As the Solar System orbits the Milky Way, it comes across various Galactic environments with differing interstellar densities, consisting of hot spaces, supernova blast wave fronts, and cold gas clouds.

The Sun’s passage through a thick area of the interstellar medium might affect the Solar System in a number of methods.

The improvement of the pressure compresses the heliosphere, exposing some parts of the Solar System to the cold and thick interstellar medium.

In addition, the quantity of interstellar dust filled into Earth’s environment would increase, possibly improving the shipment of radioisotopes, such as iron-60, by means of dust grains.

The Radcliffe wave is a narrow sinusoidal gas structure, which consists of numerous recognized star-forming cloud complexes, such as CMa, Orion, Taurus, Perseus, Cepheus, North America Nebula, and Cygnus.

This gas structure, with an approximated mass of 3 million solar masses, appears to coherently oscillate like a taking a trip wave and it is believed to belong to the Milky Way’s spiral structure.

“Imagine it like a ship cruising through differing conditions at sea,” stated Dr. Efrem Maconi, a doctoral trainee at the University of Vienna.

“Our Sun came across an area of greater gas density as it went through the Radcliffe wave in the Orion constellation.”

Utilizing information from ESA’s Gaia objective and spectroscopic observations, Dr. Maconi and his associates identified the Solar System’s passage through the Radcliffe wave in the Orion area.

“This discovery builds on our previous work recognizing the Radcliffe wave,” stated University of Vienna’s Professor João Alves.

“We travelled through the Orion area as popular star clusters like NGC 1977, NGC 1980, and NGC 1981 were forming.”

“This area is quickly noticeable in the winter season sky in the northern hemisphere and summer season in the southern hemisphere.”

“Look for the Orion constellation and the Orion Nebula (Messier 42)– our Solar System originated from that instructions!”

“The increased dust from this Galactic encounter might have had a number of results.”

“It might have permeated the Earth’s environment, possibly leaving traces of radioactive aspects from supernovae in geological records.”

“While present innovation might not be delicate sufficient to find these traces, future detectors might make it possible.”

The research study suggests the Solar System’s passage through the Orion area happened in between roughly 18.2 and 11.5 million years earlier, with the most likely time in between 14.8 and 12.4 million years back.

This timeframe lines up well with the Middle Miocene Climate Transition, a considerable shift from a warm variable environment to a cooler environment, causing the facility of a continental-scale model Antarctic ice sheet setup.

While the research study raises the possibility of a link in between the previous traverse of the Solar System through its Galactic area and Earth’s environment through interstellar dust, the authors highlight that a causal connection needs more examination.

“While the underlying procedures accountable for the Middle Miocene Climate Transition are not completely recognized, the readily available restorations recommend that a long-lasting reduction in the climatic greenhouse gas co2 concentration is the most likely description, although big unpredictabilities exist,” Dr. Maconi stated.

“However, our research study highlights that interstellar dust associated to the crossing of the Radcliffe wave may have affected Earth’s environment and possibly contributed throughout this environment shift.”

“To change the Earth’s environment the quantity of extraterrestrial dust in the world would require to be much larger than what the information up until now recommend.”

“Future research study will check out the significance of this contribution. It’s essential to keep in mind that this previous environment shift and present environment modification are not equivalent because the Middle Miocene Climate Transition unfolded over timescales of a number of hundred thousand years.”

“In contrast, the existing international warming advancement is taking place at an extraordinary rate over years to centuries due to human activity.”

The research study was released in the journal Astronomy & & Astrophysics

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E. Maconi et al2025. The Solar System’s passage through the Radcliffe wave throughout the middle Miocene. A&A 694, A167; doi: 10.1051/ 0004-6361/2024 52061