Once upon a time,"Hou Yi shoots the sunThe legend is widely spread in the land of China, and people only regard it as a popular myth and legend, and no one knows whether this ancient legend is a true interpretation of a multi-star system.
After a long period of follow-up research, scientists have found:Milky WayThere are about them40%-50% of stars are binary or multi-star systems, which are gravitationally bound to each other relative to the host star, revolve around their center of mass.
Not only that, but there are three-star systems, four-star systems, and even multi-star systems with more stars in the universe. In these complex multi-star environments, the existence and stability of planets are fascinating.
In 2011, scientists discovered the first planetary candidate to orbit four stars, Kepler-64, which is located in the direction of the constellation Cygnus in a system consisting of two pairs of binary stars orbiting each other, the so-called ".Conjoined binary star system
This gives scientists reason to believe that the Sun also has a companion star with an extremely long orbital period, taking about 26 million years to complete one revolution?
Why 26 million years？Because there is a hypothesis called ".Extinction cyclesIt was first proposed by paleontologists Daniel O'Connor and Richard Álvarez, among others, who noted that several large-scale extinction events in Earth's history appear to be somewhat cyclical, about 26 million to 30 million years old.
This periodicity is thought to be related to the periodicity of the solar system moving between the spiral arms of the Milky Way, or to be affected by periodic perturbations by other celestial bodies, such as possible solar companions.
Scientists have even chosen a name for this hypothetical companion star, which is called ".Nemesis", which refers to the goddess of revenge in Greek mythology, so it is also calledNemesis
Because it could bring periodic disasters, for example, it is believed that it could affect the orbits of comets in the outer solar system, especially in the Oort cloud belt, and thus crash into the Earth, triggering mass extinction events on Earth.
However, after a long period of searching and research, so far, the scientific community has not found enough evidence to prove the existence of Nemesis star. This concept is more of a theoretical speculation than a conclusion based on observational facts.
But,There are still some scientists who believe that the Sun will most likely have a distant and faint companion star, which remains concerned about its potential threat.
The Atlas (Asteroid Land Impact Final Warning System) project continuously monitors the night sky by setting up multiple telescope stations around the world, looking for fast-moving near-Earth objects, and calculating their orbits to determine whether there is a possibility of a collision with Earth.
By providing sufficient warning time, scientists can better assess the risk of impact, develop evacuation plans, and even attempt deflection operations to avoid impact events if technology allows for future events.
Although the main goal of the Atlas is not to find a solar companion like Nemesis, it does reflect the high level of vigilance of scientists for any celestial object that could threaten Earth's safety
Whether there is a mysterious companion star near the Sun is still a mystery to be solved。Once it is confirmed that Nemesis really exists, its unique orbital period characteristics and the potential harm it may bring will inevitably bring key considerations and new research directions to future space exploration programs and the formulation of Earth defense strategies.