Interstellar unknowns: what can the meteorite that fell to Earth teach us about the universe

The rumble must have been incredible. The flashes of a fireball burning in the night skies of Manus Island, Papua New Guinea at 3:05 a.m. on January 8, 2014, surely lit up the sky of this Pacific Ocean paradise.

Years later, due to the high speed of the one-meter-sized object, two scientists from Harvard University who studied it, calculated that it entered our atmosphere burning with an energy equivalent to about 110 metric tons of TNT.

Will it be one more than a dozen objects of that size that fall on Earth every year and can be identified? That may have been thought by many. But because of the unusualness of this particular meteorite was the very high speed it brought and the unusual direction in which it encountered our planet, which together implied that it came from interstellar space, that is, from another solar system or distant star.

Amir Siraj and Avi Loeb, astronomers at Harvard University, retrieved the records of that atmospheric impact and found that this meteorite had reached Earth at an extraordinary speed: 210,000 km/h, well above that typical of the rocks originating in our Solar System. In addition, the trajectory of its orbit revealed that the rock did not belong to our Solar System, but had formed very far away, in “the deep interior of a planetary system or a star in the thick disk of the Milky Way galaxy,” the authors wrote

That space rock was actually the first known object from another star system, according to a communication recently published yesterday by the United States Space Command (USSC) which was classified as secret information for 3 years. The confirmation supports the discovery of the first interstellar meteorite that was initially pointed out by Harvard theoretical astrophysicist Amir Siraj and his mentor Avi Loeb in a study published on the arXiv prepress server in 2019 and that could only be read yesterday.

The object, a small meteorite measuring only 1.5 feet (0.45 meters) wide, crashed into Earth's atmosphere on January 8, 2014, after traveling through space at more than 130,000 mph (210,000 km/h), a speed that far exceeds the average speed of meteors orbiting within the solar system , according to a 2019 study of the object published in the arXiv prepress database, which argued that the speed of this rock, along with the trajectory of its orbit, proved with 99% certainty that the object had originated far beyond our solar system. But despite its almost certainty, the team's article was never peer-reviewed or published in a scientific journal, as some of the data needed to verify its calculations were considered classified by the US government.

Now, USSC scientists have officially confirmed the team's findings. In a memo dated March 1 and shared on Twitter on April 6, Lieutenant General John E. Shaw, deputy commander of the USSC, wrote that the 2019 fireball analysis was “accurate enough to confirm an interstellar trajectory.”

This confirmation retroactively makes the 2014 meteorite the first interstellar object ever detected in our solar system. The detection of the meteor predates the discovery of 'Oumuamua, a cigar-shaped object that also moves too fast to have originated in our solar system. Unlike the 2014 meteorite, 'Oumuamua was detected far from Earth and is already leaving the solar system, according to the latest data released by NASA). The same thing happened with the second object classified as interstellar, which is Comet Borisov.

“We are living in a time when a lot of research is being done on smaller bodies of the solar system. This is a major international effort by a large astronomical community that searches for small space bodies through various tracking programs. To track such an object, it must be followed over time and thus calculate its speed and trajectory. If it was confirmed that this meteorite that hit the Pacific Islands is an object that came from another solar system, it would be something impressive and a great scientific contribution to knowing more about the universe,” the doctor of astronomy Patricio Zain of the Faculty of Astronomical Sciences told Infobae. and Geophysics, of the National University of La Plata.

“So far humanity has detected two interstellar objects such as Oumuamua and Borisov. But having a fragment of an object that came from another solar system and analyzing it in a laboratory would be something fantastic that can give us a lot of information about other solar systems, other planets and stars. By analyzing their material, you can study the chemical composition of something that did not form like Earth. This meteorite can tell the story of how it formed around another star,” Zain added.

“The thing about interstellar objects is that our solar system is similar to the other solar systems that exist in the universe. Just as ours has asteroids that roam the same, so do the others. And sometimes, they can escape from it due to gravitational reasons and reach other solar systems, which is why they are called interstellar. With this new object we would have 3 interstellar objects until now, if confirmed,” astronomer Claudio Martínez explained to Infobae.

He added of the possible discovery: “The importance of this is that the more we know about other solar systems, the more we can learn from ours. The better we have an idea of how these objects form and how they behave when we are close to another star, the better we will know about our solar system to appreciate whether what we have is unique or something similar to what exists beyond our Sun. If you only have reference to nearby objects in our solar system and don't know much about those that orbit another star, you don't know if what you have is very special or similar to others. Therefore, having a sample, it can be analyzed and would become a huge source of information. But unfortunately because it fell into the ocean, it's going to be difficult to place it on the ocean floor.”

Amir Siraj, a theoretical astrophysicist at Harvard University and lead author of the 2019 paper, explained that he still intends to publish the original study, so that the scientific community can pick up where he and his colleagues left off. Because the meteorite ignited over the South Pacific Ocean, it is possible that fragments of the object have landed in the water and have since nested on the seabed.

Siraj and study co-author Avi Loeb, who serves as professor of science Frank B. Baird, Jr. at Harvard University, were inspired to search for possible interstellar fireballs after the discovery of 'Oumuamua, an interstellar object measuring about 1080 meters long and 80 meters wide, which was seen coming out of the solar system in 2017. Loeb, who speculated that 'Oumuamua might have been a piece of alien technology, suggested that Siraj review a database of fireballs and meteorite impacts administered by NASA's Near Center for Earth Objects (CNEOS).

“It was very fast, so I thought, 'My God, this could be an interstellar meteorite, '” Siraj said. While locating these remnants of interstellar debris can be an almost impossible task, Siraj said he is already consulting with experts on the possibility of mounting an expedition to recover them.

“The prospect of obtaining the first piece of interstellar material is exciting enough to verify this very thoroughly and talk to all the world's experts on ocean expeditions to recover meteorites,” explained Siraj, Director of Interstellar Object Studies at the Project Galileo from Harvard. He added: “I love thinking about the fact that we have interstellar material that was delivered to Earth and we know where it is. One thing I'm going to check, and I'm already talking to people, is whether it's possible to search the ocean floor off the coast of Papua New Guinea and see if we can get any fragments.”

Siraj acknowledged that the chances of such a finding are low, because the remains of the fireball that exploded probably landed in small quantities in a disparate region of the ocean, so it is difficult to track them down. “It would be a great undertaking, but we are going to analyze it in depth because the possibility of obtaining the first piece of interstellar material is exciting enough to verify this very thoroughly and talk to all the world experts on ocean expeditions to recover meteorites,” the expert concluded.

KEEP READING: