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If you had been in northern Canada 45 million years ago, you might have encountered the distant ancestor of all of the oaks in the Americas. That single species gave rise to 220 more and two distinct lineages—red oaks and white oaks—that moved south through the boreal zone to populate large swaths of the continent all the way into Mexico. These two findings—simultaneous evolutionary diversification in the red and white oaks, each following the same geographic routes; and two relatively recent origins of the Mexican oaks—are a surprise conclusion to a scientific mystery that went unresolved until now. Research published this week in the journal New Phytologist tells this story of the evolutionary history of American oaks for the first time.

NASA and NOAA satellites have provided data on Maria as it strengthened into a major Hurricane headed toward the Leeward Islands. NASA's Aqua satellite provided an infrared look at Maria that showed cooling cloud top temperatures and NOAA's GOES satellite provided an animation of imagery that showed the storm developing and strengthening. The GPM satellite found "Hot" towering clouds that indicated strengthening was occurring before Maria became a major hurricane.

They produce winds strong enough to swallow whole islands in their maw. They whip up waves that re-shape cityscapes. And they bring rains and floods, devastating and seemingly relentless.

The hurricane trifecta of Harvey, Irma and Jose have dominated headlines weeks. Irma alone has set a series of records.

Visible imagery from NASA's Aqua satellite showed Tropical Depression Lee as a weak swirl of clouds around its center with most of its clouds and thunderstorms pushed east of its center.

What scientists thought caused certain classes of northern lights is not what causes certain classes of northern lights.

In a landmark study that has toppled what scientists know about the night sky, UAlberta physicists Robert Rankin and Dmytro Sydorenko found that the ionospheric feedback instability (IFI)—the mechanism thought to be the cause of certain types of northern lights—not only doesn’t cause northern lights, it may not even exist at all.