On Christmas Day 2003, the European Space Agency (ESA) spacecraft called Mars Express settled into an orbit around the red planet and began training its instruments towards the surface. More than 15 years and 5,000 orbits later, its mission to provide new insights into Earth's most intriguing neighbor has surpassed all expectations.

"It was our first mission to Mars. We actually planned for a two-year lifetime at the planet with a possible extension of another two years; and now here we are at 10 years and counting," Alvaro Gimenez, ESA's science director, told the BBC in 2013. "It's been a great success from an engineering point of view, but also from a science perspective because of the extraordinary global view it has given us of Mars."

Perspective view looking into a 20 km-wide crater in the Thaumasia mountain range. The crater interior shows slumping of its crater walls, but a flat, smooth floor, relating to glacial processes.
Perspective view looking into a 20 km-wide crater in the Thaumasia mountain range. The crater interior shows slumping of its crater walls, but a flat, smooth floor, relating to glacial processes. (Photo: ESA)

In addition to discoveries about Mars' upper atmosphere and ionosphere, Mars Express has also provided breakthroughs in our understanding of the red planet's once-wet past. In 2005, the spacecraft detected the presence of hydrated minerals, indicating that large amounts of liquid water once had a prolonged existence on the planet's surface.

Of course, some of the biggest highlights have been visual, with the spacecraft's High Resolution Stereo Camera capable of capturing extremely-detailed images of the planet's surface. By 2015, more than 97 percent of Mars had been photographed by Mars Express at a resolution of 60 meters (196 feet) per pixel.

In celebration of 15 years of exploration with the Mars Express, the ESA released a montage of both flat and 3D images chronicling some of the spacecraft's most stunning captures. If you can get past the terrible soundtrack, there's likely something in the video below that will make your jaw drop.

The Mars Express is presently funded to continue its mission exploring the red planet through at least the end of 2020.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.