The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.
Find out more about space activities in our 23 Member States, and understand how ESA works together with their national agencies, institutions and organisations.
Exploring our Solar System and unlocking the secrets of the Universe
Go to topicProtecting life and infrastructure on Earth and in orbit
Go to topicUsing space to benefit citizens and meet future challenges on Earth
Go to topicMaking space accessible and developing the technologies for the future
Go to topicThank you for liking
You have already liked this page, you can only like it once!
ESA’s Mars Express radar team recently made an exciting announcement: data from their instrument points to a pond of liquid water buried about 1.5 km below the icy south polar ice of Mars.
Between 2012 and 2015 Mars Express made repeated passes over the 200 km wide study region in Planum Australe, bouncing radio waves through the planet’s surface and recording the properties of the reflected signal with its Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, MARSIS.
The radar ‘footprints’ on the surface are represented in the image and are colour-coded corresponding to the ‘power’ of the signal reflected from features below the surface. The brightest reflections are coloured in blue, with data from multiple overlapping orbits defining a 20 km-wide zone corresponding to the triangular shaped patch to the right of centre in this image.
Directly below this patch, under repeating layers of ice and dust at a depth of 1.5 km, is a base layer that has radar properties corresponding to liquid water. Despite the below-freezing temperatures on Mars, it can be kept liquid by the presence of salts, and it may be heavily laden with water-saturated sediments.
Water once flowed freely on the Red Planet’s surface, but it is not stable today. Discovering liquid water buried underground is essential for understanding the evolution of Mars, the history of water on our neighbour planet, and its habitability.