The interstellar comet 3I/ATLAS, most astronomers believe is a comet originating from an unknown star system far beyond our own. It is the only third interstellar object ever detected in our solar system. It is the largest, fastest-moving, and quite likely the oldest interstellar object ever seen.
What will happen when comet 3I/ATLAS reaches closest to Sun?
Comet 3I/ATLAS was confirmed by NASA in early July and this Wednesday (Oct. 29), 3I/ATLAS will reach perihelion — its closest point to the sun — before beginning its months-long departure from our cosmic neighborhood. On October 29, the mysterious visitor will be at perihelion, a point where things could dramatically change for the comet. While scientists worldwide are certain that it is a comet, theories suggesting it could be an alien spacecraft are also circulating.
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Comets usually begin to outgas as they approach the Sun, where intense heat and solar radiation cause their icy surfaces to sublimate. As the ice within the comet’s nucleus turns into gas, it propels dust and vapor outward, forming a glowing coma that grows larger and brighter. This outflow of material also creates the comet’s distinct tail, which always extends away from the Sun.
According to Live Science, comet 3I/ATLAS is set to reach its perihelion this week, coming as close as 1.4 astronomical units—or about 130 million miles (210 million kilometers)—from the Sun, per NASA. As it nears this point, the comet is expected to release gas at an accelerated rate.
When it becomes visible to telescopes again in early November, it could appear larger and brighter than it did two months ago. Observatories on Earth, in orbit, and even spacecraft en route to Jupiter are preparing to capture the spectacle, as 3I/ATLAS makes its final journey out of our solar system.ALSO READ: Comet 3I/ATLAS is the largest, fastest-moving, oldest object ever seen: Can probes catch the tail of Manhattan-sized space visitor?
Is NASA hiding something?
Harvard scientist Avi Loeb has sparked widespread curiosity online by warning people to “take vacations before October 29,” suggesting that NASA may be withholding critical information about a mysterious interstellar object passing through our solar system. Loeb — who maintains that the object could be of alien origin ever since its July discovery — told “Elizabeth Vargas Reports” that he was concerned with the size of 31/ATLAS, which he inferred could weigh 33 billion tons based on Webb Telescope data.“It’s at least a thousand times more massive than the previous interstellar objects we’ve seen,” the astrophysicist declared. “And the question is, why is such a giant object delivered to our inner solar system, when we saw only small ones before?”
Loeb speculated that the international community should remain vigilant and formulate a defense plan in the event that 31/ATLAS is a ” black swan event,” defined as a high-impact event that is difficult to forecast under normal circumstances but appears to be inevitable in hindsight. Speaking to The New York Post, he said, “There is only one place where that is known to exist and that is in industrially produced nickel alloys. This was never observed for any other object.”
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Loeb has said that 3I/ATLAS behaves differently from typical comets. Instead of releasing gas away from the Sun, its jet points directly toward it. He contends that its trajectory and chemical composition may be indicative of purposeful design over happenstance natural forces. Loeb has also expressed scepticism about NASA’s candour, suggesting the agency is suppressing some information and photographs about the object.
The International Asteroid Warning Network added 3I/ATLAS to its list of targets earlier this week, and began monitoring the object for scientific purposes. The group wrote on its website: “While it poses no threat, comet 3I/ATLAS present a great opportunity for the IAWN community to perform an observing exercise due to its prolonged observability from Earth and its high interest to the scientific community.”
Researchers around the globe are waiting with bated breath for the images taken earlier this month by NASA’s HiRISE camera — the highest resolution images of 3I/ATLAS yet — onboard the Mars orbiter when the object came within 12 million miles of the Red Planet. They have yet to be shared by the US space agency due to the ongoing government shutdown.