The tremendous opportunity to travel far and wide on Mars has always impressed us

As we remember the rover Opportunity, officially dead this week, one thing keeps me in mind: this machine has traveled thirty kilometers on the surface of another planet. And he did it in short, agonizing jets. Over a distance of 14 years, 28 miles do not really seem like that, but consider the many obstacles Oppy has faced, including a creepy 38-day whirling in a sand dune.

The opportunity traveled exactly 45.06 kilometers (28.06 miles) while passing over the Martian surface. That's more than the distance traveled by the lunar rover Apollo 17 (22.2 miles), the Soviet rover Lunokhod 2 (24 miles), the Curiosity rover (12.3 miles) or Opportunity's partner, the Spirit rover (4.8 miles). Along the way, he took pictures of vast planes, sand dunes and craters – and revealed traces of water on the red planet.

It's not easy to drive a rover on Mars. Engineers can not control it in real time, given the 20-minute communication time between planets. If Oppy started sliding down a cliff, for example, the engineers could not send commands to stop it before it was too late. They must therefore send commands to travel a short distance, take new data, reevaluate, and then send new orders. As described by NASA on an information page, moving Oppy is a tedious process.

The rover and his team also overcame many technical malfunctions related to steering, heaters and on-board memory. Violent dust storms have threatened the rover, covering its solar panels with debris and depriving it of its source of energy.

The best example of the difficulties faced by Oppy was the 38 Martian days he spent stranded in a dune, unable to get the traction needed to get out of the soft sand. After more than 629 feet of carefully planned laps, the team was finally able to pull out the rover and continue on.

Finally, what finally overcame the rover was not a sand dune, but a massive Martian dust storm. Nevertheless, the mission was a resounding success that revolutionized our understanding of Mars. During his long travels, Opportunity has captured a wide variety of strange and wonderful images on the red planet. Below, I've collected some of my favorite postcards from the great Oppy Adventure.