A visitor from another star system is creating excitement in the astronomy community. The comet 3I/ATLAS which was first spotted in July 2025 contains chemical clues that scientists can use to study the formation of other planets, existence of aliens and icy bodies in space.
The Atacama Large Millimeter/submillimeter Array (ALMA) in Chile allows researchers to discover that the comet emitted extremely high amounts of methanol which is a type of alcohol through its luminous gas halo.
National Radio Astronomy Observatory (NRAO) Lead Researcher Nathan Roth said, “Observing 3I/ATLAS is like taking a fingerprint from another solar system. The details reveal what it’s made of, and it’s bursting with methanol in a way we just don’t usually see in comets in our own solar system.”
ALMA detected strong signals of methanol (CH3OH) in the comet’s expanding coma, while hydrogen cyanide mainly streams from the nucleus. Methanol is released both from the nucleus and icy grains acting like miniature comets, the first time such behavior has been mapped in an interstellar object.
The high methanol content indicates that 3I/ATLAS likely formed in colder conditions or had a different chemical inventory from our solar system. Methanol is known to be present in comets and to be produced on icy dust grains in interstellar clouds. However, its content is much higher in 3I/ATLAS compared to those found in comets in our solar system.
The comet’s tail and gas jets emit glowing X-rays as solar winds’ particles hit the escaping materials, providing more hints about the composition and structure of the comet.
Discovered by the Asteroid Terrestrial-Impact Last Alert System in July 2025, 3I/ATLAS is the third known object from outside our solar system after ‘Oumuamua in 2017 and 2I/Borisov in 2019.
American University Professor Nathan Roth said that studying the comet is a rare chance to see how building blocks of other planets were made billions of years ago.