For the first time, organic molecules have been detected in an interstellar object.

The interstellar object with cometary activity, 3I/Atlas, is back in the news following the announcement of the discovery of methane, thanks to analysis by the James Webb Space Telescope, operated by NASA, the European Space Agency, and the Canadian Space Agency; incidentally, the image shown here is from the James Webb, and it is very interesting because it shows us the different ways in which this space telescope can view the same object. It does so thanks to its mid-infrared instrument, MIRI, which shows us the interstellar object at three different wavelengths of light and, in this way, also gives us an indication of where the various gases are located, each of which, of course, has a different composition.

Water vapor extends far beyond the nucleus because much of it is released from the ice grains in the surrounding coma—the name given to the bubble of gas and dust that surrounds a comet—while carbon dioxide and methane are more concentrated near the comet’s nucleus. The James Webb Space Telescope made the observations on two separate dates in December 2025, while 3I/Atlas was already moving away from its closest approach to the Sun, which occurred on October 29, 2025, at a distance of 203 million km—roughly where Mars’s orbit is located. In other words, it never came closer to the Sun than Earth does. It never crossed Earth’s orbit.

At that time, when the James Webb Space Telescope observed 3I/Atlas, it was already moving away from the Sun on a journey that will carry it out of our solar system to continue its path through the galaxy. The space telescope’s first observation took place between December 15 and 16, when 3I/Atlas was about 330 million kilometers from the Sun, and the second observation was on December 27, when 3I/Atlas was about 380 million kilometers from the Sun. By the way, note that detail and the enormous speed at which it moves—it traveled 50 million kilometers in just 11 days—and that’s because speed is one of the defining characteristics of interstellar objects.

Because they move so fast, they cannot be captured by a star’s gravity, and this characteristic is one of the first things that distinguishes them from comets and asteroids in the solar system, which move more slowly and are trapped by the Sun’s gravity. The discovery of methane marks the first time it has been detected in an interstellar object, confirming that 3I/ Atlas is much more diverse and complex than the other two interstellar objects identified to date.

The first, 1I/ʻOumuamua, whose nature remains a subject of debate, is an enigma, but one that could be, according to various theories, anything from a solid object containing metals but also some ice, to a water-rich hydrogen comet or a block of pure nitrogen, or even extraterrestrial space debris such as a solar sail—a theory put forward by Harvard professor Abi Loeb— and while some explanations sound more plausible and others more fantastical, the truth is that currently none of them fully explains the behavior of 1I/ʻOumuamua; it remains an open case, a unicorn that is now rapidly moving away from us. Perhaps in the future, a new interstellar object will provide the solution to the enigma of 1I/ʻOumuamua.

The second interstellar object detected, 2I/Borisov, did not provide us with the answer; everyone agrees that it was a normal comet—a comet about 500 meters in diameter composed of ice—and that it behaved like a typical comet. However, 3I/Atlas, although it also behaved like a comet with its coma of gas and dust, which in fact has never allowed us to see its actual nucleus—I say this because there are many images out there created with artificial intelligence that seem to show its nucleus, but we’ve never actually seen it; we can guess what it looks like, but we’ve never really seen it—and it also had a small tail, smaller than expected, and an antitail; yes, it also had an antitail, but the thing is, comets in the solar system also have antitails, and some antitails are enormous.

All these elements are typical of the comets we also see in the solar system, but what has turned out to be most interesting and enigmatic about 3I/Atlas is what it contains—the elements it’s made of—and the fact that we’re gradually discovering new elements, such as methane in this case. I’m sure there are still more elements to be discovered, and my personal bet is that they might be even more surprising.

Thank you for visiting my blog. If you like posts about #science, #planet, #politics, #rights #crypto, #traveling and discovering secrets and beauties of the #universe, feel free to Follow me as these are the topics I write about the most. Have a wonderful day and stay on this great platform :) :)

! The truth will set us free and science is the one that is closest to the truth!

---