The Perils of Pluto

A seemingly simple trip to the world at the edge of the solar system is looking more like a voyage into the perfect meteor storm.



Try this for a challenge. Your task is to thread a needle—but not your average sewing-kit variety. The needle in question is five miles away. No matter how fast you push the thread, it will take 9.5 years to get it there. 

When your thread finally dangles in front of the needle’s eye, perfectly aligned, don’t get cocky, because a dust speck blowing by could fray your thread, ruining all that you’ve done. And did I mention that if you fail, you will have blown $700 million?

Now you have a sense of the slow-motion cliffhanger that is New Horizons, a NASA space probe currently racing toward Pluto and its large moon Charon at 35,000 miles per hour. “We have to hit our arrival time window within 450 seconds,” says principal investigator Alan Stern, a former chief of NASA’s science mission directorate who currently hangs his hat at Southwest Research Institute in Boulder, Colorado. 

“In terms of distance, Pluto and Charon are orbiting 20,000 kilometers [12,000 miles] apart and we need to hit our aim point within 1 percent of that. And if we hit anything even the size of a rice grain, it could kill us.”

One might expect these to be restful times for the New Horizons team. Their spacecraft blasted off on January 19, 2006, and will not reach Pluto until July 2015. Right now, New Horizons cruises smoothly through interplanetary space. But nothing about Pluto is simple or predictable.