Earth's Orbit Altered by Close Encounter with a Passing Star, Scientists Discover
Researchers have determined that a passing star could have altered Earth's orbit three million years ago, potentially influencing the planet's development in a lasting manner.
This groundbreaking revelation was published in The Astrophysical Journal Letters.
According to the study, the star known as HD-7977 might have significantly changed the orbit of our planet around the Sun. This event is thought to have had a long-standing impact on Earth's evolutionary course.
Approximately 2.8 million years ago, HD-7977 is believed to have flown close by our Solar System. Scientists estimate the star approached the Sun to possibly within 31,000 astronomical units (AU). However, some projections suggest the encounter may have been as close as 4,000 AU.
While such proximity might seem improbable at first glance, close encounters of this nature are not uncommon. Researchers estimate that about every million years, another star passes within 50,000 AU of the Sun; even closer encounters within a distance of 10,000 AU occur approximately every ten million years.
Orbit simulations indicate that HD-7977 came sufficiently near to exert an influence on Earth's trajectory.
The plausibility of such an event is underscored by the understanding that the colossal gravitational forces exerted by the gas giants within our Solar System, such as Jupiter and Saturn, already affect Earth's orbit. Even minute changes in the paths of these giant planets can lead to alterations in Earth's orbital pattern.
Therefore, the passing star merely needed to cause disturbances in the orbits of these two giant planets, which in turn, would resonate down to Earth.
The orbit alterations prompted by the star's close passage are also suspected to have resulted in drastic climate changes on Earth. One notable illustration is the Paleocene-Eocene Thermal Maximum event that took place 56 million years ago, during which the planet's average temperature rose by 5-8 degrees Celsius.
According to the study, the star known as HD-7977 might have significantly changed the orbit of our planet around the Sun. This event is thought to have had a long-standing impact on Earth's evolutionary course.
Approximately 2.8 million years ago, HD-7977 is believed to have flown close by our Solar System. Scientists estimate the star approached the Sun to possibly within 31,000 astronomical units (AU). However, some projections suggest the encounter may have been as close as 4,000 AU.
While such proximity might seem improbable at first glance, close encounters of this nature are not uncommon. Researchers estimate that about every million years, another star passes within 50,000 AU of the Sun; even closer encounters within a distance of 10,000 AU occur approximately every ten million years.
Orbit simulations indicate that HD-7977 came sufficiently near to exert an influence on Earth's trajectory.
The plausibility of such an event is underscored by the understanding that the colossal gravitational forces exerted by the gas giants within our Solar System, such as Jupiter and Saturn, already affect Earth's orbit. Even minute changes in the paths of these giant planets can lead to alterations in Earth's orbital pattern.
Therefore, the passing star merely needed to cause disturbances in the orbits of these two giant planets, which in turn, would resonate down to Earth.
The orbit alterations prompted by the star's close passage are also suspected to have resulted in drastic climate changes on Earth. One notable illustration is the Paleocene-Eocene Thermal Maximum event that took place 56 million years ago, during which the planet's average temperature rose by 5-8 degrees Celsius.
