The continuity of life on Earth depends on the Sun. Scientists have determined that the speed of the Sun is decreasing. What effect can the speed of the sun have on the earth? What causes a decrease in the speed of the sun in terms of its properties?
Is the speed of the sun decreasing?
Our Sun, which formed 4.6 billion years ago, was much more active than today. It hurled large quantities of rays and plasma into space, as do all young stars in general. Thus, it also affected the development of the planets.
At that time, for example, Mars lost most of its atmosphere and water, while our Earth may have survived this phase unscathed thanks to its strong magnetic field.
However, there is one question that awaits an answer.
How fast was the Young Sun spinning?
“We don’t know what our sun looked like in the first billion years, but that’s a very important topic,” says Prabal Saxena of NASA’s Goddard Center for Spaceflies.
Because the rotation speed of a star affects the magnetic field and therefore the strength and frequency of solar storms. During the research of other stars, it was learned that fast-rotating stars are more active than slow rotating ones.
Young stars spin faster than older stars. Because of the lack of clear evidence, astronomers could only guess whether our Sun belonged to fast- or slow-rotating stars. But Saxena and her team have found some kind of time machine from our Sun’s teenage years.
The researchers came to this finding while analyzing a study examining the composition of lunar rock from the Apollo mission. The peculiarity of this rock is that it contains significantly less sodium and potassium than those on our earth. The amount of these volatile elements in the lunar regolith depends not only on the rock type but also on environmental effects.
And these include the erosion-triggering effect of solar storms. Using this information, Saxena and her team designed a model simulation that shows what the strength and frequency of solar storms (in the early Sun) should be for the sodium to potassium ratio to become like this. While designing the model, meteorite impact, volcanic activities, and the effects of the magnetic field were also taken into account.
Here’s the result: If the Sun were a fast-spinning star, its powerful jets would blow out all the sodium and potassium from the Moon. So there must have been severe solar storms at least ten times a day. Then even our Earth’s magnetic field wouldn’t be able to withstand them.
So much so that the air pressure in our world would drop well and our planet could lose its water. But according to Lunar regodlites, our Sun was a slow-spinning and relatively inactive star. Astronomers have calculated that our Sun rotates only once every nine to ten days in its first billion years.
Since then, the rotation speed has slowed even more. Our sun now rotates once every 45 days. But the results cannot be said to be one hundred percent. The results are based on sodium and potassium values in samples brought from the Moon by the Apollo astronauts about fifty years ago.
And these are usually collected near the lunar equator, which is not the oldest region of the Moon’s crust. More precise data will be available with new Moon missions.