Plotting a course through outer space is tricky, but stellar corpses called pulsars are pointing the way to a new form of celestial navigation

Pulsars may point the way Bryan Olson

IT WAS a flying visit all right. NASA’s New Horizons probe took nine and a half years to reach Pluto, and yet it could only observe the dwarf planet for three weeks as it zipped past and out into the farthest reaches of the solar system. The images it has beamed back are nothing short of breathtaking, revealing a complex world of enormous floating ice mountains, smooth plains and reddish patches reminiscent of Mars. But just imagine what we could be learning about Pluto had we been able to hang around a little longer.

A decade ago, when New Horizons launched, we couldn’t plot a course accurately enough to get the craft into Pluto’s orbit. If a little-known mission launching this year goes to plan, however, NASA will showcase a new form of celestial navigation that promises far superior precision. Instead of relying on Earthly clocks as we do now, this system relies on the universe’s most reliable timepieces – rapidly rotating stellar corpses many hundreds of thousands of light years from home.

Harnessing the exquisite regularity of their pulses won’t just help us achieve ever closer encounters of the dwarf planet kind, it would also enable crewed missions to reach Mars without relying on constant contact with Earth. In the long run, it could even help our descendants plot a course in interstellar space.

Currently, spacecraft in low Earth orbit, including the International Space Station (ISS), use the familiar Global Positioning System (GPS) to tell us where they are. This is a network of satellites orbiting our planet at an elevation of …