Let's talk about our Sun, the so-called yellow dwarf. It supports life on Earth, determines the climate. However, it also threatens humanity with inevitable death. "What are yellow dwarfs?" - will ask an inquisitive, but not too advanced in astronomy reader. A yellow dwarf is a type of star with a mass of 0.8 to 1.2 times the mass of the Sun and a surface temperature of 5000-6000 ° K. A yellow dwarf lives for an average of 10 billion years, and then grows in size and becomes a red giant. The latter, in turn, sheds the outer layers of gas, and its core turns into a white dwarf.
Optimistic forecast
"Excuse me, what will happen to the Earth in this case?" - the same inquisitive reader will be alarmed. Astrophysicists Robert Smith from the University of Sussex (UK) and Klaus Peter Schroeder from the University of Guanajuato (Mexico) are confident that our planet will first heat up and then fall into the Sun, in the fiery depths of which it will disappear. And this will happen, by cosmic standards, soon - in just a little over seven billion years, So is it really all a foregone conclusion, and mankind awaits a gloomy prospect of death in the heat of the sun? It turns out that there is also an optimistic scenario. Our Sun, at the stage of transformation into a red giant, will quickly lose part of its mass. As a result, its gravitational attraction will sharply decrease. Therefore, the orbits of all the planets of the solar system will increase, and they will be at a considerable distance from the star.
Delay of billions of years
However, an article by Smith and Schroeder, published in the British magazine Monthly Notices of the Royal Astronomical Society, gives a disappointing estimate. Scientists claim that during the red giant stage, the Sun will slow down its rotation speed around its axis. As a result, the reverse gravitational influence of the Earth on the star will increase. As a result, Smith and Schroeder argue, “there will be an effect on the surface of a star similar to the tides of our seas and oceans, influenced by the gravity of the sun and the gravity of the moon. As a result of this effect, on the side of the Sun closest to our planet, a huge tidal hump will appear - a bulge that will quickly bulge towards the Earth. This hump will slow down the rate of expansion of the earth's orbit. And that will be more meaningfulthan the opposing positive effect of a simultaneous loss of solar mass. It turns out that the Earth's orbit, after increasing, will begin to decrease, and the planet will still fall on the Sun. The only consolation is that it will happen in more than seven billion years. But it turns out that even such a delay does not suit everyone.
Promotional video:
Ferries are better
Don Korikanski, Greg Laughlin and Fred Adams - scientists from the University of Santa Cruz (California) - have come up with a clever option to save the planet.
Moreover, this option, in the opinion of most of the scientific community, would be more appropriate in a science fiction novel than on the pages of a scientific journal. Scientists propose to slightly correct the trajectory of the Earth with the help of … some large asteroid periodically passing near the planet. You just need to lasso it and launch it along the desired trajectory. This will allow not only to avoid the fall of the Earth on the Sun, but also to maintain the climatic conditions familiar to people. It is proposed to make such an adjustment once every six thousand years.
Smith and Schroeder believe that “this option looks quite feasible both technologically and energetically. Of course, now our technological capabilities are very far from the level that will ensure the successful implementation of the project, but there is no need for great haste in this matter."
However, should astrophysicists make a mistake in their calculations, and the asteroid will crash into the Earth much earlier than it hits the Sun. Astrophysicists consider the creation of "rescue ferries" that will tow the Earth away from the Sun as a more acceptable solution.
Elena Gatchina