NASA Can’t Explain What Made This Strange, Deep Hole on Mars
We’re not saying it’s aliens…
by Mike Mcrae
June 5, 2017
You’d think NASA’s Mars Reconnaissance Orbiter (MRO) has seen everything there is to see on the Martian surface in the 11 years it’s orbited our nearest neighbour, but a snapshot taken over the planet’s South Pole has revealed something we can’t explain.
While the planet’s entire surface is pocked with various depressions and craters, a vast pit spotted among the “Swiss cheese terrain” of melting frozen carbon dioxide appears to be a bit deeper than your average hole, leaving astronomers to try and figure out what made it.
A lot of things can make holes in Mars’ rocky terrain: more than half a million meteorite impacts have left craters; collapsing lava tubes have created deep pits; ancient floods have gouged out giant chasms; and volcanic activity has melted ice to leave funnels.
Occasionally the MRO will come across an odd feature that poses a fun mystery to solve, such as this shallow, circular depression seen earlier this year.
But there’s nothing so shallow about this newly discovered pit. Just take a look at it:
“Swiss cheese”-like terrain and a pit of unknown origins on Mars in an image taken by NASA’s Mars Reconnaissance Orbiter (NASA/JPL-Caltech/University of Arizona)
Being summer for Mars’ South Pole, the Sun is low enough in the sky to accentuate shadows over the landscape, making subtle features pop right out. Yet there a glint of light is still able to reveal ice at the bottom of the hole.
Surrounding the pit are patches frozen carbon dioxide. The circles in the ice is thought to where the dry ice has sublimated into gas in the summer sunshine, leaving what astronomers call “Swiss Cheese terrain“.
The image was taken using the MRO’s High Resolution Imaging Science Experiment, or HiRISE camera, which allows researchers to see objects on Mars that are larger than one metre (about 3 feet) in size from about 200 to 400 kilometres (about 125 to 250 miles) above.
That means the pit isn’t tiny – at 50 centimetres (19.7 inches) per pixel, we’re looking at a feature hundreds of metres across. Take a look on NASA’s website for a hi-res version of the image.
So the question is, did something punch its way through, or is it a collapse of some sort?
Without more information, it’s hard to tell, but no doubt NASA will be discussing all of the possibilities.
The MRO has been in Martian orbit since March, 2006, sending back detailed images of the Red Planet’s surface that reveal a dynamic environment where dust devils roam, sand dunes crawl, and occasional bits of Earthling tech are left to gather dust.
After completing all of its primary goals in the first two years, and two mission extensions, the orbiter is still going strong – we’ll almost certainly be seeing more odd holes like this in the future.
“After 11 and a half years in flight, the spacecraft is healthy and remains fully functional,” said MRO Project Manager Dan Johnston.
“It’s a marvelous vehicle that we expect will service the Mars Exploration Program and Mars science for many more years to come.”
WATCH | Giant Hole on Mars Leaves NASA Scientists Confused
The Mars Reconnaissance Orbiter (MRO) has circled our neighboring planet 50,000 times since its launch 11 years ago. In the process, the spacecraft has delivered some stunning and potentially important revelations: a giant volcano that went extinct at about the same time as the dinosaurs on Earth; what our planet would look like to Martians; and three possible landing sites for the Mars 2020 Rover. In short, MRO has done its job.
And yet, NASA has released yet another compelling image from the orbiting spacecraft. The picture shows a large hole that defies easy explanation.
WATCH | Peeling Back Layers of a Martian Polar Ice Cap (Artist Concept)
This artist’s animation illustrates how NASA’s Mars Reconnaissance Orbiter used radar to map the insides of the north polar ice cap on Mars.
The animation begins by showing the orbiter flying above the Red Planet. It then shows the orbiter shooting out beams of radio waves across a slice of the ice cap. The waves, which belong to the radio portion of the electromagnetic spectrum, penetrate through the ice and bounce back at different times depending on the differing concentrations of sand and dust in the ice.
The result is a glimpse inside the layers that make up the ice cap, as demonstrated by the next part of the movie. The ice cap slices open to reveal what the scientists found. Flashing green lights show some of the actual radar reflections, subsequently seen as dark lines delineating the layers. While the uppermost thin layers were observed before in camera images, the deeper layers have been discovered by the Mars Reconnaissance Orbiter. The movie ends by showing the radar image by itself.
The most data-productive spacecraft yet at Mars swept past its 50,000th orbit this week, continuing to compile the most sharp-eyed global coverage ever accomplished by a camera at the Red Planet. In addition, the spacecraft — NASA’s Mars Reconnaissance Orbiter (MRO) — recently aided preparations for NASA’s next mission to Mars, the InSight lander.