Distribution of once-watery basins on Mars
![](https://cdn.sci.esa.int/documents/33745/35367/1567213746979-Distribution_of_once-watery_basins_on_Mars_625.jpg)
Date: 27 February 2019
Satellite: Mars Express
Copyright: Topography: NASA/MGS/MOLA; Crater distribution: F. Salese et al. (2019)
This image shows the distribution of a number of deep craters (marked as dots) recently explored as part of a study into groundwater on Mars.
The background image is shown in colours representing topography: reds and oranges are lower elevations, and blues and greens are higher ones.
The study found that the floors of the basins, which sit over 4000 m deep, show signs of past water – the first geological evidence that the Red Planet once had a system of interconnected groundwater-fed lakes that spanned the entire planet.
Last Update: 1 September 2019