Can a Passing Star Save Earth? Scientists Assess Odds Amid the Sun's Fiery Fate

Scientists predict the Sun's increasing heat will make life unsustainable in a billion years. A passing star could potentially rescue Earth by relocating it to a more habitable zone, though the likelihood is slim, according to a study.

Cosmic Odds: 12,000 Simulations Explore Earth's Fate in Close Stellar Encounters

Scientists hailing from the University of Bordeaux, France, and the Planetary Science Institute in Tucson, Arizona, conducted 12,000 simulations to explore the potential consequences of a star passing within 100 astronomical units (approximately 9.3 billion miles) of Earth.

Surprisingly, the simulations revealed that the Solar System exhibited remarkable stability, with 92% of cases resulting in minimal disruption even when a star passed by.

Despite initial expectations, Sean Raymond, a study author from the University of Bordeaux, noted that disturbing planetary orbits is a challenging task for a passing star, requiring significant interference. However, the simulations suggested a slim chance of the passing star redirecting Earth away from potential harm.

In 0.28% of scenarios, the star managed to pull Earth into a more temperate region, either beyond Pluto or into interstellar space, presenting a variety of outcomes.

Raymond highlighted an unconventional silver lining, asserting that it's more challenging to revive a "fried" planet than to warm up a frozen one. He explained that planets with moderately thick hydrogen atmospheres, if free-floating, could retain sufficient heat to sustain liquid water on their surfaces.

The study also explored instances where the star captured Earth during its passage, but the outcomes were not consistently favorable, often resulting in collisions with celestial bodies like the moon or Venus.

The findings estimated a 1% likelihood of a star passing through the Solar System in the next billion years, with a 1 in 350 chance of Earth being propelled into a habitable orbit. Combining these odds, the researchers suggested a 1 in 35,000 chance that a passing star could ultimately rescue Earth's long-term prospects.

The study, titled "Future trajectories of the Solar System: dynamical simulations of stellar encounters within 100 au" published in the peer-reviewed journal Monthly Notices of the Royal Astronomical Society on November 27, shed light on the potential cosmic scenarios that could shape the fate of our planet.

A Glimpse Into the Solar System's Futurey When the Sun Dies

In approximately 4.5 billion years, the Sun will reach the end of its life cycle, marking the beginning of significant changes for the Solar System. The initial challenge arises as the Sun, in its aging process, accumulates helium in its core through ongoing hydrogen fusion.

Over the next few hundred million years, the outer regions of the solar system will experience heightened heat and radiation as the sun transforms into a red giant. This outward expansion will alter the habitable zone, potentially transforming the moons of outer planets and objects in the Kuiper belt, like Pluto.

Ultimately, the Sun will shed its outer layers, leaving behind a white dwarf-a dense core of carbon and oxygen. Initially emitting intense X-ray radiation, the white dwarf will eventually cool down, creating a new habitable zone much closer than Mercury orbits today. However, planets or planetary cores within this zone would be susceptible to tidal disruption due to the white dwarf's gravitational forces.

Despite these challenges, astronomers discovered a gas giant orbiting a white dwarf in October 2021, offering a glimpse into the solar system's potential future. The planet, detected through gravitational microlensing, provides insights into the evolving dynamics as the sun evolves into a white dwarf, offering a unique perspective on distant celestial phenomena.