You've heard of panspermia, the idea that life exists throughout space and was carried to Earth by comets? What if the reverse occurred, with microbes on Earth ejected into space by asteroid impacts, escaping into the solar system billions of years ago?
Scientists recently studied the formation of the huge crystals inside the giant geode of Pulpí, located deep in a Spanish mine. They revealed the natural process that grew the crystals, ripening them over thousands of years and making them literally crystal clear.
As temperatures drop, broad-leafed deciduous trees – think maples and oaks – withdraw the green chlorophyll from their leaves. Their leaves turn colors and fall. Evergreens solve the problem of winter in a different way.
What kicked off a rapid cooling on Earth 12,800 years ago? Some geologists believe a fragmented comet or asteroid collided with Earth and caused the change. Read more from a scientist whose fieldwork at a South Carolina lake adds to the growing pile of evidence.
The European Space Agency was asking this question late last week, as multiple fires burned across the globe. Read more about 2019 fires, and fire-tracking via satellite, here.