NASA’s Curiosity rover recently shared a picture of a ‘doorway’ on Mars, and as is usually the case with these things, many people are wondering how the strange object came to be. Although it’s a minuscule speck compared to the entirety of the universe, our Solar System is home to all kinds of mysteries. Jupiter has a giant storm that’s been raging on for hundreds of years. Saturn’s intricate ring system is unlike any of its neighboring planets. Uranus is the only planet in the Solar System to spin on its side.

And, of course, there’s Mars. While it may not have record-breaking storms or a giant ring system, Mars stands out for its own reasons. It’s one of the closest planets to Earth, was once home to ancient lakes, and has recorded evidence of carbon on the planet — one of the key building blocks for life. Scientists have yet to confirm if life ever did (or still does) exist on Mars, but it’s something humans are repeatedly trying to find out.


Related: Mars Worms? New Rover Photo Reveals Tiny, Peculiar Rock Formation

One of the main ways we’ve tried hunting for Martian life is with rovers like Curiosity and Perseverance. These rovers patrol the Red Planet, analyze its surface, and capture seemingly endless photos of their journies. That last point has proven to be one of the most buzzworthy aspects of the rovers. As you might expect, sharing thousands upon thousands of photos of an alien world often turns up peculiar results. NASA’s rovers have spotted rock formations that look like spaceships, worms, and even giant frogs. Most recently, the internet is raving over a new Curiosity photo that appears to reveal an alien ‘doorway’ on Mars.

The Truth Behind This Martian ‘Doorway’

Mars by NASA.

At first glance, the object above really does look like a doorway. It’s nestled into a large rock formation and appears to have a deep entrance. There’s also what looks like a small rock awning over the entrance of the doorway. While the whole thing looks like something Mars aliens may have constructed millions of years ago, the reality of the ‘doorway’ isn’t nearly as exciting.

Like we’ve seen with photos of Mars ‘worms’ and ‘frogs,’ the doorway you see here isn’t actually a doorway at all. Instead, it’s just a natural formation carved into part of Mars’ rocky surface. Speaking to Live Science, geologist Neil Hodgson theorizes that the Mars doorway is the result of erosion on the Red Planet. Hodgson believes that the rock making up the outer part of the doorway is strata — ‘harder sandy beds’ that may have formed in an ancient river. As the strata’s been exposed to the constant wind on Mars’ surface for billions of years, it’s gradually morphed into a ‘doorway.’ Gizmodo also spoke with Ashwin Vasavada from the Mars Science Laboratory, who said that the doorway is “just the space between two fractures in a rock.”

Even if the Mars doorway may not be some ancient alien structure, it’s still a stunning example of Mars’ geology. A planet that primarily consists of rocks and sand doesn’t sound exciting on the surface, but as we’ve seen time and time again, Mars is home to some truly incredible visuals. Whether it be a worm, doorway, or whatever else NASA finds next, Mars is nothing if not entertaining.