-- Mars used to have cyclical climate changes
 

LOS ANGELES, Dec. 4 (Xinhua) -- Mars used to have cyclical climate changes, likely driven by small variations in the planet's orbit, similar to the way orbital changes cause certain shifts in the Earth's climate, a new study shows.
The tilt of Mars' axis changes by tens of degrees over a 100 customize jordans,000-year period, resulting in a more dramatic variation, said the study.
As the tilt of the Earth's axis varies between 22.1 and 24.5 degrees over a 41,000-year period -- tilting the poles closer or farther away from the sun -- the poles experience varying amounts of glaciation, according to the study.
"This study gives us a hint of how the ancient climate of Mars operated, and shows a much more predictable and regular environment than you would guess from other geological features that indicate catastrophic floods uggs kids outlet, volcanic eruptions and impact events lv on sale," said Caltech graduate student Kevin Lewis, a leading researcher on the project.
NASA's Mars Reconnaissance Orbiter photographed rock outcroppings that revealed a record of cyclical climate fluctuations within many stony layers on the planet, researchers at the California Institute of Technology (Caltech) said Thursday.
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