Brown scientist answers how Peruvian meteorite made it to Earth

Planetary geologists had thought that stony meteorites would be destroyed when they passed through Earth's atmosphere. This one struck ground near Carancas, Peru, at about 15,000 miles per hour. Brown... Click here for more information.

PROVIDENCE, R.I. [Brown University] — It made news around the world: On Sept. 15, 2007, an object hurtled through the sky and crashed into the Peruvian countryside. Scientists dispatched to the site near the village of Carancas found a gaping hole in the ground.

Peter Schultz, professor of geological sciences at Brown University and an expert in extraterrestrial impacts, went to Peru to learn more. For the first time, he will present findings from his travels at the 39th annual Lunar and Planetary Science Conference in League City, Texas, in a talk scheduled for 2 p.m. on March 11, 2008. Brown graduate student Robert “Scott” Harris collaborated on the research, joined by Jose Ishitsuka, a Peruvian astrophysicist, and Gonzalo Tancredi, an astronomer from Uruguay.

What Schultz and his team found is surprising. The object that slammed into a dry riverbed in Peru was a meteorite, and it left a 49-foot-wide crater. Soil ejected from the point of impact was found nearly four football fields away. When Schultz’s team analyzed the soil where the fireball hit, he found “planar deformation features,” or fractured lines in sand grains found in the ground. Along with evidence of debris strewn over a wide area, the shattered sand grains told Schultz that the meteorite had maintained a high rate of speed as it shot through the atmosphere. Scientists think it was traveling at roughly 15,000 miles per hour at the moment of impact.

“Normally with a small object like this, the atmosphere slows it down, and it becomes the equivalent of a bowling ball dropping into the ground,” Schultz said. “It would make a hole in the ground, like a pit, but not a crater. But this meteorite kept on going at a speed about 40 to 50 times faster than it should have been going.”