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Interstellar meteor confirmed to have collided with Earth in 2014, researchers say – CTV News

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One meteor travelled quite a long way from home to visit Earth.

Researchers discovered the first known interstellar meteor to ever hit Earth, according to a recently released United States Space Command document. An interstellar meteor is a space rock that originates from outside our solar system — a rare occurrence.

This one is known as CNEOS 2014-01-08, and it crash-landed along the northeast coast of Papua New Guinea on January 8, 2014.

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The finding came as a surprise to Amir Siraj, who identified the object as an interstellar meteor in a 2019 study he coauthored while an undergraduate at Harvard University.

Siraj was investigating ʻOumuamua, the first known interstellar object in our solar system that was found in 2017, with Abraham Loeb, professor of science at Harvard University.

Siraj decided to go through NASA’s Center for Near Earth Object Studies database to find other interstellar objects and found what he believed to be an interstellar meteor within days.

A NEED FOR SPEED

The meteor’s high velocity is what initially caught Siraj’s eye.

The meteor was moving at a high speed of about 28 miles per second (45 kilometres per second) relative to Earth, which is moving at around 18.6 miles per second (30 kilometres per second) around the sun. Because researchers measured how fast the meteor was moving while on a moving planet, the 45 kilometres per second was not actually how fast it was going.

The heliocentric speed is defined as the meteor’s speed relative to the sun, which is a more accurate way to determine an object’s orbit. It’s calculated based on the angle at which a meteor hits the Earth. The planet moves in one direction around the sun, so the meteor could have hit Earth head-on, meaning opposite the direction the planet is moving, or from behind, in the same direction the Earth is moving.

Since the meteor hit the Earth from behind, Siraj’s calculations said the meteor was actually traveling at about 37.3 miles per second (60 kilometres per second) relative to the sun.

He then mapped out the trajectory of the meteor and found it was in an unbound orbit, unlike the closed orbit of other meteors. This means that rather than circling around the sun like other meteors, it came from outside the solar system.

“Presumably, it was produced by another star, got kicked out of that star’s planetary system and just so happened to make its way to our solar system and collide with Earth,” Siraj said.

DIFFICULTY GETTING PUBLISHED

Loeb and Siraj have been unable to get their findings published in a journal because their data came from NASA’s CNEOS database, which doesn’t divulge information such as how accurate the readings are.

After years of trying to obtain the additional information needed, they received official confirmation that it was, in fact, an interstellar meteor, from John Shaw, deputy commander of the U.S. Space Command. The command is a part of the U.S. Department of Defense and is responsible for military operations in outer space.

“Dr. Joel Mozer, the Chief Scientist of Space Operations Command, the United States Space Force service component of U.S. Space Command, reviewed analysis of additional data available to the Department of Defense related to this finding. Dr. Mozer confirmed that the velocity estimate reported to NASA is sufficiently accurate to indicate an interstellar trajectory,” wrote Shaw in the letter.

Siraj had moved onto other research and almost forgotten about his discovery, so the document came as a shock.

“I thought that we would never learn the true nature of this meteor, that it was just blocked somewhere in the government after our many tries, and so actually seeing that letter from the Department of Defense with my eyes was a really incredible moment,” Siraj said.

A SECOND CHANCE

Since receiving the confirmation, Siraj said his team is working to resubmit their findings for publication in a scientific journal.

Siraj would also like to put a team together to try and retrieve part of the meteor that landed in the Pacific Ocean but admitted it would be an unlikely possibility due to the sheer size of the project.

If researchers were able to get their hands on the “holy grail of interstellar objects,” Siraj said it would be scientifically groundbreaking in helping scientists discover more about the world beyond our solar system.

NASA and US Space Command did not initially respond for comment.

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Giant prehistoric salmon had tusk-like teeth for defence, building nests

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The artwork and publicity materials showcasing a giant salmon that lived five million years ago were ready to go to promote a new exhibit, when the discovery of two fossilized skulls immediately changed what researchers knew about the fish.

Initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and had led researchers to mistakenly suggest the fish had fang-like teeth.

It was dubbed the “sabre-toothed salmon” and became a kind of mascot for the Museum of Natural and Cultural History at the University of Oregon, says researcher Edward Davis.

But then came discovery of two skulls in 2014.

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Davis, a member of the team that found the skulls, says it wasn’t until they got back to the lab that he realized the significance of the discovery that has led to the renaming of the fish in a new, peer-reviewed study.

“There were these two skulls staring at me with sideways teeth,” says Davis, an associate professor in the department of earth sciences at the university.

In that position, the tusk-like teeth could not have been used for biting, he says.

“That was definitely a surprising moment,” says Davis, who serves as director of the Condon Fossil Collection at the university’s Museum of Natural and Cultural History.

“I realized that all of the artwork and all of the publicity materials and bumper stickers and buttons and T-shirts we had just made two months prior, for the new exhibit, were all out of date,” he says with a laugh.

Davis is co-author of the new study in the journal PLOS One, which renames the giant fish the “spike-toothed salmon.”

It says the salmon used the tusk-like spikes for building nests to spawn, and as defence mechanisms against predators and other salmon.

The salmon lived about five million years ago at a time when Earth was transitioning from warmer to relatively cooler conditions, Davis says.

It’s hard to know exactly why the relatives of today’s sockeye went extinct, but Davis says the cooler conditions would have affected the productivity of the Pacific Ocean and the amount of rain feeding rivers that served as their spawning areas.

Another co-author, Brian Sidlauskas, says a fish the size of the spike-toothed salmon must have been targeted by predators such as killer whales or sharks.

“I like to think … it’s almost like a sledgehammer, these salmon swinging their head back and forth in order to fend off things that might want to feast on them,” he says.

Sidlauskas says analysis by the lead author of the paper, Kerin Claeson, found both male and female salmon had the “multi-functional” spike-tooth feature.

“That’s part of our reason for hypothesizing that this tooth is multi-functional … It could easily be for digging out nests,” he says.

“Think about how big the (nest) would have to be for an animal of this size, and then carving it out in what’s probably pretty shallow water; and so having an extra digging tool attached to your head could be really useful.”

Sidlauskas says the giant salmon help researchers understand the boundaries of what’s possible with the evolution of salmon, but they also capture the human imagination and a sense of wonder about what’s possible on Earth.

“I think it helps us value a little more what we do still have, or I hope that it does. That animal is no longer with us, but it is a product of the same biosphere that sustains us.”

This report by The Canadian Press was first published April 24, 2024.

Brenna Owen, The Canadian Press

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Giant prehistoric salmon had tusk-like spikes used for defence, building nests: study

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A new paper says a giant salmon that lived five million years ago in the coastal waters of the Pacific Northwest used tusk-like spikes as defense mechanisms and for building nests to spawn.

The initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and led researchers to suggest the fish had fang-like teeth.

The now-extinct fish was dubbed the “saber-tooth salmon,” but the study published in the peer-reviewed journal PLOS One today renames it the “spike-toothed salmon” and says both males and females possessed the “multifunctional” feature.

Study co-author Edward Davis says the revelation about the tusk-like teeth came after the discovery of fossilized skulls at a site in Oregon in 2014.

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Davis, an associate professor in the department of earth sciences at the University of Oregon, says he was surprised to see the skulls had “sideways teeth.”

Contrary to the belief since the 1970s, he says the teeth couldn’t have been used for any kind of biting.

“That was definitely a surprising moment,” Davis says of the fossil discovery in 2014. “I realized that all of the artwork and all of the publicity materials … we had just made two months prior, for the new exhibit, were all out of date.”

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SpaceX sends 23 Starlink satellites into low-Earth orbit

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April 23 (UPI) — SpaceX launched 23 Starlink satellites into low-Earth orbit Tuesday evening from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida.

Liftoff occurred at 6:17 EDT with a SpaceX Falcon 9 rocket sending the payload of 23 Starlink satellites into orbit.

The Falcon 9 rocket’s first-stage booster landed on an autonomous drone ship in the Atlantic Ocean after separating from the rocket’s second stage and its payload.

The entire mission was scheduled to take about an hour and 5 minutes to complete from launch to satellite deployment.

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The mission was the ninth flight for the first-stage booster that previously completed five Starlink satellite-deployment missions and three other missions.

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