Contrary to what many scientists have made believe, planets don’t need large moons for a stable tilt and climate.
Previously, the researchers have showed that without the moon, Jupiter's gravity would make the current tilt of some 23 degrees stroll in pandemonium between 0 and 85 degrees, which would result in huge climate swings, making it hard for life to survive, especially large, land-based organisms like us.
But now, a study has revealed that moonless planets have been discarded unjustly.
“There could be a lot more habitable worlds out there,” the New Scientist quoted Jack Lissauer of NASA’s Ames Research Center in Moffett Field, California, who led the research, as saying.
“The astrobiology community has taken it to mean there will be these really wild variations, and we wanted to test that.”
For the study, Lissauer and his colleagues replicated a moonless Earth over 4 billion years, about the age of the Earth today.
The researchers found that Earth’s tilt varied only between 10 and 50 degrees, a much smaller range than inferred by previous studies.
There were also long stretches of up to 500 million years when the tilt was predominantly stable, varying between 17 and 32 degrees.
Although scientists have accepted that much larger changes might still take place on timescales longer than 4 billion years but in that situation, the changes will not hold any relevance anyway as sun-like stars burn out after 10 billion years.