views of distant galaxies, the time spent photographing the heart of our home galaxy has produced a simply stunning image that shows some 60 million stars in a single frame.

Euclid covered 4.8 square degrees of the sky with this image, corresponding to 22 times the area of the full Moon as seen from Earth. The image has been rotated counterclockwise compared to the celestial projection: north is to the left and east is down. It's of particular interest to Australian astronomers as this region is almost overhead during our winter months and many of our BINTEL customers have spent hours happily imaging the Milky Way using DSLR or mirrorless cameras and star tracker mounts.

The location in the sky of this Euclid image

Read the full article here and see some more full resolution images.

World's oldest impact crater is in Australia

When you look at the Moon through even a small telescope, you can see a vast number of craters. These are round depressions that have been caused by impacts of space rocks hitting the Moon's surface.  You can even see craters within other craters, plus some appear slightly oval in shape.  There's caters like Imbrium Basin at about 1,455 km wide or even the South Pole–Aitken Basin which is some 2,500 km and one of the largest in the entire Solar System, while others visible are only a few km across.  

Most of these craters resulted from impacts that happened during the Late Heavy Bombardment (LHB). This is a hypothesized period that saw a spike in asteroid and comet impacts that scarred the Moon and inner planets including Earth which was roughly 3.9 to 4.1 billion years ago.

We sometimes have people ask us, "if the Moon is covered by craters, why don't we see them here on Earth?"

The answer is yes, we have craters on Earth, and it was certainly hit by many objects just like the Moon. However, the Moon is basically a dead body, while the Earth constantly erases its craters through weathering, plate tectonics, and water coverage. Even so, some survive.

The team from Curtin’s School of Earth and Planetary Sciences and the Geological Survey of Western Australia (GSWA) investigated rock formations at the North Pole Dome in the Pilbara region of Western Australia,

By studying zircons, a mineral that "keeps time", they've now established them as being the results of an impact of approx. 3 billion years ago, making them the oldest crater formations found on Earth. 

Read more at the Curtin University site here.

Cheers,

Earl White

BINTEL

27th June 2026