This spectacular 'blue marble' image is the most detailed true-color image of the entire Earth to date, using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer of Earth. Reuters/NASA

Scientists are worried that in about 500 million years, life on Earth may be severely endangered due to sun’s expansion. Conditions on Earth would become so harsh that it would be impossible for life to sustain. That is why researchers from Columbia University have suggested various incredible measures to combat doomsday, such as uploading human minds to machines or altering Earth’s orbit by launching an asteroid.

Astrophysicists Daniel Wolf Savin and Michael Hahn from Columbia University have explained to science magazine Nautilus how life on Earth would slowly decline. They are of the opinion that if the Earth is at all able to survive apocalyptic events, such as getting hit by an extinction-sized asteroid or nuclear apocalypse, humans will have less than 500 million years to live on this planet. This is well before the sun swells to become a red giant and melt the earth in 6 billion years.

The scientists suggest physically moving the Earth’s orbit by launching a 100km-wide asteroid “on an elliptical orbit that passed close to the Earth every 5,000 years.” This may slowly nudge the Earth’s orbit further away from the sun gravitationally. However, great care must be taken so that the asteroid does not hit Earth. They even suggested building a huge solar sail, 20 times or more the diameter of the Earth that would drag our planet away from the sun. This would be possible as there would be interaction with sun’s photons, very similar to how a kite flies in wind. Due to gravity, the Earth would remain tied to the solar sail.

Another method to secure humans from doomsday would be uploading themselves into machines. Although that is something unimaginable in the present day, deeper understanding of neuroscience and advanced computing resources of future may make it possible.

However, all these measures may work till the sun does not become a red giant. Life on earth will die much before the sun turns in a red giant due to decrease in natural levels carbon dioxide. Gradually all plant life will be wiped out, which in turn would mean the end for humans. Earth’s temperature will rise dramatically, and in roughly 1.5 billion years, the poles would even be too hot to host non-microbial life.