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Scientists have long wondered how Mars transformed into the cold, dry desert it is today when it once was very similar to Earth. But NASA published new research Thursday from its Mars-orbiting MAVEN spacecraft that might at last solve this scientific mystery.

Mars鈥� atmosphere leaks into space at about a half a pound a second. Although this might sound impressive, scientists say that even this rate over the solar system鈥檚 4.5-billion-year history would not be enough to fully erode a thick Earth-like atmosphere.

According to research published in this week鈥檚 issue of Science, MAVEN鈥檚 data reveals stronger erosion rates of Mars鈥� atmosphere during solar storms. The "interplanetary coronal mass ejection," also called an aurora, causes 鈥渄ramatic spikes in the number of oxygen and carbon dioxide ions spewing into space.鈥澛�

Jasper Halekas, a professor of physics and astronomy at the University of Iowa and a member of the MAVEN team, that the solar storm studied in early March 鈥渋s the equivalent of a tsunami at Mars.鈥�

Because Mars does not have a global magnetic field like Earth, its atmosphere is left unprotected and vulnerable to periodic solar storms from the sun, caused by high-energy blasts of the sun鈥檚 gas and solar ultraviolet radiation.

The storms are so powerful, that Professor Halekas said the energy hitting Mars鈥� atmosphere is comparable to a million tons of TNT an hour, or 鈥渙ne large nuclear weapon per hour, if you like.鈥�

MAVEN scientists say we have Earth鈥檚 magnetic field to thank for our aurora-ignorance.聽

鈥淲hat we in hindsight were pretty foolish about was, what Earth鈥檚 magnetic field really does is prevent auroras from happening everywhere on Earth,鈥� Dr. Nick Schneider, a planetary scientist at the University of Colorado and a member of the MAVEN team told The Times.聽

鈥淲e sort of did this dope slap, saying, 鈥榃ell, of course, what鈥檚 going to prevent these particles from the sun from slamming into Mars鈥� atmosphere anywhere and maybe everywhere?鈥欌�澛�

To better understand when Earth-like conditions were present on the Red Planet, scientists with NASA鈥檚 MAVEN mission want to understand how much of Mars鈥� atmosphere has been lost to space, including influence from such solar storms.聽

鈥淪olar-wind erosion is an important mechanism for atmospheric loss, and was important enough to account for significant change in the Martian climate,鈥� Joe Grebowsky, a MAVEN project scientist explained in . 鈥淢AVEN also is studying other loss processes 鈥� such as loss due to impact of ions or escape of hydrogen atoms 鈥� and these will only increase the importance of atmospheric escape.鈥�

This report contains material from Reuters and The Associated Press.