Robotic space link to be launched

After a series of delays, Nasa has scheduled April 15 as the launch date for the first robotic spacecraft designed to rendezvous in orbit with other satellites without any human intervention.

If all goes as planned, the Dart spacecraft - short for Demonstration of Autonomous Rendezvous Technology - will catch up with an orbiting Pentagon satellite and manoeuvre around it, making close approaches and moving away.

The US space programme has so far relied on astronauts to manoeuvre around spacecraft in orbit and repair them.