New ‘spacecraft’ 3I/Atlas photographs present ‘anti-tail’ for the primary time as Earth method looms
The Manhattan-sized space rock hurtling through space has given off a large “anti-tail” after passing behind the sun, which is expected from comets, but not of this size, a boffin believe
A mystery object feared to be an alien space ship heading to Earth has displayed an “anti-tail” for the first time as it speeds away from the sun. New pictures reveal the “interstellar anomaly” known as 3I/ATLAS as it hurtles across the solar system with a “complex tail” after passing behind the sun last week.
And amateur astronomer Michael Jaeger of Austria, who has been tracking 3I/ATLAS since last Tuesday, captured a spray of four or five plumes. He told SpaceWeather.com: “We have something unusual to report. 3I/ATLAS showed a complex tail structure early this morning.”
He noted that during the exposure, the comet was just seven to 10 degrees above the horizon, but confirmed that the comet remains on its predicted trajectory.
Most boffins think it’s a comet that has been travelling for billions of years, but theoretical physicist Avi Loeb has previously warned it could be an “extraterrestrial artefact” about to make first contact.
He told NBC News: “We see more than seven jets coming out of this object. Of course there are two possibilities that we have considered all along.
“That these jets are naturally produced out of ice on the surface of the rock. The second possibility is that they might be thrusters on a technological space craft. So how do we tell the difference?
“Well if it’s a natural object then we know the temperature on the surface of the rock, given its distance from the sun and that gives the characteristic speed of any volatiles that get sublimated and objected from those pockets of ice.
“So knowing the speed, we we can see how far these jets go into the solar wind. We know the properties of the solar wind and these jets appear to be in the direction of the sun and they go a million kilometres away rom the object.
“So knowing the properties, the speed an the density of the solar wind, we can infer how much mass is being carried by these jets. I did some calculation and I found of the order of five billion tonnes of material.
“Now we ask how much energy is needed to sublimate ice with such a large mass and the answer is – if its carbon dioxide – it needs a surface area of an object that is 20km in diameter, much bigger than we estimated for the actual 3/atlas from the Hubble image captured back in July.”
He said if it was a natural comet, it may have broken up into hundreds of pieces, but we do not yet have a clear enough image to confirm this.
He added: “However, if it is a technological object and we’re talking about technological thrusters, those usually eject gas at a much higher speed. Rockets eject gas at 10 times faster than expected from volitiles from the surface of a comet.
“And Iron thrusters go up to 100 times the speed of those natural pockets of ice. So we would expect much less mass to be carried on these jets at much higher speed.
“The coming weeks will tell us the answer because if this object is broken up, we will see the pieces and we will see slow moving jets with a lot of mass in them.
“On the other hand, if it’s a tech object, we will see very fast jets with much less material in them and the object maintains its integrity as it moves along.”
Discovered on July 1, 2025, Comet 3I/ATLAS is the third known object from outside our solar system to be discovered hurtling through space.
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