How to Build a Spacecraft to Save the World

How to Build a Spacecraft to Save the World

There are more than a thousand asteroids with diameters larger than Didymos and Dimorphos combined, and if any of those were to strike Earth, it could lead to mass extinction and the collapse of civilization.“Everyone knows it’s possible to hit an asteroid,” says Justin Atchison, a DART mission designer at the Johns Hopkins Applied Physics Laboratory.

How Long Do We Have Before Arctic Ice Melts Away?

How Long Do We Have Before Arctic Ice Melts Away?

These changes are the prelude to summer, when the ice undergoes another radical change: It begins to melt .The icebreaker Polarstern the morning after a crack cleaved the ice floe in two, sending some experiments into the water.

Recovery: Darters and Values

Recovery: Darters and Values

In 1973, 18 weeks before President Nixon signed the Endangered Species Act (ESA), University of Tennessee ichthyologist Dr. David Etnier discovered a new darter in the Little Tennessee River, site of TVA’s Tellico Dam, already under construction.