The wide strip of land in Utopia Planitia imaged by Mars Express. The dark volcanic material is on the right, while grabens can be seen on the left. (Image credit: ESA/DLR/FU Berlin) Europe's Mars orbiter has captured high-resolution images of an ancient sea bed on the Red Planet, revealing that Mars' appearance can change over a matter of decades. The High Resolution Stereo Camera on the veteran Mars Express mission, which launched all the way back in 2003, recently captured new views of Utopia Planitia, which is a vast northern lowland plain spanning 2,100 miles (3,300 kilometers). Utopia Planitia is thought to be the bruise left by the impact of a small dwarf planet between 4.1 and 4.3 billion years ago. After China's Zhurong rover landed in 2021, it found evidence for coastal sediments in an ancient shoreline , implying that long ago Utopia Planitia was filled with enough water to form a gigantic sea that also extended into the neighboring basin, Vastitas Borealis.…