The cold trap does not allow to thaw.
The European Space Agency (ESA), in honor of the 15th anniversary of the Mars Express automatic station, published pictures of the Korolev crater, taken in April.
The camera (High Resolution Stereo Camera) captured a crater in five passes from the side of the device. Then the agency’s experts collected a complete image from the images. The diameter of the crater is 82 kilometers.
The ESA stressed that the crater is in a “cold trap”: it is filled with ice about 1.8 kilometers thick–and it does not melt all year round. The object is located next to the dune field of Olympia Undea, which surrounds the northern polar cap of Mars.
The crater was discovered in 1973 and named in honor of Sergei Korolev, the founder of the Soviet cosmonautics.