October 29: The day of reckoning for 3I/ATLAS - Scientist warns of historic shift

Interstellar object 3I/Atlas has been ruled a comet by most of the astronomical community. But there is one scientist who thinks it could be an "alien mothership" coming after not just Earth, but also the other planets in the solar system. Avi Loeb says it is only a matter of a couple of days before the object reveals its true self. 3I/Atlas is approaching Mars and will be at its closest point to the red planet on October 3. Then it will travel to a point where it will go behind the Sun, becoming invisible from Earth. After vanishing from our sight, 3I/Atlas might use the Sun's gravity to fling itself towards Earth. Right now, its trajectory won't bring it anywhere near Earth, and it is expected to fly by at a safe distance. But, Loeb says things can change after October 29. If it is a piece of alien technology coming with the intention to probe us, it might use the hideout time to implement its plan and swing towards Earth. He claimed this while talking to TV actor Mayim Bialik on her YouTube show Breakdown. Loeb staunchly believes that 3I/Atlas has so many anomalies that it shouldn't be dismissed as merely a comet.

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3I/Atlas anomalies - Speed, size, light

The Harvard scientist has listed the problems with the interstellar visitor. First, its trajectory is strange. 3I/Atlas is travelling in a straight line, such that it comes close to several planets, primarily Mars and Jupiter. Second, based on the observations by the Hubble and Webb Telescopes, Loeb projects that 3I/Atlas is humongous. He says it could easily have a nucleus measuring 46 kilometres in diameter, based on its brightness. His later analysis showed that the mass of 3I/ATLAS is bigger than 33 billion tons, and that the "diameter of its solid-density nucleus must be larger than 5 kilometres." He says the chances of it being a natural object are tiny because, before finding such a huge interstellar object, we should have found thousands of much smaller space rocks.

Also Read: 3I/Atlas anomalies: Its mass is likely bigger than 33 billion tons, too large to be a comet

Another anomaly he cites is the light it is generating. Loeb thinks that this object is creating its own light, being released by its nucleus, irrespective of how much sunlight is reflecting off it. It is also racing at a speed of 200,000 km/hour, which he says is impossible for such a large object. For the longest time, 3I/Atlas didn't have a tail. A comet develops a tail as it comes closer to the Sun because of a process called outgassing. But none of the telescopes picked up a cometary tail. Earlier in September, the Gemini Telescope in Chile saw the object developing a tail.

Loeb calls on world leaders to be prepared for 3I/Atlas

Loeb has called on governments across the world to be prepared for a scenario where 3I/Atlas actually turns out to be an alien spacecraft. It is slated to reappear in early December after hiding in the Sun's glare. At its closest point, it will be 273 million kilometres. However, if it does use the Sun's gravity, like Loeb suggests, that day might come sooner than expected.