View from Mars Express on Ismenia Patera
The images from Mars Express show the crater of Ismenia Patera, located on the Red Planet. However, its origin still seems mysterious: a trace from the fall of a meteorite or the remnant of a super volcano?
Ismenia Patera is a kind of “patera”, which is translated from Latin as “flat bowl”. Located in the region of Arabia - the transition zone between the northern and southern part of Mars. The topography of the Red Planet is clearly divided into two parts: the northern lowlands and the southern elevations. It is this gap that causes the greatest interest among scientists. It is believed that a split could appear due to a single or several blows, or it is a question of ancient plate tectonics, whose origin remains hazy.
Ismenia Patera stretches for about 75 km. The center is surrounded by a ring of hills, blocks and pieces of rock that could have been thrown out as a result of the blows. Also, discarded material created small failures and depressions. The bottom is covered with ice deposits showing signs of movement.
Ismenia Patera in Arabia
The images were acquired on January 1 using a high-resolution stereo camera on the Mars Express (it has been rotating around Mars since 2003). Such clear images allow better study of various Martian features, such as the formation of "scratches" on the surface. But how did Ismenia Patera come about? There are two main theories. The first indicates the fall of the meteorite. Then precipitation with ice and sediment occurred, which filled the crater until it collapsed, creating cracks and an uneven landscape.
The second says that it is not a crater at all, but a place of a volcano. In the past, a major eruption occurred, which not only released a lot of magma, but also led to the destruction of the volcano itself.
The photo shows a perspective view of Ismenia Patera in the Arabia Land area. Image received on January 1, 2018 on the Mars-Express camera. It is worth noting uneven terrain around and inside the crater
Such powerful volcanoes are called super-volcanoes. Researchers still cannot say for sure whether they exist on the Red Planet. The land of Arabia also shows signs of the location of an ancient and long-inactive volcanic province. In fact, there is another candidate for super volcanoes - Siloe Patera.
Features of volcanic origin, such as an irregular shape, low topographic relief, relatively raised rims and an obvious lack of discarded material. Some of these signs are also present in crater formations. More details can be found with further observations.