Has there ever been life on Mars? Scientists do not agree. Some say: Sure, why not? Others say: No Way! Fact is, there are good reasons to believe that indeed, life may have once formed on our red neighbour planet.

If life once existed on Mars, it probably means that there was once liquid water as well, because all known life forms life need water (and a few other things, of course).

Thousands of images from Mars – made by US and European satellite missions – give even more reason to believe that water once existed on its surface. The images show traces of rivers, lakes and even oceans. Or, at least, that's what it looks like.

Erin Kraal, now at Virginia Tech, USA.

By comparing her results with what we know about Mars she has learned more about what exactly happened on this planet long time ago. Erin can now tell, for instance, that water had flown for only a short interval of time (a few thousands of years) in certain places on Mars. This makes a difference, because if Mars had been wet for a long time, life might have formed on this fascinating planet.

In the animation below you will see Erin with Dutch highschool student Quirine in the Utrecht lab. Quirine pours red dye in the miniriver, showing how an alluvial fan works (explained in the next article and film).

This is how a fan works. Erin and Quirine put some drops of red dye in the river, showing how the water spreads out by branching channels at the fan surface. Eurotank at Utrecht University. Click the image to start the slide show.

Finally, start your own experiments and discover new things about the Red Planet! We will tell you exactly how to do them.

Read Erin's article Water on Mars?