Research suggests that interstellar space clouds caused ice ages

The Pleistocene Era – with its glaciers, woolly mammoths and Neanderthals – still looms large in Earth’s rearview mirror, having ended just 12,000 years ago. Now, a team of researchers hypothesizes that hundreds of thousands of years of our planet’s history may have been cooled by a cloud in space that briefly shielded Earth from the warm glow of the sun.

Researchers suggest that about two million years ago, an interstellar cloud interfered with the solar system in such a way that it briefly put Earth and other planets outside the Sun’s range. Heliosphere, a bubble of charged particles from our host star that today forms an amorphous shell around the system. It was their research published Today in Nature Astronomy.

“This paper is the first to quantitatively show that there was a collision between the Sun and something outside the solar system that would affect Earth’s climate,” Merav Ofer, an astrophysicist at Boston University and lead author of the study, said in an email. To Gizmodo. Over added that the team is “still trying to measure its size using modern climate models,” but with the increase in hydrogen and dust, “the Earth will have entered an ice age.”

The Ophir team modeled the data from HI4PI scan It found that our solar system may have passed through the local band of cold clouds in the Lynx constellation between 2 million and 3 million years ago. The Ice Age began about 2.6 million years ago. The statement noted that it is not possible to say with certainty whether such cold clouds could trigger an ice age, but more evidence of clouds manipulating the heliosphere may clarify what kind of effects they might have on Earth.

The team’s model revealed that in such a pass, the heliosphere surrounding Earth and its neighboring planets would shrink to about 0.22 astronomical units, or less than a quarter of the distance between Earth and the Sun. To put that in perspective, ESA estimates The closest boundary of the heliosphere today is located about 100 astronomical units from the Sun, about twice the distance from the Kuiper Belt.

The team hypothesized that outside the heliosphere, Earth would have been exposed to iron and plutonium in the interstellar medium. Their timeline aligns with a slight increase in the amount of plutonium-244 and iron-60, two isotopes of the elements in question that are known to occur from events in space, in Antarctic snow, deep-sea sediments, and samples from the moon. As Ofer added, samples from Mars, if tested in the same way as lunar and terrestrial samples, could reveal a similar rise in the iron isotope about 2 to 3 million years ago.

The heliosphere could have been obscured for anywhere from a few hundred years to just a million years, Boston University’s Over said. launch. The moment the Earth and other planets moved away from the cloud, the heliosphere returned.

To examine their findings, the team is now trying to determine the position of the Sun about seven million years ago, where there is evidence of another peak in the proportions of plutonium-244 and iron-60 in Earth’s ice and sediments. They are trying to create a digital twin — essentially, a high-tech model — of the heliosphere in order to better model the types of conditions our solar system might experience. Finally, additional data from ESA’s Gaia mission could further help the team determine the Sun’s precise position at that moment in the ancient past.

According to the Utah Geological Survey, at least Five major ice ages have occurred on Earth. The first occurred more than 2 billion years ago, and the most recent began about 3 million years ago. According to NASA, ice ages could be triggered by a combination of factors, including changes in Earth’s orbit, decreasing amounts of energy from the Sun, the composition of the atmosphere, changes in ocean currents, and even volcanoes, which were responsible for the formation of ice. A year without summer. In other words, we don’t want theories explaining Earth’s various cold moments, and the jury is still out on how Earth’s presence outside the heliosphere might have triggered such an extremely cold period.

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