It seems to be an early Christmas present for astronomers and scientists alike.

The European Space Agency (ESA) says its spacecraft has snapped what appears to be a large patch of fresh, untrodden snow on Mars.

The Korolev crater is 82 kilometres across and is in the northern lowlands of Mars.

The ESA's Mars Express mission launched on June 2nd 2003, and reached Mars six months later.

The satellite fired its main engine and entered orbit around the Red Planet on December 25th - making this month the 15-year anniversary of its orbit insertion and the beginning of its science programme.

The images were taken by the Mars Express High Resolution Stereo Camera (HRSC).

They show five different 'strips' that have been combined to form a single image, with each strip gathered over a different orbit.

The crater is also shown in perspective, context, and topographic views - all of which offer a more complete view of the terrain in and around the crater.

Plan view of Korolev crater | Image: ESA/DLR/FU Berlin

Korolev crate is an especially well-preserved example of a martian crater and is filled not by snow but ice, with its centre hosting a mound of water ice some 1.8 kilometres thick all year round.

The ESA says this ever-icy presence is due to a phenomenon known as a 'cold trap', which occurs as the name suggests.

The crater's floor is deep, lying some two kilometres vertically beneath its rim.

The very deepest parts of Korolev crater, those containing ice, act as a natural cold trap: the air moving over the deposit of ice cools down and sinks, creating a layer of cold air that sits directly above the ice itself.

This colour-coded topographic view shows the relative heights of the terrain in and around Korolev crater | Image: ESA/DLR/FU Berlin

The crater is named after chief rocket engineer and spacecraft designer Sergei Korolev, dubbed the father of Soviet space technology.

Korolev worked on a number of well-known missions including the Sputnik program and the Vostok and Vokshod programs of human space exploration.

He also worked on a number of rockets that were the precursors to the successful Soyuz launcher.

The region of Mars has also been of interest to other missions, including ESA's ExoMars programme, which aims to see if life ever existed on the planet.