Mars is known for its polar ice caps, consisting of both water ice and carbon dioxide, which stand out sharply against the surrounding rusty color of the landscape. But plenty of ice can be found outside the main ice caps of Mars, including underground. One image, in particular, shows an excellent example of such a Martian ice landscape – an “ice pond” in a crater near the north pole — very suitable for this time of year in the northern hemispheres of Earth and Mars. Right … it's winter in the northern hemisphere of Mars. The northern martian winter solstice came on October 16, 2018 (here is the seasonal calendar of Mars).
The European Space Agency (ESA) received the image above and several other images on this page through its Mars Express orbiter. The above image shows what at first glance looks like a picturesque view of a pristine stretch of Martian snow, but the bright white element is actually water ice that fills the crater of Mars Queen. The rounded mound of ice is captured in exquisite detail; Note the small patches of ice filling in the crevices on the jagged edge of the crater. ESA posted the image on December 20, 2018.
The Queen's crater is about 51 miles (82 km) across and is located in the northern lowland of Mars, south of Olympia Undey – a vast area filled with dunes, which partially surrounds the north pole. The image shows a stunning oblique view of the crater, consisting of five different "bands", combined to form a larger separate image. Each band was received in a different Mars Express orbit. There are also context and topographic views of the crater.
EarthSky moon calendars are cool! They make great gifts. Order now. Come quickly!
The ice that fills the crater is mostly preserved all year round – the thickness of the central part of the ice is 1.1 miles (1.8 km). The crater acts as a cold trap, where the air is cooled and lowered when it moves through ice deposition, creating a layer of cold air that is directly above the ice itself. This cold layer keeps the ice stable and prevents its evaporation or sublimation. The crater itself is quite deep, its bottom lies at a distance of 1.2 miles (2 km) below the edge of the crater.
The Queen’s Crater has also been recently depicted – in part – by the ESA Space Gas Orbiter (TGO), part of the ExoMars mission. TGO arrived on Mars last spring and is designed to search for Mars’s trace gases — tiny amounts of certain gases such as methane.
Ice is distributed on Mars – both on the surface and in the depths – including both water ice and carbon dioxide ice. NASA's Phoenix descent vehicle in 2008 dug a frozen surface near the north pole and tried some of the water ice directly, just a few inches from the surface. Phoenix also watched snow fall in the atmosphere, although he did not reach the ground. So that is an there is also snow on Mars, but unfortunately it never accumulates to ski or sled. On the other hand, ice-filled craters, such as Korolev, can make some perfect rinks for some future Martian settlers!
The Korolev crater was named after Sergei Korolev, the main rocket-builder and spacecraft designer, who was dubbed the father of Soviet space technology.
Mars Express was launched back in 2003 and entered the Mars orbit on December 25 of the same year – 15 years ago this week!
More information about Mars Express can be found on the mission website.
The bottom line: the “frozen pond” in the Korolev crater is an excellent example of how cold, icy terrain on Mars can resemble similar places on Earth — the winter fairyland of Mars.