The sun’s corona can reach a steamy 3 million-or-so degrees Celsius, but scientists struggled to explain how until earlier this year: By high-speed Alfven waves roiling in solar magnetic fields.

The Japanese Hinode spacecraft, launched in 2006, snuck another peek at the weird waves. The detailed results confirm previous observations made by the Sacramento Peak Observatory in New Mexico.

The new data—which generated 10 studies(!) in a single issue of the journal Science last week—may also explain what drives the solar wind (and violent outbursts of radiation). A recent Los Angeles Times article offered some perspective on the matter:

A big radiation storm in 1972, during the era of U.S. manned lunar exploration, could have had lethal consequences, said Ron Zwickl, a spokesman for the Space Environment Center in Boulder, Colo. If astronauts had been on the moon at the time, “I doubt that any of them would have lived long,” Zwickl said.

Needless to say, Alfven waves are something NASA will keep in mind as potential manned missions to the moon and Mars enter serious planning.