| This guidance system reads gyroscopes and accelerometers and sends appropriate commands to attitude control thrusters. |
| According to the original scheme, spacewalking astronauts would have replaced failing batteries, gyroscopes and fine-guidance sensors. |
| The four on-board gyroscopes have now experienced and measured relativistic effects for eight months. |
| The gyroscopes sense angular motion by measuring the Coriolis effect induced by rotation, using a vibrating MEMS structure. |
| And they could play a role in hyper-accurate gyroscopes or help etch superfast computer chips. |
| On 8 September the craft suddenly lost its direction control and it was three minutes before the on-board gyroscopes could regain it. |
