The Earth's magnetism has probably saved the planet from the Sun's harmful "superflares." The protective magnetic field may have played a major role in the Earth's survival, a new study says.
Researchers from Harvard-Smithsonian Center for Astrophysics (CfA) said that the study of the Sun-like star Kappa Ceti shows that a magnetic field is important for Earth to be conducive to life.
About 4 billion years ago, life existed on Earth. The Sun, however, was violent and released "superflares". Its powerful solar winds could have burned the solar system and anything that thrived on the planets.
Though it somehow became lesser violent today, scientists said that the Earth's magnetic field became the planet's protection against these winds.
"To be habitable, a planet needs warmth, water, and it needs to be sheltered from a young, violent Sun," said Jose-Dias Do Nascimento of CfA.
The young star is located 30 light years away in the constellation Cetus. Though scientists call it young, it is about 400 to 600 million years old.
Kappa Ceti is way younger than the solar system's Sun. Like how the sun acted when it was younger, Ceti is a boisterous mess as it erupts powerful magnetic activity.
It releases about 10 to 100 million times more energy than the most powerful solar flare ever observed from the Sun. Its solar winds are also 50 times more powerful than the Sun's solar wind.
A fierce stellar this strong could rip off any life on a planet, unless it is shielded by a magnetic field. If a planet does not have a magnetic field, its atmosphere could disappear because of strong solar winds. Mars suffered this fate as the solar winds from the then violent Sun caused tremendous damage that it became a cold and dry desert.
In the new study published in the journal The Astrophysical Journal Letters, the scientists made a model showing the effects of Kappa Ceti on Earth. Billions of years ago, the magnetic field of the Earth is estimated to be as strong as it is today. They also measured the frequency of solar wind eruptions Kappa Ceti produces to give them a better understanding on the solar system's Sun and its history.
