What will happen when the sun starts to die? And how can we keep humanity safe?

Earth
Image by PIRO4D from Pixabay

Like all of the stars in the universe, our Sun has an expiry date. Our solar system is completely dependent on the sun as its central force and source of heat. When the sun progresses in its star cycle, it has the potential to boil our Earth, making it completely inhospitable.

So what will happen when the sun starts to die? And how can we keep The Earth – and humanity – safe?

5 billion years from now, it is predicted that the Sun will expand, embarking on the next stage in the life cycle of a star, becoming a Red Giant. It is possible that the Earth could be in the path of the Sun’s transformation. If humanity still exists after those 5 billion years, would we leave the Earth? OR could we attempt to even move it?

The beginning of the slow death of the sun – the Red Giant – involves the star swelling into a larger, more red, and fiery ball of gas, wiping out anything that may be nearby. Including the Earth.

For survival, the human race would have to take action long before this happens. If we were to evacuate 7.5 billion people on the planet, it would potentially take a billion space shuttles. If 1,000 shuttles were launched every day, it would still take over 2,700 years to complete. Following this, millions of years could be spent traveling to a hospitable planet and terraforming it.

moving the whole planet

Would we save ourselves this trouble by moving the whole planet instead?

This idea is a theoretically possible solution. We would only need to give the Earth a boost into a different orbit and keep it on course.

Every time a rocket is launched into space, the planet’s orbit is slightly shifted. This effect is so subtle, is not felt by people on Earth. To use a method like this to move the Earth out of danger, we would have to increase its velocity by 1,200 meters (3,937 feet) per second, requiring 7,000 of the most powerful rockets being built.

One of the major problems with this idea is the distance the Earth would need to travel. To be safe, we would have to move into an orbit similar to that of Mars. Moving something as large as the Earth that far could take 1+ billion years. We would also potentially use up to one-third of the Earth’s resources and mass as a propellant. This is evidently not very efficient. To move the Earth more efficiently without the major loss of resources, other alternative methods of propulsion would have to be used. To use the same resources as our current rockets would be extremely harmful. One possibility is the use of electric propulsion. Unlike the current chemicals used in space travel, electric propulsion doesn’t require large masses of resources. Compared to sacrificing one-third of the Earth’s resources and mass, this method would only sacrifice 2% every 1 billion years.