Solar Slaughter
Even if the Earth dodges Mercury, the blue planet eventually will be turned into an oven by the sun, says NASA planetologist Chris McKay.
As the sun burns, the hydrogen in its core converts to helium by fusion, a process through which the nuclei of atoms meld together. Fusion produces a tremendous amount of heat. So as time passes, the 5 billion-year-old star gets hotter and brighter.
In about 1 billion years, scientists predict the sun will shine about 10 percent brighter than it does now. The extra energy will heat Earth to well over 200 F. The oceans will boil off, the climate will collapse and “any kind of real estate won’t be worth anything anymore,” said astrophysicist Klaus-Peter Schrœder of the University of Guanajuato in Mexico.
“We’ll have to look for a new planet."
Those who don’t want to leave home will have to hope that Schrœder’s colleague, astronomer Robert Smith of the University of Sussex, is right. Smith suggests scientists may be able to enlarge Earth’s orbit by manipulating asteroids visiting our solar system.
Shifting the path of these rocky passers-by so that they move in front of Earth should create a slight pull on the planet and help to speed it up. Earth’s quicker pace would make its orbit slightly larger. If done enough times over millions of years, Earth’s orbit could swell by about 5 percent, which would translate into about 10 percent less solar energy reaching our planet, Schrœder said.
That may only buy the planet time, however. In about 7 billion years, Schrœder says, the sun will bloat into a red giant, a much brighter and voluminous version of its current self.
“It will be so big that the Earth will be inside the sun,” McKay said.
In the meantime, unless Smith’s orbital expansion works out, Earth will almost certainly cook and steam under the sun’s powerful rays.
“Not that I’m a great believer, but credit needs to be given sometimes,” Schrœder quipped. “The Bible’s predictions that we’ll end up in an eternal fire are somewhat accurate.”
Image courtesy of American Museum of Natural History's space show "Journey to the Stars"