NASA’s Mars-orbiting Maven spacecraft has discovered that the sun likely robbed the red planet of its once-thick atmosphere and water.
On Thursday, scientists reported that even today, the solar wind is stripping away about 100 grams of atmospheric gas every second. That’s about a quarter-pound a second lost to the stream of charged particles shooting away from the sun at 1 million mph (1.61 million kph).
Big solar storms traveling at twice that speed increase the escape rate by 10 to 20 times – and more. Because of their prevalence billions of years ago, these storms would have been enough to gut the atmosphere of ancient Mars and transform it from a moist, warm place potentially capable of microscopic life to the cold, dry desert of today.
“I can’t help but imagine hamburgers flying out of the Martian atmosphere, one per second,” Maven scientist Dave Brain told reporters with a smile. “It’s instead oxygen and carbon dioxide that are leaving the planet, which are important both for water and for the climate of the planet overall.”