Did comets bring life to Earth? New Cambridge study weighs in

When comets hit Earth billions of years ago, they pelted the planet too fast and too steep for them to have delivered fragile organic molecules, according to a new study. Using advances in computer simulations, a University of Cambridge-led team of researchers ran scenarios of comet strikes, comet interactions with an atmosphere, and gravity's influence on comet movements through space to determine whether they could have brought the chemical ingredients for life to Earth. Rather than look at a bunch of important molecules, the researchers focused on one in particular: hydrogen cyanide, or HCN. Made of one hydrogen, one carbon, and one nitrogen atom, it's a simple molecule commonly carried on comets.