Worried about man-made climate change?
...menacing space rocks sometimes come in twos.
Researchers have outlined some of the best evidence yet for a double space impact, where an asteroid and its moon apparently struck Earth in tandem.
Using tiny, plankton-like fossils, they established that neighbouring craters in Sweden are the same age - 458 million years old.
Details of the work were presented at the 45th Lunar and Planetary Science Conference in The Woodlands, Texas, and the findings are to be published in the Meteoritics and Planetary Science journal.It's just a matter of time.