Desert planets are rocky
worlds that are very dry.
They can be cold, like Mars,
or very hot, like Venus.
They could be hospitable to life.


for image ideas

Arrakis. Dune. Desert planet.” You may have heard this line in the movie Dune, but desert worlds are more than science fiction. In fact, they could be very common among terrestrial exoplanets.  

These arid worlds are very, very dry. They are either completely devoid of water or, similar to the deserts here on Earth, there may be tiny amounts of moisture lurking below ground. Desert planets are likely to have rocky and sandy surfaces, resembling the windswept dunes of the Sahara or the rugged expanse of the Atacama high desert.

There are actually desert planets in our own solar system: Mars and Venus can be considered desert planets because their surface lacks any liquid water. Like Mars, desert planets can have thin, tenuous atmospheres and be rather frigid, because any surface heat slowly evaporates into space. Mars may actually have water ice tucked away below ground. The European Space Agency suggests that there are huge reservoirs of water ice just a few feet below ground in Mars’ “Grand Canyon,” the Valles Marineris region.

A Venus-like desert planet would look very different. Venus has a thick (and stinky) greenhouse atmosphere which is dense with sulphuric acid. The atmosphere traps heat, so on the surface, it’s a steamy 475°C, hot enough to melt lead. While this doesn’t sound very hospitable to life, some water steam may be trapped in the higher – and cooler – regions of the atmosphere, and there’s an ongoing discussion about whether some form of life could be floating through the clouds of Venus’ atmosphere.

At the moment, desert exoplanets are theoretical, scientists have not confirmed a desert world beyond our solar system with any certainty. Still, models suggest that they may be incredibly common, and science fiction worlds could actually turn out to be real places, whether here in our Solar System or in a galaxy far, far away.

Mars as an Exoplanet

Mars is a desert planet, so it makes an excellent model for desert planets outside our Solar System. Scientists are testing different options, like changing the type of star Mars may orbit, and tinkering with its atmosphere.
Find out more about “exoplanet” Mars

Could Arrakis be Real?

Science fiction could become science fact according to a team of researchers who took Frank Herbert’s desert planet Arrakis as a model to test whether any life could survive there. Spoiler alert: it totally could!
Find out more about the “real” Arrakis

Tatooine Exists!

Scientists have named the planet Kepler 16b “Tatooine,” because it orbits two suns, just as George Lucas imagined. In fact, Star Wars planets like Jakku and Jedha may actually exist and are likely more habitable than Mars.
Find out about Star Wars desert planets



Could life exist on such an arid world? Actually, desert planets are more likely to harbour life than Earth-type planets or ocean worlds because they are more stable. Water can easily freeze over or boil into space – but rock and sand are resistant to such heat changes. Also, consider that life can be found in Earth’s deserts, either hiding below ground or through adaptations that allow them to survive. Some organisms store moisture in their tissue, while others shield themselves against the harsh environment by growing tough hides. Some plants simply wait for the right time: their seeds linger for years on the dry ground and then spring to life after a long-awaited rain shower.
If life does exist on a desert world, it would more likely be found on the planet’s poles than in its equatorial regions because moisture tends to linger in the polar regions.


May patterns in the sand indicate life? Could they even be a means of communication?

There is a phenomenon called “singing sand,” which is sand that produces sound when it is windy, or when you walk across it. Find out more here: https://en.wikipedia.org/wiki/Singing_sand

What if a source of water was found deep underground? How would a lifeform get to it?

How would lifeforms guard and maximize the availability of scarce water?

Could life rely on something else than water? 

Dust devils are a common phenomenon on desert worlds. On Mars, they are pretty huge! Here’s one captured by the Curiosity rover: https://www.youtube.com/watch?v=k8lfJ0c7WQ8