As interstellar object 3I/ATLAS approaches its closest point to the Sun next month, the mysterious visitor continues to
fascinate astronomers.
The object, which is broadly believed to be a comet that came to us from outside the solar system, has already been
observed changing shape. Its tail has grown longer, and its coma — a large atmosphere of gas and dust that surrounds its nucleus — has become more pronounced. Those are expected characteristics from a comet ripping by the Sun at ludicrous speeds, though numerous readings by sensitive space telescopes have also found it to have
unusual properties that will be studied for years to come.
In the latest twist, this week, comet hunter Michael Jäger and his colleagues "took advantage of the total lunar eclipse to take a deep image of Comet 3I/ATLAS under the dark skies of Namibia," according to a
recent forum exchange.
Their observations showed that the object's coma has now transitioned from giving off red light to green, yet another fascinating wrinkle in the rare interstellar visitor's odyssey through our solar system.
As Harvard astronomer and noted alien hunter Avi Loeb
pointed out in a recent blog post on the findings, this could be due to a "steep rise in the production of cyanide."
Scientists
hypothesize that the production of the chemical, alongside nickel, are increasing dramatically as 3I/ATLAS approaches the Sun.
Data
by the ATLAS telescope team, which first spotted the object and after which the space rock is named, suggests that the object's "anomalous evolution" is shifting from "scattering of sunlight by dust lifted from a reddened surface to the production of small, optically bright icy grains, which changed the opacity of the plume of materials shed off by 3I/ATLAS," per Loeb.