Firing on all engines, Nasa's latest rover to Mars has executed a course adjustment that put it on track for a landing in August.
Deep space antennas monitored the one-ton rover nicknamed Curiosity as it fired its thrusters in a choreographed three-hour manoeuvre.
"We've completed a big step toward our encounter with Mars," Brian Portock of the Nasa Jet Propulsion Laboratory said in a statement.
The course correction is the most important task Curiosity will perform during its 352-million-mile trip to the red planet, but it is not unprecedented.
Previous robotic explorers have had to adjust their paths several times en route to landing.
As Nasa celebrated Curiosity's latest milestone, Russia's space agency grappled with its doomed Phobos-Ground probe.
Bound for a Martian moon, Phobos-Ground became stranded in Earth orbit soon after launching in November. After several failed attempts to put it back on course, pieces of the probe could plunge through Earth's atmosphere as early as this weekend.
Meanwhile, Curiosity had racked up 80 million miles and was travelling at 10,200 mph relative to the Earth.
The action began when engineers uploaded commands to Curiosity's on-board computers. Though it performed the move without human interference a day later, engineers were on standby in the off chance of a need to abort.
The team will spend the next week testing the spacecraft's communication system and other components. A second smaller path adjustment was planned for March.