NASA launches $1-bn laser-shooting mission to track ice melt
NASA on Saturday launched its most advanced space laser, ICESat-2, a $1-billion mission that will shoot lasers towards Earth to track the planet's melting ice. The preceding mission, ICESat, which lasted from 2003-2009 revealed that ice cover was disappearing from Greenland and Antarctica. The new laser will fire 10,000 times per second, whereas ICESat fired 40 times a second.